AGILE Astronomical Telegrams

ATel #1160| Atel #1167| ATel #1199| ATel #1221| ATel #1278| ATel #1300| ATel #1308| ATel #1320| ATel #1394
ATel #1428| ATel #1436| ATel #1445| ATel #1492| ATel #1495| ATel #1545| ATel #1547| ATel #1574| ATel #1581
ATel #1582| ATel #1583| ATel #1585| ATel #1592| ATel #1619| ATel #1634| ATel #1641| ATel #1705| ATel #1713
ATel #1732| ATel #1775| ATel #1782| ATel #1827| ATel #1830| ATel #1848| ATel #1917| ATel #1957| ATel #1968
ATel #1976| ATel #2017| ATel #2019| ATel #2047| Atel #2238| ATel #2242| ATel #2310| ATel #2322| ATel #2326
ATel #2344| ATel #2348| ATel #2361| ATel #2376| ATel #2382| ATel #2385| ATel #2403| ATel #2416| ATel #2454
ATel #2461| ATel #2467| ATel #2484| ATel #2512| ATel #2551| ATel #2552| ATel #2609| ATel #2641| ATel #2645
ATel #2686| ATel #2698| ATel #2715| ATel #2724| ATel #2761| ATel #2772| ATel #2855| ATel #2866| ATel #2880
ATel #2882| ATel #2903| ATel #2950| ATel #2971| ATel #2994| ATel #2995| ATel #3008| ATel #3034| ATel #3043
ATel #3049| ATel #3058| ATel #3059| ATel #3141| ATel #3151| ATel #3199| ATel #3239| ATel #3282| ATel #3286
ATel #3357| ATel #3386| ATel #3387| ATel #3448| ATel #3470| ATel #3544| ATel #3658| ATel #3858| ATel #3862
ATel #3907| ATel #3910| ATel #3934| ATel #3939| ATel #4153| ATel #4154| ATel #4389| ATel #4842| ATel #4856
ATel #4867| ATel #5234| ATel #5422| ATel #5506| ATel #5682| ATel #6182| ATel #6217| ATel #6231| ATel #6234

 

Increasing gamma-ray activity of the Blazar 3C 454.3 detected by AGILE

ATel #6234; A. Bulgarelli (INAF/IASF-Bo), M. Tavani (INAF/IAPS, and Univ. Roma Tor Vergata), V. Fioretti, F. Gianotti, M. Trifoglio (INAF/IASF-Bo), F. Verrecchia, F. Lucarelli, C. Pittori (ASDC and INAF/OAR), S. Vercellone (INAF/IASF-Pa), G. Piano (INAF/IAPS), I. Donnarumma (INAF/IAPS), E. Striani (CIFS and INAF/IAPS), M. Cardillo (INAF/OA-Arcetri and INAF/IAPS), A. Giuliani, S. Mereghetti, P. Caraveo, F. Perotti (INAF/IASF-Mi), A. Chen (Wits University and INAF/IASF-Mi), S. Colafrancesco (INAF/OAR and Wits University), E. Del Monte, Y. Evangelista, M. Feroci, F. Lazzarotto, L. Pacciani, P. Soffitta, E. Costa, I. Lapshov, M. Rapisarda, A. Argan, G. Pucella, S. Sabatini, A. Trois, V. Vittorini (INAF/IAPS), F. Fuschino, M. Galli, C. Labanti, M. Marisaldi, G. Di Cocco (INAF/IASF-Bo), A. Pellizzoni (INAF/OA-Cagliari), M. Pilia (ASTRON, the Netherlands), G. Barbiellini, E. Vallazza (INFN Trieste), F. Longo (Univ. Trieste and INFN Trieste), A. Morselli, P. Picozza (INFN and Univ. Roma Tor Vergata), M. Prest (Univ. dell'Insubria), P. Lipari, D. Zanello (INFN and Univ. Roma Sapienza), P. W. Cattaneo, A. Rappoldi (INFN Pavia), P. Giommi (ASDC), L. Salotti, and G. Valentini (ASI).
on 14 Jun 2014; 17:24 UT
Credential Certification: Andrea Bulgarelli (bulgarelli@iasfbo.inaf.it)

Subjects: Gamma Ray, AGN, Blazar, Transient

Referred to by ATel #: 6236 The AGILE satellite detects a strong enhancement in gamma-ray activity from the FSRQ 3C 454.3 since the recent AGILE ATels #6182 and #6217, the NIR flare (ATel #6213) and the optical variability observed by MIRO (Atel #6232). A maximum likelihood analysis of the AGILE-GRID data for the integration period between 2014-06-12 20:34:44 UT and 2014-06-14 01:16:29 UT, gives a flux F=(8.6 +/- 1.8)x 10^-6 ph/cm^-2/s^-1 (E > 100 MeV) at 9 sigma significance level. This measurement was obtained with AGILE observing a large portion of the sky in spinning mode. Multifrequency observations of the source are strongly encouraged.

 

AGILE detection of a gamma-ray flare from the PSR B1259-63 region

ATel #6231; C. Pittori, F. Verrecchia (ASDC and INAF/OAR), M. Tavani (INAF/IAPS, and Univ. Roma Tor Vergata), V. Fioretti (INAF/IASF-Bo), G. Piano (INAF/IAPS), F. Lucarelli (ASDC and INAF/OAR), E. Striani (CIFS and INAF/IAPS), S. Vercellone (INAF/IASF-Pa), A. Bulgarelli (INAF/IASF-Bo), I. Donnarumma (INAF/IAPS), M. Cardillo (INAF/OA-Arcetri and INAF/IAPS), F. Gianotti, M. Trifoglio (INAF/IASF-Bo), A. Giuliani, S. Mereghetti, P. Caraveo, F. Perotti (INAF/IASF-Mi), A. Chen (Wits University and INAF/IASF-Mi), S. Colafrancesco (INAF/OAR and Wits University), E. Del Monte, Y. Evangelista, M. Feroci, F. Lazzarotto, L. Pacciani, P. Soffitta, E. Costa, I. Lapshov, M. Rapisarda, A. Argan, G. Pucella, S. Sabatini, A. Trois, V. Vittorini (INAF/IAPS), F. Fuschino, M. Galli, C. Labanti, M. Marisaldi, G. Di Cocco (INAF/IASF-Bo), A. Pellizzoni (INAF/OA-Cagliari), M. Pilia (ASTRON, the Netherlands), G. Barbiellini, E. Vallazza (INFN Trieste), F. Longo (Univ. Trieste and INFN Trieste), A. Morselli, P. Picozza (INFN and Univ. Roma Tor Vergata), M. Prest (Univ. dell'Insubria), P. Lipari, D. Zanello (INFN and Univ. Roma Sapienza), P. W. Cattaneo, A. Rappoldi (INFN Pavia), P. Giommi (ASDC), L. Salotti, and G. Valentini (ASI).
on 13 Jun 2014; 21:59 UT
Credential Certification: Francesco Verrecchia (francesco.verrecchia@asdc.asi.it)

Subjects: Gamma Ray, >GeV, Binary, Neutron Star, Transient, Pulsar

Recently, the post-periastron phase of the pulsar binary system PSR B1259-63 has attracted considerable attention (Atels #6204, #6216 and #6225). AGILE is now detecting transient gamma-ray emission above 100 MeV from a source positionally consistent with the binary pulsar PSR B1259-63. Integrating from 2014-06-11 04:00 UT to 2014-06-13 10:30 UT, a preliminary maximum likelihood analysis yields a detection positioned in the 100 MeV < E < 200 MeV band at Galactic coordinates (l,b) = (305.11,-0.95) +/- 0.9 (stat.) +/- 0.2 (syst.) (RA=197.79, Dec=-63.74 J2000). The gamma-ray flux is F =(4.4 +/-1.5) x 10E-6 ph/cm2/sec for photon energies higher than 100 MeV. This measurement was obtained with AGILE observing a large portion of the sky in spinning mode. Multifrequency observations of the source are strongly encouraged.

 

Renewed gamma-ray activity of the Blazar 3C 454.3 detected by AGILE

ATel #6217; F. Verrecchia (ASDC and INAF/OAR), V. Fioretti (INAF/IASF-Bo), F. Lucarelli, C. Pittori (ASDC and INAF/OAR), A. Bulgarelli (INAF/IASF-Bo), M. Tavani (INAF/IAPS, and Univ. Roma Tor Vergata), S. Vercellone (INAF/IASF-Pa), G. Piano (INAF/IAPS), I. Donnarumma (INAF/IAPS), E. Striani (CIFS and INAF/IAPS), M. Cardillo (INAF/OA-Arcetri and INAF/IAPS), F. Gianotti, M. Trifoglio (INAF/IASF-Bo), A. Giuliani, S. Mereghetti, P. Caraveo, F. Perotti (INAF/IASF-Mi), A. Chen (Wits University and INAF/IASF-Mi), S. Colafrancesco (INAF/OAR and Wits University), E. Del Monte, Y. Evangelista, M. Feroci, F. Lazzarotto, L. Pacciani, P. Soffitta, E. Costa, I. Lapshov, M. Rapisarda, A. Argan, G. Pucella, S. Sabatini, A. Trois, V. Vittorini (INAF/IAPS), F. Fuschino, M. Galli, C. Labanti, M. Marisaldi, G. Di Cocco (INAF/IASF-Bo), A. Pellizzoni (INAF/OA-Cagliari), M. Pilia (ASTRON, the Netherlands), G. Barbiellini, E. Vallazza (INFN Trieste), F. Longo (Univ. Trieste and INFN Trieste), A. Morselli, P. Picozza (INFN and Univ. Roma Tor Vergata), M. Prest (Univ. dell'Insubria), P. Lipari, D. Zanello (INFN and Univ. Roma Sapienza), P. W. Cattaneo, A. Rappoldi (INFN Pavia), P. Giommi (ASDC), L. Salotti, and G. Valentini (ASI).
on 9 Jun 2014; 16:08 UT
Credential Certification: Francesco Verrecchia (francesco.verrecchia@asdc.asi.it)

Subjects: Gamma Ray, >GeV, AGN, Blazar, Transient

The AGILE satellite detects a significant enhancement in gamma-ray activity from the FSRQ 3C 454.3 (known as 1AGLR J2254+1609 and 2FGL J2253.9+1609) since the recent AGILE ATel #6182, and the following NIR flare reported by Carrasco et al. (ATel #6213). A maximum likelihood analysis of the AGILE-GRID data for the integration period between 2014-06-07 00:00 UT and 2014-06-09 03:00 UT, gives a flux F=(6.2 +/- 1.2)x 10^-6 ph/cm^-2/s^-1 (E > 100 MeV). This measurement was obtained with AGILE observing a large portion of the sky in spinning mode. Multifrequency observations of the source are strongly encouraged.

 

AGILE detects enhanced gamma-ray activity of the Blazar 3C 454.3

ATel #6182; F. Verrecchia, F. Lucarelli, C. Pittori (ASDC and INAF/OAR), V. Fioretti (INAF/IASF-Bo), M. Tavani (INAF/IAPS, and Univ. Roma Tor Vergata), S. Vercellone (INAF/IASF-Pa), I. Donnarumma (INAF/IAPS), A. Bulgarelli (INAF/IASF-Bo), G. Piano (INAF/IAPS), E. Striani (CIFS and INAF/IAPS), M. Cardillo (INAF/OA-Arcetri and INAF/IAPS), F. Gianotti, M. Trifoglio (INAF/IASF-Bo), A. Giuliani, S. Mereghetti, P. Caraveo, F. Perotti (INAF/IASF-Mi), A. Chen (Wits University and INAF/IASF-Mi), S. Colafrancesco (INAF/OAR and Wits University), E. Del Monte, Y. Evangelista, M. Feroci, F. Lazzarotto, L. Pacciani, P. Soffitta, E. Costa, I. Lapshov, M. Rapisarda, A. Argan, G. Pucella, S. Sabatini, A. Trois, V. Vittorini (INAF/IAPS), F. Fuschino, M. Galli, C. Labanti, M. Marisaldi, G. Di Cocco (INAF/IASF-Bo), A. Pellizzoni (INAF/OA-Cagliari), M. Pilia (ASTRON, the Netherlands), G. Barbiellini, E. Vallazza (INFN Trieste), F. Longo (Univ. Trieste and INFN Trieste), A. Morselli, P. Picozza (INFN and Univ. Roma Tor Vergata), M. Prest (Univ. dell'Insubria), P. Lipari, D. Zanello (INFN and Univ. Roma Sapienza), P. W. Cattaneo, A. Rappoldi (INFN Pavia), P. Giommi (ASDC), L. Salotti, and G. Valentini (ASI).
on 28 May 2014; 14:51 UT
Credential Certification: Francesco Verrecchia (francesco.verrecchia@asdc.asi.it)

Subjects: Gamma Ray, >GeV, AGN, Blazar, Transient

The AGILE satellite detects gamma-ray activity from the FSRQ 3C 454.3 after an extended period of low flux levels during 2013. The source entered the AGILE Field of View at the end of April, 2014, and an enhanced variable emission above 100 MeV has been detected since May 18th. A maximum likelihood analysis of the AGILE-GRID data for the integration period between 2014-05-25 03:00 UT and 2014-05-27 03:00 UT, gives a flux F=(2.4 +/- 0.8)x 10^-6 ph/cm^-2/s^-1 (E > 100 MeV). This measurement was obtained with AGILE observing a large portion of the sky in spinning mode. Multifrequency observations of the source are strongly encouraged.

 

Confirmation by AGILE of increased gamma-ray emission from the blazar 3C 279

ATel #5682; E. Striani, M. Tavani (INAF/IAPS and Univ. Tor Vergata), C. Pittori, F. Verrecchia, F. Lucarelli (ASDC and INAF/OAR), S. Colafrancesco (INAF/OAR and Wits University, Johannesburg), S. Vercellone (INAF/IASF-Pa), A. Bulgarelli, F. Gianotti, M. Trifoglio, V. Fioretti (INAF/IASF-Bo), M. Cardillo, G. Piano, I. Donnarumma, E. Del Monte, Y. Evangelista, M. Feroci, F. Lazzarotto, L. Pacciani, P. Soffitta, E. Costa, I. Lapshov, M. Rapisarda, A. Argan, G. Pucella, S. Sabatini, V. Vittorini (INAF/IAPS), A. Chen, A. Giuliani, S. Mereghetti, P. Caraveo, F. Perotti (INAF/IASF-Mi), F. Fuschino, M. Galli, C. Labanti, M. Marisaldi, G. Di Cocco (INAF/IASF-Bo), A. Pellizzoni, A. Trois (INAF/OA-Cagliari), M. Pilia (ASTRON, the Netherlands), G. Barbiellini, E. Vallazza (INFN Trieste), F. Longo (Univ. Trieste and INFN Trieste), A. Morselli, P. Picozza (INFN and Univ. Roma Tor Vergata), M. Prest (Univ. dell'Insubria), P. Lipari, D. Zanello (INFN and Univ. Roma Sapienza), P. W. Cattaneo, A. Rappoldi (INFN Pavia), A. Antonelli (INAF/OAR and ASDC), P. Giommi (ASDC), L. Salotti and G. Valentini (ASI).
on 22 Dec 2013; 14:10 UT
Credential Certification: Edoardo Striani (edoardo.striani@iasf-roma.inaf.it)

Subjects: Gamma Ray, >GeV, TeV, VHE, AGN, Blazar

AGILE confirms the detection of an enhanced gamma-ray emission from the FSRQ 3C 279 reported by the Fermi-LAT in ATel #5680. A preliminary analysis of the gamma-ray emission detected from 2013-12-19 T06:00 to 2013-12-21 T06:00 (E > 100 MeV) yields a flux F = (600 +/- 170)x10^-8 ph cm^-2 s^-1, in agreement with the flux reported by Fermi-LAT. AGILE analysis reveals that on December 22, 2013 the increased gamma-ray activity from 3C 279 is still ongoing. This measurement was obtained with AGILE observing a large portion of the sky in spinning mode. Multifrequency observations of the 3C 279 are strongly encouraged.

 

After a gamma-ray flare, AGILE detects the Crab Nebula returning to the normal flux level

ATel #5506; F. Verrecchia, C. Pittori, F. Lucarelli (ASDC and INAF/OAR), G. Piano (INAF/IAPS), S. Vercellone (INAF/IASF-Pa), A. Bulgarelli, F. Gianotti, M. Trifoglio, V. Fioretti (INAF/IASF-Bo), M. Tavani, M. Cardillo, E. Striani (INAF/IAPS and Univ. Roma Tor Vergata), I. Donnarumma, E. Del Monte, Y. Evangelista, M. Feroci, F. Lazzarotto, L. Pacciani, P. Soffitta, E. Costa, I. Lapshov, M. Rapisarda, A. Argan, G. Pucella, S. Sabatini, V. Vittorini (INAF/IAPS), A. Chen, A. Giuliani, S. Mereghetti, P. Caraveo, F. Perotti (INAF/IASF-Mi), F. Fuschino, M. Galli, C. Labanti, M. Marisaldi, G. Di Cocco (INAF/IASF-Bo), A. Pellizzoni, A. Trois (INAF/OA-Cagliari), M. Pilia (ASTRON, the Netherlands), G. Barbiellini, F. Longo (Univ Trieste & INFN Trieste), E. Vallazza (INFN Trieste), A. Morselli, P. Picozza (INFN and Univ. Roma Tor Vergata), M. Prest (Univ. dell'Insubria), P. Lipari, D. Zanello (INFN and Univ. Roma Sapienza), P. W. Cattaneo, A. Rappoldi (INFN Pavia), S. Colafrancesco (INAF-OAR and University of the Witwatersrand, Johannesburg), A. Antonelli (INAF/OAR and ASDC), P. Giommi (ASDC), L. Salotti and G. Valentini (ASI)
on 24 Oct 2013; 17:11 UT
Credential Certification: Francesco Verrecchia (francesco.verrecchia@asdc.asi.it)

Subjects: Gamma Ray, >GeV, Neutron Star, Transient, Pulsar

Despite substantial telemetry gaps due to technical problems of the ASI Malindi ground station, AGILE confirms the enhanced gamma-ray emission (E >100 MeV) from the Crab Nebula region during the period October 17-18, 2013 (Fermi LAT ATel #5485), and reports a return to standard flux values on October 20th. Enhanced gamma-ray emission from the source was detected by AGILE on October 18th, with a (E >100 MeV) flux F = (6.8+/-2.2) x 10^-6 ph cm^-2 s^-1 for a significance of about 5 sigma. Since October 20th, AGILE detects a return to standard flux levels, with flux F = (2.9+/-1.3) x 10^-6 ph cm^-2 s^-1 for a 2-days integration (19-21 October, 2013). The recent enhancement and the current flux returned at normal levels show a period of increased gamma-ray emission lasting only a few days. This measurement was obtained with AGILE observing a large portion of the sky in spinning mode.

 

AGILE detection of increasing gamma-ray emission from the blazar PKS 1510-089 following an optical/near-infrared flare

ATel #5422; V. Fioretti (INAF/IASF-Bo), F. Verrecchia, C. Pittori, F. Lucarelli (ASDC and INAF/OAR), S. Vercellone (INAF/IASF-Pa), A. Bulgarelli, F. Gianotti, M. Trifoglio (INAF/IASF-Bo), M. Tavani, M. Cardillo, E. Striani (INAF/IAPS and Univ. Roma Tor Vergata), G. Piano, I. Donnarumma, E. Del Monte, Y. Evangelista, M. Feroci, F. Lazzarotto, L. Pacciani, P. Soffitta, E. Costa, I. Lapshov, M. Rapisarda, A. Argan, G. Pucella, S. Sabatini, V. Vittorini (INAF/IAPS), A. Chen, A. Giuliani, S. Mereghetti, P. Caraveo, F. Perotti (INAF/IASF-Mi), F. Fuschino, M. Galli, C. Labanti, M. Marisaldi, G. Di Cocco (INAF/IASF-Bo), A. Pellizzoni, A. Trois (INAF/OA-Cagliari), M. Pilia (ASTRON, the Netherlands), G. Barbiellini, E. Vallazza (INFN Trieste), F. Longo (Univ. Trieste and INFN Trieste), A. Morselli, P. Picozza (INFN and Univ. Roma Tor Vergata), M. Prest (Univ. dell'Insubria), P. Lipari, D. Zanello (INFN and Univ. Roma Sapienza), P. W. Cattaneo, A. Rappoldi (INFN Pavia), S. Colafrancesco (INAF/OAR and Wits University, Johannesburg), A. Antonelli (INAF/OAR and ASDC), P. Giommi (ASDC), L. Salotti and G. Valentini (ASI)
on 26 Sep 2013; 18:21 UT
Credential Certification: Francesco Verrecchia (francesco.verrecchia@asdc.asi.it)

Subjects: Gamma Ray, >GeV, Request for Observations, AGN, Blazar, Transient

We report the AGILE detection of increasing gamma-ray emission (E > 100 MeV) from a source positionally consistent with the blazar PKS 1510-089 peaking during the period 22-24 September 2013 (following an optical/near-infrared flare of the source recently reported in Atel #5416, M. Buxton et al.). Integrating from 2013-09-22 12:00 UT to 2013-09-24 12:00 UT, a maximum likelihood analysis yields a detection at a significance level above 5 sigma with a source flux F = (4.1 +/- 1.4) x 10e-6 ph/cm^2/s (E > 100 MeV). After September 24th, the source drifted outside the AGILE field of view. During the period preceding the flare, from 2013-08-25 12:00 UT to 2013-09-10 12:00 UT, the source was not detected in gamma-rays above 100 MeV with a flux upper limit of about 2.0 x 10e-6 ph/cm^2/s. Integrating from 2013-09-10 12:00 UT to 2013-09-20 12:00 UT we obtained a detection above 4 sigma with a flux F = (1.2 +/- 0.4) x 10e-6 ph/cm^2/s. This measurement was obtained with AGILE observing a large portion of the sky in spinning mode. Multifrequency follow-up observations of the blazar PKS 1510-089 are strongly encouraged.

 

AGILE confirmation of the increasing gamma-ray activity from 4C +38.41 (BZQ J1635+3808)

ATel #5234; F. Lucarelli (ASDC and INAF/OAR), V. Fioretti (INAF/IASF-Bo), C. Pittori, F. Verrecchia (ASDC and INAF/OAR), M. Tavani, M. Cardillo, E. Striani (INAF/IAPS and Univ. Roma Tor Vergata), A. Bulgarelli, F. Gianotti, M. Trifoglio (INAF/IASF-Bo), S. Vercellone (INAF/IASF-Pa), G. Piano, I. Donnarumma, E. Del Monte, Y. Evangelista, M. Feroci, F. Lazzarotto, L. Pacciani, P. Soffitta, E. Costa, I. Lapshov, M. Rapisarda, A. Argan, G. Pucella, S. Sabatini, V. Vittorini (INAF/IAPS), A. Chen, A. Giuliani, S. Mereghetti, P. Caraveo, F. Perotti (INAF/IASF-Mi), F. Fuschino, M. Galli, C. Labanti, M. Marisaldi, G. Di Cocco (INAF/IASF-Bo), A. Pellizzoni, A. Trois (INAF/OA-Cagliari), M. Pilia (ASTRON, the Netherlands), G. Barbiellini, F. Longo, E. Vallazza (INFN Trieste), A. Morselli, P. Picozza (INFN and Univ. Roma Tor Vergata), M. Prest (Univ. dell'Insubria), P. Lipari, D. Zanello (INFN and Univ. Roma Sapienza), P. W. Cattaneo, A. Rappoldi (INFN Pavia), S. Colafrancesco (INAF-OAR and University of the Witwatersrand, Johannesburg), A. Antonelli (INAF/OAR and ASDC), P. Giommi (ASDC), L. Salotti and G. Valentini (ASI)
on 29 Jul 2013; 21:05 UT
Credential Certification: Fabrizio Lucarelli (fabrizio.lucarelli@asdc.asi.it)

Subjects: Gamma Ray, >GeV, AGN, Blazar, Quasar, Transient

AGILE confirms the increasing gamma-ray activity from the FSRQ object 4C +38.41 (also known as BZQ J1635+3808 (Massaro et al., 2011, A&A 495)) as reported by Fermi-LAT in ATel #5232. Integrating from 2013-07-25 06:00 UT to 2013-07-27 15:00 UT, a Maximum Likelihood (ML) analysis yields a detection at a significance level of about 6 sigma and a flux F(E>100 MeV) = (5.1 +/- 1.7) x 10E-6 ph/cm2/s (quoted error is statistical; in the current AGILE operational mode, the flux determination may be affected by a systematic error) at Galactic coordinates (l,b)=(60.88, 42.75) +/- 0.7 deg (95% stat.) +/- 0.1 deg (syst.) (R.A., Dec.= 248.28, 38.01 deg, J2000) . The peak of the AGILE excess is found at around 0.4 deg from the radio position of 4C +38.41 as reported in Johnston, K. J., et al. 1995 (AJ, 110, 880). On the next 48 hour intervals, 26-28 and 27-29 July 2013, the ML analysis shows a decrease of the activity, with the gamma-ray flux lowering down 2.0 x 10E-06 ph/cm2/s. This measurement was obtained with AGILE observing a large portion of the sky in spinning mode, with telemetry gaps due to intermittent data acquisition at the ground station. Multifrequency observations of the 4C +38.41 are strongly encouraged.

 

Sustained high-flux emission above 100 MeV from the Crab Nebula source

ATel #4867; F. Verrecchia (ASDC and INAF/OAR), E. Striani, M. Tavani (INAF/IAPS, and Univ. Roma Tor Vergata), C. Pittori (ASDC and INAF/OAR), S. Vercellone (INAF/IASF-Pa), A. Bulgarelli, F. Gianotti, M. Trifoglio, V. Fioretti (INAF/IASF-Bo), M. Cardillo (INAF/IAPS and Univ. Roma Tor Vergata), F. Lucarelli (ASDC and INAF/OAR), G. Piano, I. Donnarumma, E. Del Monte, Y. Evangelista, M. Feroci, F. Lazzarotto, L. Pacciani, P. Soffitta, E. Costa, I. Lapshov, M. Rapisarda, A. Argan, G. Pucella, S. Sabatini, V. Vittorini (INAF/IAPS), A. Chen, A. Giuliani, S. Mereghetti, P. Caraveo, F. Perotti (INAF/IASF-Mi), F. Fuschino, M. Galli, C. Labanti, M. Marisaldi, G. Di Cocco (INAF/IASF-Bo), A. Pellizzoni, A. Trois (INAF/OA-Cagliari), M. Pilia (ASTRON, the Netherlands), F. Longo (INFN and Univ. Trieste), G. Barbiellini, E. Vallazza (INFN Trieste), A. Morselli, P. Picozza, (INFN and Univ. Roma Tor Vergata), M. Prest (Univ. dell'Insubria), P. Lipari, D. Zanello (INFN and Univ. Roma Sapienza), P. W. Cattaneo, A. Rappoldi (INFN Pavia), S. Colafrancesco (INAF-OAR and University of the Witwatersrand, Johannesburg), A. Antonelli (INAF/OAR and ASDC), P. Giommi (ASDC), L. Salotti, and G. Valentini (ASI)
on 6 Mar 2013; 23:53 UT
Credential Certification: Edoardo Striani (edoardo.striani@iasf-roma.inaf.it)

Subjects: Gamma Ray, Request for Observations, Neutron Star, Transient, Pulsar

AGILE is detecting sustained gamma-ray emission from the source positionally coincident with the Crab Nebula. Integrating from 2013-03-05 13:00 UT until 2013-03-06 13:00 UT, the AGILE/GRID detects a gamma-ray flux F = (1.1 +/- 0.2) x 10^-5 ph cm^-2 s^-1 above 100 MeV for a significance above 9 sigma. The source continues to be in a high-flux gamma-ray state above 100 MeV following the initial detections reported by Fermi-LAT (ATel #4855) and AGILE (ATel #4856). Multifrequency observations of the Crab covering this episode of sustained gamma-ray emission are strongly encouraged.

 

Enhanced gamma-ray emission from the Crab Nebula region detected by AGILE

ATel #4856; E. Striani, M. Tavani (INAF/IAPS, and Univ. Roma Tor Vergata), F. Verrecchia, C. Pittori (ASDC and INAF/OAR), S. Vercellone (INAF/IASF-Pa), A. Bulgarelli, F. Gianotti, M. Trifoglio, V. Fioretti (INAF/IASF-Bo), M. Cardillo (INAF/IAPS and Univ. Roma Tor Vergata), F. Lucarelli (ASDC and INAF/OAR), G. Piano, I. Donnarumma, E. Del Monte, Y. Evangelista, M. Feroci, F. Lazzarotto, L. Pacciani, P. Soffitta, E. Costa, I. Lapshov, M. Rapisarda, A. Argan, G. Pucella, S. Sabatini, V. Vittorini (INAF/IAPS), A. Chen, A. Giuliani, S. Mereghetti, P. Caraveo, F. Perotti (INAF/IASF-Mi), F. Fuschino, M. Galli, C. Labanti, M. Marisaldi, G. Di Cocco (INAF/IASF-Bo), A. Pellizzoni, A. Trois (INAF/OA-Cagliari), M. Pilia (ASTRON, the Netherlands), G. Barbiellini, F. Longo, E. Vallazza (INFN Trieste), A. Morselli, P. Picozza, (INFN and Univ. Roma Tor Vergata), M. Prest (Univ. dell'Insubria), P. Lipari, D. Zanello (INFN and Univ. Roma Sapienza), P. W. Cattaneo, A. Rappoldi (INFN Pavia), S. Colafrancesco (INAF-OAR and University of the Witwatersrand, Johannesburg), A. Antonelli (INAF/OAR and ASDC), P. Giommi (ASDC), L. Salotti, and G. Valentini (ASI)
on 4 Mar 2013; 22:15 UT
Credential Certification: Edoardo Striani (edoardo.striani@iasf-roma.inaf.it)

Subjects: Gamma Ray, Request for Observations, Neutron Star, Transient, Pulsar

Integrating from 2013-03-03 05:30 UT to 2013-03-04 11:00 UT, AGILE/GRID detects enhanced gamma-ray emission from a source positionally consistent with the Crab Nebula. The total (pulsar + Nebula) gamma-ray flux is: F = (740 +/- 220) x 10^-8 ph cm^-2 s^-1 (E > 100 MeV) at 6 sigma statistical significance, in agreement with the Fermi LAT detection (ATel #4855). AGILE is currently monitoring the Crab with telemetry gaps due to intermittent data acquisition at the ground station. Multifrequency observations of the Crab are strongly encouraged.

 

AGILE detection of a new gamma-ray source at high Galactic latitude, AGLJ1647+5107

ATel #4842; A. Bulgarelli, F. Gianotti, M. Trifoglio, V. Fioretti (INAF/IASF-Bo), F. Verrecchia, C. Pittori, F. Lucarelli (ASDC and INAF/OAR), E. Striani (Univ. Roma Tor Vergata), M. Cardillo (INAF/IAPS and Univ. Roma Tor Vergata), M. Tavani (INAF/IAPS, and Univ. Roma Tor Vergata), G. Piano (INAF/IAPS), I. Donnarumma (INAF/IAPS), S. Vercellone (INAF/IASF-Pa), A. Chen, A. Giuliani, S. Mereghetti, P. Caraveo, F. Perotti (INAF/IASF-Mi), F. D'Ammando (INAF/IRA-Bo), E. Del Monte, Y. Evangelista, M. Feroci, F. Lazzarotto, L. Pacciani, P. Soffitta, E. Costa, I. Lapshov, M. Rapisarda, A. Argan, G. Pucella, S. Sabatini, A. Trois, V. Vittorini (INAF/IAPS), F. Fuschino, M. Galli, C. Labanti, M. Marisaldi, G. Di Cocco (INAF/IASF-Bo), A. Pellizzoni (INAF/OA-Cagliari), M. Pilia (ASTRON, the Netherlands), G. Barbiellini, F. Longo, E. Vallazza (INFN Trieste), A. Morselli, P. Picozza, (INFN and Univ. Roma Tor Vergata), M. Prest (Univ. dell'Insubria), P. Lipari, D. Zanello (INFN and Univ. Roma Sapienza), P. W. Cattaneo, A. Rappoldi (INFN Pavia), S. Colafrancesco (INAF-OAR and University of the Witwatersrand, Johannesburg), P. Santolamazza (ASDC and INAF/OAR), P. Giommi (ASDC), L. Salotti, and G. Valentini (ASI)
on 26 Feb 2013; 21:21 UT
Credential Certification: Andrea Bulgarelli (bulgarelli@iasfbo.inaf.it)

Subjects: Gamma Ray, Transient

AGILE is detecting intense gamma-ray emission above 100 MeV from an unidentified source, AGLJ1647+5107, at Galactic coordinates (l,b)=(78.31, 40.00) +/- 0.5 deg (95% stat.) +/- 0.1 deg (syst.) (R.A., Dec.= 251.85 51.11 deg, J2000). Integrating from 2013-02-22 15:00 UT to 2013-02-24 17:18 UT, a maximum likelihood analysis yields the detection of a source with a flux of (200+/-50) x 10E-8 ph/cm2/s (E > 100 MeV) with a significance level of 5.4 sigma. No obvious counterpart is identified within the error box. This measurement was obtained with AGILE observing a large portion of the sky in spinning mode. Multifrequency observations of sources in the AGILE error circle are strong encouraged.

 

AGILE detection of enhanced gamma-ray emission from a position consistent with the blazar 4C +38.41

ATel #4389; F. Verrecchia, F. Lucarelli (ASDC and INAF/OAR), A. Bulgarelli (INAF/IASF-Bo), G. Piano (INAF/IAPS), M. Tavani (INAF/IAPS, and Univ. Roma Tor Vergata), S. Vercellone (INAF/IASF-Pa), I. Donnarumma (INAF/IAPS), E. Striani (Univ. Roma Tor Vergata), M. Cardillo (INAF/IAPS and Univ. Roma Tor Vergata), F. Gianotti, M. Trifoglio (INAF/IASF-Bo), A. Chen, A. Giuliani, S. Mereghetti, P. Caraveo, F. Perotti (INAF/IASF-Mi), S. Colafrancesco (INAF/OAR and Wits University), E. Del Monte, Y. Evangelista, M. Feroci, F. Lazzarotto, L. Pacciani, P. Soffitta, E. Costa, I. Lapshov, M. Rapisarda, A. Argan, G. Pucella, S. Sabatini, A. Trois, V. Vittorini (INAF/IAPS), F. Fuschino, M. Galli, C. Labanti, M. Marisaldi, G. Di Cocco (INAF/IASF-Bo), A. Pellizzoni (INAF/OA-Cagliari), M. Pilia (ASTRON, the Netherlands), G. Barbiellini, F. Longo, E. Vallazza (INFN Trieste), A. Morselli, P. Picozza, (INFN and Univ. Roma Tor Vergata), M. Prest (Univ. dell'Insubria), P. Lipari, D. Zanello (INFN and Univ. Roma Sapienza), P. W. Cattaneo, A. Rappoldi (INFN Pavia), C. Pittori, P. Santolamazza (ASDC and INAF/OAR), P. Giommi (ASDC), L. Salotti, and G. Valentini (ASI)
on 18 Sep 2012; 17:03 UT
Credential Certification: Francesco Verrecchia (francesco.verrecchia@asdc.asi.it)

Subjects: Gamma Ray, >GeV, AGN, Blazar, Transient

The AGILE satellite detected gamma-ray emission above 100 MeV from the position (l,b)=(60.25,42.60) +/- 0.5 deg (95% stat.) +/- 0.1 deg (syst.) (R.A., Dec.=248.44, 37.54 deg, J2000), positionally consistent with the flat spectrum radio quasar 4C +38.41 (also known as BZQ J1635+3808/3EG J1635+3813), and associated to the gamma-ray source 2FGL J1635.2+3810 included in the second Fermi catalog. A maximum likelihood analysis of the AGILE-GRID data in the integration between 2012-09-15 22:00 UT and 2012-09-18 10:30 UT, gives a significance level of 6.5 sigma with a flux of (290 +/- 80) x 10^-8 ph/cm^-2/s^-1 (E > 100 MeV). A flare from this source was detected by Fermi-LAT on May 9, 2011 (ATel #3333), reporting a peak flux of (210 +/- 30) x 10^-8 ph/cm^-2/s^-1 (E > 100 MeV). This measurement was obtained with AGILE observing a large portion of the sky in spinning mode. Multifrequency observations of the blazar 4C +38.41 region are strongly encouraged.

 

AGILE confirmation of the increasing gamma-ray activity from PKS 2233-148

ATel #4154; F. Lucarelli, F. Verrecchia, C. Pittori (ASDC and INAF/OAR), A. Bulgarelli, F. Gianotti, M. Trifoglio (INAF/IASF-Bo), G. Piano (INAF/IAPS), E. Striani (Univ. Roma Tor Vergata), M. Cardillo (INAF/IAPS and Univ. Roma Tor Vergata), I. Donnarumma (INAF/IAPS), M. Tavani (INAF/IAPS, and Univ. Roma Tor Vergata), S. Vercellone (INAF/IASF-Pa), A. Chen, A. Giuliani, S. Mereghetti, P. Caraveo, F. Perotti (INAF/IASF-Mi), S. Colafrancesco (INAF/OAR and Wits University), E. Del Monte, Y. Evangelista, M. Feroci, F. Lazzarotto, L. Pacciani, P. Soffitta, E. Costa, I. Lapshov, M. Rapisarda, A. Argan, G. Pucella, S. Sabatini, A. Trois, V. Vittorini (INAF/IAPS), F. Fuschino, M. Galli, C. Labanti, M. Marisaldi, G. Di Cocco (INAF/IASF-Bo), A. Pellizzoni (INAF/OA-Cagliari), M. Pilia (ASTRON, the Netherlands), G. Barbiellini, F. Longo, E. Vallazza (INFN Trieste), A. Morselli, P. Picozza, (INFN and Univ. Roma Tor Vergata), M. Prest (Univ. dell'Insubria), P. Lipari, D. Zanello (INFN and Univ. Roma Sapienza), P. W. Cattaneo, A. Rappoldi (INFN Pavia), P. Santolamazza (ASDC and INAF/OAR), P. Giommi (ASDC), L. Salotti, and G. Valentini (ASI)
on 6 Jun 2012; 17:15 UT
Credential Certification: Francesco Verrecchia (francesco.verrecchia@asdc.asi.it)

Subjects: Gamma Ray, >GeV, Request for Observations, AGN, Blazar

AGILE confirms the increasing gamma-ray activity from the BL Lac object PKS 2233-148 (also known as BZB J2236-1433 (Massaro et al., 2011, A&A 495)) as reported by Fermi-LAT in Atel #4152. Integrating from 2012-06-03 10:00 UT to 2012-06-05 22:00 UT, a maximum likelihood analysis yields a detection at a significance level above 5 sigma and a flux of (240 +/- 70) x 10E-8 ph/cm2/s (E > 100 MeV) at Galactic coordinates (l,b)=(48.47, -56.95) +/- 0.9 deg (95% stat.) +/- 0.1 deg (syst.) (R.A., Dec.= 339.97, -14.61 deg, J2000). The peak of the AGILE excess is found at around 0.5 deg from the position of PKS 2233-148 reported in Petrov et al. 2008 (AJ, 136, 580). This measurement was obtained with AGILE observing a large portion of the sky in spinning mode. Multifrequency observations of PKS 2233-148 are strongly encouraged.

 

AGILE detection of increasing gamma-ray emission from the FSRQ PKS1510-089

ATel #4153; F. Lucarelli, F. Verrecchia, C. Pittori (ASDC and INAF/OAR), G. Piano (INAF/IAPS), E. Striani (Univ. Roma Tor Vergata), M. Cardillo (INAF/IAPS and Univ. Roma Tor Vergata), I. Donnarumma (INAF/IAPS), M. Tavani (INAF/IAPS, and Univ. Roma Tor Vergata), S. Vercellone (INAF/IASF-Pa), A. Bulgarelli, F. Gianotti, M. Trifoglio (INAF/IASF-Bo), A. Chen, A. Giuliani, S. Mereghetti, P. Caraveo, F. Perotti (INAF/IASF-Mi), F. D'Ammando (INAF/IASF-Pa), E. Del Monte, Y. Evangelista, M. Feroci, F. Lazzarotto, L. Pacciani, P. Soffitta, E. Costa, I. Lapshov, M. Rapisarda, A. Argan, G. Pucella, S. Sabatini, A. Trois, V. Vittorini (INAF/IAPS), F. Fuschino, M. Galli, C. Labanti, M. Marisaldi, G. Di Cocco (INAF/IASF-Bo), A. Pellizzoni (INAF/OA-Cagliari), M. Pilia (ASTRON, the Netherlands), G. Barbiellini, F. Longo, E. Moretti, E. Vallazza (INFN Trieste), A. Morselli, P. Picozza, (INFN and Univ. Roma Tor Vergata), M. Prest (Univ. dell'Insubria), P. Lipari, D. Zanello (INFN and Univ. Roma Sapienza), P. W. Cattaneo, A. Rappoldi (INFN Pavia), P. Santolamazza (ASDC and INAF/OAR), P. Giommi (ASDC), L. Salotti, and G. Valentini (ASI)
on 5 Jun 2012; 18:30 UT
Credential Certification: Francesco Verrecchia (francesco.verrecchia@asdc.asi.it)

Subjects: Gamma Ray, >GeV, Request for Observations, AGN, Blazar, Transient

AGILE is detecting intense gamma-ray emission above 100 MeV from a source at Galactic coordinates (l,b)=(70.77, 22.82) +/- 0.8 deg (95% stat.) +/- 0.1 deg (syst.) (R.A., Dec.= 276.02, 42.85 deg, J2000). Integrating from 2012-06-03 04:00 UT to 2012-06-05 04:00 UT, a maximum likelihood analysis yields a detection at a significance level of 5 sigma and a flux of (260+/-90) x 10E-8 ph/cm2/s (E > 100 MeV). The AGILE detection is positionally consistent with the gamma-ray source 2FGL J1823.8+4312 (Abdo et a. 2011) classified as AGN of unknown type. This measurement was obtained with AGILE observing a large portion of the sky in spinning mode. Multifrequency observations of the AGILE error circle are strong encouraged.

 

Swift follow-up observations of renewed gamma-ray emission from the FSRQ PKS 1510-089

ATel #3939; S. Vercellone, P. Romano (INAF/IASF-Pa), F. Verrecchia, F. Lucarelli, C. Pittori (ASDC and INAF/OAR), G. Piano (INAF/IAPS), E. Striani (Univ. Roma Tor Vergata), M. Cardillo (INAF/IAPS and Univ. Roma Tor Vergata), I. Donnarumma (INAF/IAPS), A. Bulgarelli (INAF/IASF-Bo) and M. Tavani (INAF/IAPS and Univ. Roma Tor Vergata) on behalf of the AGILE Team
on 23 Feb 2012; 12:55 UT
Credential Certification: Stefano Vercellone (stefano@ifc.inaf.it)

Subjects: Optical, Ultra-Violet, X-ray, Gamma Ray, AGN, Blazar

Following the AGILE/GRID detection of renewed gamma-ray emission from the FSRQ PKS 1510-089 (Lucarelli et al. 2012, ATel #3934), we performed a Swift Target of Opportunity observation (ToO) monitoring campaign. We report the preliminary results of the observations performed from 2012-02-17 to 2012-02-19 (6.6ks on source). The XRT spectrum obtained combining the first 3.8ks fitted with an absorbed power law with an absorbing column density fixed to the Galactic value of 6.89E20 cm-2 (Kalberla et al. 2005) yields a photon index of 1.7+/-0.1,and an average flux of F=5.1E-12 erg/cm2/s (2-10 keV, unabsorbed). The XRT spectrum obtained combining the last 2.8ks yields a photon index of 1.6+/-0.1, and an average flux of F=5.4E-12 erg/cm2/s (2-10 keV, unabsorbed).The UVOT observed the field simultaneously with the XRT in the1 following optical and UV filters. The preliminary observed magnitudes in the Vega system are:
MJD Filter Magnitude
55974.9425+/-0.0006 B 16.52+/-0.05 (stat) +/-0.02 (sys)
55974.9407+/-0.0012 U 15.63+/-0.03 (stat) +/-0.02 (sys)
55974.9692+/-0.0345 W1 15.74+/-0.03 (stat) +/-0.03 (sys)

55976.0868+/-0.0007 B 16.55+/-0.04 (stat) +/-0.02 (sys)
55976.0853+/-0.0007 U 15.68+/-0.04 (stat) +/-0.02 (sys)
55976.0830+/-0.0015 W1 15.84+/-0.04 (stat) +/-0.03 (sys)
55976.0903+/-0.0027 W2 15.82+/-0.03 (stat) +/-0.03 (sys)

55976.5556+/-0.0719 V 16.22+/-0.06 (stat) +/-0.01 (sys)
55976.5510+/-0.0696 B 16.48+/-0.04 (stat) +/-0.02 (sys)
55976.5501+/-0.0691 U 15.60+/-0.04 (stat) +/-0.02 (sys)
55976.5489+/-0.0689 W1 15.73+/-0.04 (stat) +/-0.03 (sys)
55976.5588+/-0.0746 M2 15.67+/-0.04 (stat) +/-0.03 (sys)
55976.5540+/-0.0721 W2 15.76+/-0.03 (stat) +/-0.03 (sys)

55976.7634+/-0.0683 V 16.30+/-0.05 (stat) +/-0.01 (sys)
55976.7584+/-0.0687 B 16.52+/-0.03 (stat) +/-0.02 (sys)
55976.7574+/-0.0688 U 15.65+/-0.03 (stat) +/-0.02 (sys)
55976.7558+/-0.0694 W1 15.75+/-0.03 (stat) +/-0.03 (sys)
55976.7652+/-0.0689 M2 15.70+/-0.04 (stat) +/-0.03 (sys)
55976.7608+/-0.0699 W2 15.81+/-0.03 (stat) +/-0.03 (sys)

The magnitudes in the table are not corrected for the Galactic extinction due to a reddening of E(B-V) = 0.097 mag in the direction of the source (Schlegel et al. 1998). We can compare our preliminary results with those reported in Vercellone et al., 2012, ATel #3910. We note that the current X-ray flux level is about a factor of two lower than that previously reported, while the photon index is marginally softer. The values reported here are in agreement with the harder-when-brighter trend reported in D'Ammando et al., (2011, A&A, 529, A145). Moreover, we report a brightening of the source in the UV-optical bands (about 0.2 - 0.3 mag) with respect to the 2012 February 2 values. We warmly thank N. Gehrels, the Science Planners, and the Observatory Duty Scientists for having scheduled these observations.

 

AGILE detection of increasing gamma-ray emission from the FSRQ PKS1510-089

ATel #3934; F. Lucarelli (ASDC), G. Piano (INAF/IASF-Rm), F. Verrecchia (ASDC), E. Striani (Univ. Roma Tor Vergata), M. Cardillo (INAF/IASF-Rm and Univ. Tor Vergata), I. Donnarumma (INAF/IASF-Rm), S. Vercellone (INAF/IASF-Pa), M. Tavani (INAF/IASF-Rm and Univ. Tor Vergata), C. Pittori (ASDC), A. Bulgarelli, F. Gianotti, M. Trifoglio (INAF/IASF-Bo), A. Chen, A. Giuliani, S. Mereghetti, P. Caraveo, F. Perotti (INAF/IASF-Mi), S. Colafrancesco (INAF/OAR and Wits University), G. Pucella (ENEA), E. Del Monte, Y. Evangelista, M. Feroci, F. Lazzarotto, L. Pacciani, P. Soffitta, E. Costa, I. Lapshov, M. Rapisarda, A. Argan, Sabatini, A. Trois, V. Vittorini (INAF/IASF-Rm), F. Fuschino, M. Galli, C. Labanti, M. Marisaldi, G. Di Cocco (INAF/IASF-Bo), A. Pellizzoni, M. Pilia (INAF/OA-Cagliari), G. Barbiellini, E. Vallazza (INFN Trieste), F. Longo (Univ. Trieste and INFN Trieste), A. Morselli, P. Picozza (INFN and Univ. Roma Tor Vergata), M. Prest (Univ. dell'Insubria), P. Lipari, D. Zanello (INFN and Univ. Roma Sapienza), P. W. Cattaneo, A. Rappoldi (INFN Pavia), P. Santolamazza, P. Giommi (ASDC), L. Salotti and G. Valentini (ASI)
on 317 Feb 2012; 15:16 UT
Credential Certification: Fabrizio Lucarelli (fabrizio.lucarelli@asdc.asi.it)

Subjects: Gamma Ray, >GeV, Request for Observations, Blazar, Transient

AGILE is detecting intense gamma-ray emission above 100 MeV from a source whose position is consistent with the flat spectrum radio quasar PKS 1510-089 (also known as BZQ J1512-0905; coordinates: R.A. = 15h 12m 50.5s, Dec. =-09d 05m 59.8s, J2000). Integrating from 2012-02-14 04:00 UT to 2012-02-17 04:30 UT, a maximum likelihood analysis yields a detection at a significance level of 7.3 sigma and a flux of (380+/-90) x 10E-8 ph/cm2/s (E > 100 MeV). An integration of about 24h, from 2012-02-16 02:00 UT to 2012-02-17 03:30 UT, yields a detection of 6.7 sigma and a flux of (610+/-170) x 10E-8 ph/cm2/s (E > 100 MeV). The gamma-ray flux of the source is currently increasing. A previous increase of the gamma-ray flux has been recently reported by AGILE (ATel #3907), followed by a Swift ToO observation (ATel #3910). This measurement was obtained with AGILE observing a large portion of the sky in spinning mode. Multifrequency observations of the blazar PKS 1510-089 are strongly encouraged.

 

Swift follow-up observation of the detection of a gamma-ray enhanced emission from the FSRQ PKS 1510-089

ATel #3910; S. Vercellone, P. Romano (INAF/IASF-Pa), F. Verrecchia, C. Pittori (ASDC), M. Cardillo (INAF/IASF-Rm and Univ. Roma Tor Vergata), E. Striani (Univ. Roma Tor Vergata), I. Donnarumma (INAF/IASF-Rm), A. Bulgarelli (INAF/IASF-Bo) and M. Tavani (INAF/IASF-Rm and Univ. Tor Vergata) on behalf of the AGILE Team
on 3 Feb 2012; 17:18 UT
Credential Certification: Stefano Vercellone (stefano@ifc.inaf.it)

Subjects: Optical, Ultra-Violet, X-ray, Gamma Ray, AGN, Blazar

Following the AGILE/GRID detection of a gamma-ray enhanced emission from the FSRQ PKS 1510-089 (Verrecchia et al. 2012, ATel #3907), we performed a Swift target of opportunity observation. Swift observed PKS 1510-089 from 2012-02-02 19:49:09 to 2012-02-02 20:30:29 UT for about 2.5 ks. The XRT spectrum (PC data, 2.4 ks integration) fitted with an absorbed power law with an absorbing column density fixed to the Galactic value of 6.89E20 cm-2 (Kalberla et al. 2005) yields a photon index of 1.3+/-0.2, and an average flux of F=9.7E-12 erg/cm2/s (2-10 keV, unabsorbed). The UVOT observed the field simultaneously with the XRT in all optical and UV filters. The preliminary observed magnitudes in the Vega system are:
V 16.69+/-0.06 (stat) +/-0.01 (sys)
B 16.80+/-0.04 (stat) +/-0.02 (sys)
U 15.79+/-0.04 (stat) +/-0.02 (sys)
UVW1 15.98+/-0.04 (stat) +/-0.03 (sys)
UVM2 15.88+/-0.03 (stat) +/-0.03 (sys)
UVW2 15.91+/-0.03 (stat) +/-0.03 (sys)
The magnitudes in the table are not corrected for the Galactic extinction due to a reddening of E(B-V) = 0.097 mag in the direction of the source (Schlegel et al. 1998). We can compare our preliminary results with those discussed in D'Ammando et al., (2011, A&A, 529, A145) obtained during a very high and prolonged gamma-ray state in 2009 March, when PKS 1510-089 reached a gamma-ray peak flux of F=(702+/-131)E-8 ph/cm2/s (E>100 MeV), about a factor of 2.8 higher than that reported in ATel #3907. We note that our current X-ray flux F=1.3E-11 (0.3-10 keV, unabsorbed) and photon index, 1.3+/-0.2, are consistent with the harder-when-brighter trend reported in Figure 2 of D'Ammando et al. (2011). We warmly thank N. Gehrels, the Science Planners, and the Observatory Duty Scientists for having scheduled this observation in such a timely way.

 

AGILE detects enhanced gamma-ray emission from the FSRQ PKS 1510-089

ATel #3907; F. Verrecchia, C. Pittori (ASDC), M. Cardillo (INAF/IASF-Rm and Univ. Tor Vergata), E. Striani (Univ. Roma Tor Vergata), I. Donnarumma (INAF/IASF-Rm), S. Vercellone (INAF/IASF-Pa), M. Tavani (INAF/IASF-Rm, and Univ. Tor Vergata), A. Bulgarelli, F. Gianotti, M. Trifoglio (INAF/IASF-Bo), A. Chen, A. Giuliani, S. Mereghetti, P. Caraveo, F. Perotti (INAF/IASF-Mi),F. D'Ammando (INAF/IASF-Pa), E. Del Monte, Y. Evangelista, M. Feroci, F. Lazzarotto, L. Pacciani, P. Soffitta, E. Costa, I. Lapshov, M. Rapisarda, A. Argan, G. Piano, S. Sabatini, A. Trois, V. Vittorini (INAF/IASF-Rm), G. Pucella (ENEA), F. Fuschino, M. Galli, C. Labanti, M. Marisaldi, G. Di Cocco (INAF/IASF-Bo), A. Pellizzoni, M. Pilia (INAF/OA-Cagliari), G. Barbiellini (INFN Trieste), F. Longo (Univ Trieste and INFN Trieste), E. Moretti, E. Vallazza (INFN Trieste), A. Morselli, P. Picozza, (INFN and Univ. Roma Tor Vergata), M. Prest (Univ. dell'Insubria), P. Lipari, D. Zanello (INFN and Univ. Roma Sapienza), P. W. Cattaneo, A. Rappoldi (INFN Pavia), F. Lucarelli, P. Santolamazza, P. Giommi (ASDC), L. Salotti and G. Valentini (ASI)
on 2 Feb 2012; 12:41 UT
Credential Certification: Carlotta Pittori (carlotta.pittori@asdc.asi.it)

Subjects: Gamma Ray, >GeV, AGN, Blazar, Quasar

AGILE is detecting enhanced gamma-ray emission above 100 MeV from a position consistent with the flat spectrum radio quasar PKS 1510-089 (also known as BZQ J1512-0905, coordinates: R.A. = 15h 12m 50.5s, Dec. =-09d 05m 59.8s, J2000). Integrating from 2012-01-28 12:00 UT to 2012-02-01 12:00 UT, a maximum likelihood analysis yields a detection at a significance level of above 7 sigma and an average flux of (250+/-60) x 10E-8 ph/cm2/s (E > 100 MeV). The gamma-ray flux is currently increasing. An increase in the radio flux density at 43 GHz from this source during the second semester of 2011 has been recently reported in ATel #3799 (P. P. Beaklini et al.). This measurement was obtained with AGILE observing a large portion of the sky in spinning mode. Multifrequency observations of the blazar PKS 1510-089 are strongly encouraged.

 

AGILE detection of a high Galactic latitude gamma-ray source

ATel #3862; M. Cardillo (INAF/IASF-Rm and Univ. Tor Vergata), F. Verrecchia (ASDC), A. Bulgarelli (INAF/IASF-Bo), C. Pittori (ASDC), M. Tavani (INAF/IASF-Rm, and Univ. Tor Vergata), E. Striani (Univ. Roma Tor Vergata), G. Piano (INAF/IASF-Rm), F. Lucarelli (ASDC), I. Donnarumma (INAF/IASF-Rm), S. Vercellone (INAF/IASF-Pa), F. Gianotti, M. Trifoglio (INAF/IASF-Bo), A. Chen, A. Giuliani, S. Mereghetti, P. Caraveo, F. Perotti (INAF/IASF-Mi), F. D'Ammando (INAF/IASF-Pa), E. Del Monte, Y. Evangelista, M. Feroci, F. Lazzarotto, L. Pacciani, P. Soffitta, E. Costa, I. Lapshov, M. Rapisarda, A. Argan, G. Pucella, S. Sabatini, A. Trois, V. Vittorini (INAF/IASF-Rm), F. Fuschino, M. Galli, C. Labanti, M. Marisaldi, G. Di Cocco (INAF/IASF-Bo), A. Pellizzoni, M. Pilia (INAF/OA-Cagliari), G. Barbiellini, F. Longo, E. Moretti, E. Vallazza (INFN Trieste), A. Morselli, P. Picozza, (INFN and Univ. Roma Tor Vergata), M. Prest(Universita` dell'Insubria), P. Lipari, D. Zanello (INFN and Univ. Roma Sapienza), P. W. Cattaneo, A. Rappoldi (INFN Pavia), C. Pittori (ASDC), P. Santolamazza, P. Giommi (ASDC), L. Salotti, and G. Valentini (ASI)
on 12 Jan 2012; 19:32 UT
Credential Certification: Andrea Bulgarelli (bulgarelli@iasfbo.inaf.it)

Subjects: Gamma Ray, Transient

AGILE detected gamma-ray emission above 100 MeV from a source at Galactic coordinates (l,b) = (81.6 39.1)+/-0.7 deg (95% stat.) +/- 0.1 deg (sist.) (R.A.,Dec.=252.9, 53.7 deg, J2000). Integrating from 2012-01-09 11:26 UT until 2012-01-11 10:57 UT, a maximum likelihood analysis yields a detection at a significance level larger than 5 sigma and a flux F = (280 +/- 90) E-08 ph/cm2/s (E > 100 MeV). There is evidence that the most of the emission is for E<400 MeV. Just outside our error box there are two sources: the Fermi-LAT source 2FGL J1649.6+5238 and the FSRQ BZQ J1656+5321. Multifrequency observations of this region are strongly encouraged. This measurement was obtained by AGILE observing a large portion of the sky in spinning mode.

 

Gamma-ray activity of the blazar PKS 0402-362 detected by AGILE

ATel #3858; C. Pittori, F. Lucarelli (ASDC), A. Bulgarelli, F. Gianotti, M. Trifoglio (INAF/IASF-Bo), E. Striani (Univ. Roma Tor Vergata), G. Piano (INAF/IASF-Rm), I. Donnarumma (INAF/IASF-Rm), S. Vercellone (INAF/IASF-Pa), A. Chen, A. Giuliani, S. Mereghetti, P. Caraveo, F. Perotti (INAF/IASF-Mi), E. Del Monte, Y. Evangelista, M. Feroci, F. Lazzarotto, L. Pacciani, P. Soffitta, E. Costa, I. Lapshov, M. Rapisarda, A. Argan, S. Sabatini, V. Vittorini (INAF/IASF-Rm), M. Cardillo, M. Tavani (INAF/IASF-Rm, and Univ. Tor Vergata), G. Pucella (ENEA), F. Fuschino, M. Galli, C. Labanti, M. Marisaldi, G. Di Cocco (INAF/IASF-Bo), A. Pellizzoni, M. Pilia, A. Trois (INAF/OA-Cagliari), G. Barbiellini (INFN Trieste), F. Longo (Univ Trieste and INFN Trieste), E. Vallazza (INFN Trieste), A. Morselli, P. Picozza, (INFN and Univ. Roma Tor Vergata), M. Prest (Universita` dell'Insubria), P. Lipari, D. Zanello (INFN and Univ. Roma Sapienza), P. W. Cattaneo, A. Rappoldi (INFN Pavia), S. Colafrancesco (INAF/OA-Roma and Wits University), F. Verrecchia, P. Santolamazza, P. Giommi (ASDC), L. Salotti and G. Valentini (ASI)
on 11 Jan 2012; 10:05 UT
Credential Certification: Carlotta Pittori (carlotta.pittori@asdc.asi.it)

Subjects: Radio, Gamma Ray, AGN, Blazar, Transient

The discovery of several flaring radio sources and blazars by the Catalina Real-time Transient Survey (CRTS) during the last few weeks was recently reported in ATel #3853. We performed a search for related gamma-ray flares in the AGILE data archive on all sources reported in the CRTS ATel. On November 17th, 2011 AGILE detected a transient gamma-ray emission above 100 MeV from a source at Galactic Coordinates (l,b) = (181.1,70.4) +/- 1.2 deg (95% stat.) +/- 0.1 deg (syst.) (R.A.,Dec. = 11h 28m 59.4s, +35d 56m 46.4s (J2000)). Integrating from 2011-11-17 00:00 UT to 2010-11-19 00:00 UT, a maximum likelihood analysis yields a source detection with a significance level of 4.7 sigma and with a flux (2.0+/- 0.7) x 10E-6 ph/cm2/s (E > 100 MeV). The AGILE detection is consistent both in position and time with the Catalina transient source CSS111117:112759+362029, associated with the blazar BZQJ1127+3620 and with the 2FGL J1127.6+3622 source. The recorded flux shows an increase by a factor of about 40 with respect to the 2-sigma upper limit of 5 x 10E-8 detected by AGILE during the period July 2007 - January 2011 for a non continuous exposure. The November 2011 measurement was obtained with AGILE observing a large portion of the sky in spinning mode.

 

Gamma-ray activity of the blazar PKS 0402-362 detected by AGILE

ATel #3658; M. Cardillo (INAF/IASF-Rm and Univ.Tor Vergata), E.Striani (Univ. Roma Tor Vergata), F.Verrecchia (ASDC), M.Tavani (INAF/IASF-Rm, and Univ. Tor Vergata), G.Piano (INAF/IASF-Rm), F. Lucarelli (ASDC), S. Vercellone (INAF/IASF-Pa), I. Donnarumma (INAF/IASF-Rm), A. Bulgarelli, F. Gianotti, M. Trifoglio (INAF/IASF-Bo), A. Chen, A. Giuliani, S. Mereghetti, P. Caraveo, F. Perotti (INAF/IASF-Mi), F. D'Ammando (INAF/IASF-Pa), E. Del Monte, Y. Evangelista, M. Feroci, F. Lazzarotto, L. Pacciani, P. Soffitta, E. Costa, I. Lapshov, M. Rapisarda, A. Argan,G. Pucella, S. Sabatini, A. Trois, V. Vittorini (INAF/IASF-Rm), F. Fuschino, M. Galli, C. Labanti, M. Marisaldi, G.Di Cocco (INAF/IASF-Bo), A. Pellizzoni, M. Pilia (INAF/OA-Cagliari), G. Barbiellini, F. Longo, E. Moretti, E. Vallazza (INFN Trieste), A. Morselli, P. Picozza, (INFN and Univ.Roma Tor Vergata), M. Prest(Universita` dell'Insubria), P. Lipari, D. Zanello (INFN and Univ. Roma Sapienza), P.W. Cattaneo, A. Rappoldi (INFN Pavia), C. Pittori (ASDC), P. Santolamazza, P. Giommi (ASDC), L. Salotti, and G. Valentini (ASI)
on 24 Sep 2011; 14:45 UT
Credential Certification: Marco Tavani (tavani@iasf-roma.inaf.it)

Subjects: Gamma Ray, Blazar, Transient

AGILE is currently detecting intense gamma-ray emission above 100 MeV from a source at Galactic coordinates (l,b) = (237.9, -48.6) (R.A.,Dec.=60.8,-36.2 deg, J2000) whose position is coincident with the blazar PKS 0402-362. Following the gamma-ray activity reported by Fermi LAT (peak flux of (3.8 +/- 0.5) x10^-6 ph cm^-2 s^-1 on September 22, 2011; ATel #3655) (which is confirmed by our analysis), AGILE is currently detecting increased gamma-ray emission from PKS 0402-362. Integrating from 2011-09-23 00:00 UT until 2011-09-24 00:00 UT, a maximum likelihood analysis yields a detection with a flux F = (770+/-240) E-08 ph/cm2/s (E > 100 MeV). Integrating from 2011-09-22 04:30 until 2011-09-24 04:00, we obtain a detection at a significance above 7 sigma and flux F = (610+/-150) 10E-8 ph/cm2/s (E > 100 MeV). We notice that both Fermi-LAT (ATel #2413) and AGILE (Atel #2484) reported in early 2010 gamma-ray flaring of the blazar PKS 0402-362 at flux levels lower (by a factor near 3) than the current value. This measurement was obtained by AGILE observing a large portion of the sky in spinning mode. Multifrequency observations of the blazar PKS 0402-362 region are strongly encouraged.

 

AGILE detects enhanced gamma-ray emission from a new unidentified source AGL 2103+5630

ATel #3544; A. Bulgarelli (INAF/IASF-Bo), C. Pittori, F. Verrecchia (ASDC), M. Tavani (INAF/IASF-Rm, and Univ. Tor Vergata), F. Gianotti, M. Trifoglio (INAF/IASF-Bo), A. Chen (INAF/IASF-Mi), F. Lucarelli (ASDC), E. Striani (Univ. Roma Tor Vergata), G. Piano (INAF/IASF-Rm), S. Vercellone (INAF/IASF-Pa), I. Donnarumma (INAF/IASF-Rm), A. Giuliani, S. Mereghetti, P. Caraveo, F. Perotti (INAF/IASF-Mi), E. Del Monte, Y. Evangelista, M. Feroci, F. Lazzarotto, L. Pacciani, P. Soffitta, E. Costa, I. Lapshov, M. Rapisarda, A. Argan,G. Pucella, S. Sabatini, A. Trois, V. Vittorini (INAF/IASF-Rm), F. Fuschino, M. Galli, C. Labanti, M. Marisaldi, G. Di Cocco (INAF/IASF-Bo), A. Pellizzoni, M. Pilia (INAF/OA-Cagliari), G. Barbiellini, F. Longo,E. Vallazza (INFN Trieste), A. Morselli, P. Picozza, (INFN and Univ. Roma Tor Vergata), M. Cardillo (INAF/IASF-Rm and Univ. Tor Vergata), M. Prest (Universita` dell'Insubria), P. Lipari, D. Zanello (INFN and Univ. Roma Sapienza), P.W. Cattaneo, A. Rappoldi (INFN Pavia), P. Santolamazza, P. Giommi (ASDC), L. Salotti and G. Valentini (ASI)
on 10 Aug 2011; 17:12 UT
Credential Certification: Andrea Bulgarelli (bulgarelli@iasfbo.inaf.it)

Subjects: Gamma Ray, >GeV, Transient
Referred to by ATel #: 3554

AGILE is detecting intense gamma-ray emission above 100 MeV from a source at Galactic coordinates (l,b) = (95.15, 6.49) +/- 0.53 deg (95% stat.) +/- 0.1 deg (syst.) (R.A.,Dec.=315.8, 56.5 deg, J2000). Integrating from 2011-08-08 04:10 UT to 2011-08-10 09:04 UT, a maximum likelihood analysis yields a detection at a significance level of 4.8 sigma and a flux of (300+/-90) x 10E-8 ph/cm2/s (E > 100 MeV). Integrating from 2011-07-22 10:46 UT to 2011-08-08 07:25 UT we obtain only a 95% C.L. upper limit of 21 x 10E-8 ph/cm2/s (E > 100 MeV). No prominent extra-Galactic or Galactic gamma-ray sources are known within the AGL 2103+5630 error box. This measurement was obtained with AGILE observing a large portion of the sky in spinning mode. Multifrequency observations of the AGILE source error circle are strongly encouraged.

 

AGILE detects enhanced gamma-ray emission from BZQ J1512-0905 (PKS1510-089)

ATel #3470; I. Donnarumma (INAF/IASF-Rm), F. Lucarelli (ASDC), S. Vercellone (INAF/IASF-Pa), M. Tavani (INAF/IASF-Rm, and Univ. Tor Vergata), A. Bulgarelli, F. Gianotti, M. Trifoglio (INAF/IASF-Bo), A. Chen, A. Giuliani, S. Mereghetti, P. Caraveo, F. Perotti (INAF/IASF-Mi), F. D'Ammando (INAF/IASF-Pa), E. Del Monte, Y. Evangelista, M. Feroci, F. Lazzarotto, L. Pacciani, P. Soffitta, E. Costa, I. Lapshov, M. Rapisarda, A. Argan, G. Piano, G. Pucella, S. Sabatini, A. Trois, V. Vittorini (INAF/IASF-Rm), F. Fuschino, M. Galli, C. Labanti, M. Marisaldi, G. Di Cocco (INAF/IASF-Bo), A. Pellizzoni, M. Pilia (INAF/OA-Cagliari), G. Barbiellini, F. Longo, E. Moretti, E. Vallazza (INFN Trieste), A. Morselli, P. Picozza (INFN and Univ. Roma Tor Vergata), M. Cardillo (INAF/IASF-Rm and Univ. Tor Vergata), E. Striani (Univ. Roma Tor Vergata), M. Prest (Universita` dell'Insubria), P. Lipari, D. Zanello (INFN and Univ. Roma Sapienza), P.W. Cattaneo, A. Rappoldi (INFN Pavia), C. Pittori, P. Santolamazza, F. Verrecchia, P. Giommi (ASDC), L. Salotti and G. Valentini (ASI)
on 4 Jul 2011; 11:41 UT
Credential Certification: Fabrizio Lucarelli (fabrizio.lucarelli@asdc.asi.it)

Subjects: Gamma Ray, >GeV, Request for Observations, Transient
Referred to by ATel #: 3473

AGILE is detecting intense gamma-ray emission above 100 MeV from a position consistent with the flat-spectrum radio quasar BZQ J1512-0905 (PKS1510-089) (VLBI coordinates (J2000): RA=15h 12m 50.5s,Dec.=-09d 05m 59.8s (Johnston et al. 1995, AJ, 110, 880)). Integrating from 2011-07-02 04:30 UT to 2011-07-04 04:30 UT, a maximum likelihood analysis yields a detection at a significance level above 7 sigma and a flux above 7.0 x 10E-6 ph/cm2/s (E>100 MeV). The flux reported above is consistent with the daily flare detected by Fermi/LAT in April 2009 (ATel #2033) and the flare peak recorded by AGILE in March 2009 (D'Ammando et al. 2011, A&A 529, 145). A preliminary spectral analysis performed between June 28th and July 4th, 2011, in the energy range 100 MeV-1 GeV, shows that the gamma-ray spectrum is well consistent with the one reported in D'Ammando et al. 2011 (A&A 529, 145)during the AGILE 2009 multi-frequency campaign. This measurement was obtained with AGILE observing a large portion of the sky in spinning mode. Multifrequency observations of BZQ J1512-0905 are strongly encouraged.

 

AGILE detects enhanced gamma-ray emission from the region of the Narrow-Line Sy1 PMN J0948+0022

ATel #3448; F. Lucarelli (ASDC), G. Piano (INAF/IASF-Rm), F. Verrecchia (ASDC), S. Vercellone (INAF/IASF-Pa), M. Tavani (INAF/IASF-Rm, and Univ. Tor Vergata), I. Donnarumma (INAF/IASF-Rm), A. Bulgarelli, F. Gianotti, M. Trifoglio (INAF/IASF-Bo), A. Chen, A. Giuliani, S. Mereghetti, P. Caraveo, F. Perotti (INAF/IASF-Mi),F. D'Ammando (INAF/IASF-Pa), E. Del Monte, Y. Evangelista, M. Feroci, F. Lazzarotto, L. Pacciani, P. Soffitta, E. Costa, I. Lapshov, M. Rapisarda, A. Argan,G. Pucella, S. Sabatini, A. Trois, V. Vittorini (INAF/IASF-Rm), F. Fuschino, M. Galli, C. Labanti, M. Marisaldi, G. Di Cocco (INAF/IASF-Bo), A. Pellizzoni, M. Pilia (INAF/OA-Cagliari), G. Barbiellini, F. Longo, E. Moretti, E. Vallazza (INFN Trieste), A. Morselli, P. Picozza, (INFN and Univ. Roma Tor Vergata), M. Cardillo (INAF/IASF-Rm and Univ. Tor Vergata), E. Striani (Univ. Roma Tor Vergata), M. Prest (Universita` dell'Insubria), P. Lipari, D. Zanello (INFN and Univ. Roma Sapienza), P.W. Cattaneo, A. Rappoldi (INFN Pavia), C. Pittori (ASDC),P. Santolamazza, S. Colafrancesco, P. Giommi (ASDC), L. Salotti and and G. Valentini (ASI)
on 22 Jun 2011; 17:43 UT
Credential Certification: Fabrizio Lucarelli (fabrizio.lucarelli@asdc.asi.it)

Subjects: Gamma Ray, >GeV, Request for Observations, AGN, Transient

AGILE is detecting intense gamma-ray emission above 100 MeV at Galactic coordinates (l,b) = (237.4, 38.4) +/- 0.9 deg (95% stat.) +/- 0.1 deg (syst.) (R.A.,Dec.=147.4,0.3 deg, J2000). Integrating from 2011-06-20 07:30 UT to 2011-06-22 11:20 UT, a maximum likelihood analysis yields a detection at a significance level of about 5 sigma and a flux of (310+/-100) x 10E-8 ph/cm2/s (E > 100 MeV). On a 10 days integration starting from June 10th, we obtain only a 95% C.L. upper limit of 60 x 10E-8 ph/cm2/s (E > 100 MeV). The AGILE source error box is consistent with the Narrow-Line Sy1 PMN J0948+0022 associated to the Fermi gamma-ray source 1FGL J0949.0+0021 (Abdo et al. 2010). A gamma-ray flux increase from this source has been recently reportedby Fermi/LAT on June 11, 2011 (ATel #3429). This measurement was obtained with AGILE observing a large portion of the sky in spinning mode. Multifrequency observations of the AGILE source error circle are strongly encouraged. References: Abdo et al., 2010, ApJS, 188, 405.

 

Enhanced gamma-ray emission detected by AGILE from the Cygnus X-3 region

ATel #3386; G. Piano, M. Tavani (INAF/IASF Roma), A. Bulgarelli (INAF/IASF Bologna), E. Striani, M. Cardillo (Univ. Tor Vergata), S. Sabatini (INAF/IASF Roma), F. Gianotti, M. Trifoglio (INAF/IASF Bologna), C. Pittori, F. Verrecchia, F. Lucarelli (ASDC), A. Argan, A. Trois, G. De Paris, E. Costa, I. Donnarumma, M. Feroci, L. Pacciani, E. Del Monte, F. Lazzarotto, P. Soffitta, Y. Evangelista, I. Lapshov, V. Vittorini, M. Giusti (INAF/IASF Roma), P. Caraveo, A. Chen, A. Giuliani, S. Mereghetti, F. Perotti (INAF/IASF Milano), M. Marisaldi, G. Di Cocco, C. Labanti, F. Fuschino, M. Galli (INAF/IASF Bologna), G. Pucella, M. Rapisarda (ENEA-Roma), S. Vercellone, F. D'Ammando (IASF-Pa), A. Pellizzoni, M. Pilia (INAF/OA-Cagliari), G. Barbiellini, F. Longo (INFN Trieste), P. Picozza, A. Morselli (INFN and Univ. Tor Vergata), M. Prest (Universita` dell'Insubria), P. Lipari, D. Zanello (INFN Roma-1), P.W. Cattaneo, A. Rappoldi (INFN Pavia), P. Giommi, P. Santolamazza (ASDC), G. Valentini, L. Salotti (ASI)
on 29 May 2011; 17:13 UT
Credential Certification: Marco Tavani (tavani@iasf-roma.inaf.it)

Subjects: X-ray, Gamma Ray, Transient
Referred to by ATel #: 3389

AGILE is detecting enhanced gamma-ray emission from a source positionally consistent with the microquasar Cygnus X-3. Integrating during the period 2011-05-28 07:58:37 UT to 2011-05-29 06:02:51 UT (MJD=55709.33-55710.25) the AGILE-GRID detected gamma-ray emission above 100 MeV from a source at Galactic coordinates (l, b) = (79.8, 0.3) +/- 0.8(stat.) +/- 0.1 (syst.) deg, and flux F > 300 x 10^-8 photons/cm^2/s above 100 MeV (1-day multi-source-analysis significance in spinning mode ~4 sigma). The multi-source likelihood analysis was carried out taking into account thegamma-ray sources in the field including the nearby pulsars (PSR J2021+3651, PSR J2021+4026, PSR J2032+4127). We notice that the hard X-ray lightcurve of Cygnus X-3 as monitored by the BAT/Swift instrument (public data available at http://heasarc.gsfc.nasa.gov/docs/swift/results/transients/CygX-3) shows an overall decreasing trend starting on MJD ~ 55680. This trend of decreasing hard X-ray emission in conjunction with gamma-ray flaring activity of Cygnus X-3 was already detected several times (Tavani et al., 2009). We strongly encourage multifrequency observations of Cygnus X-3.

 

AGILE detects enhanced gamma-ray emission from a new unidentified source AGL 2302-3251

ATel #3357; F. Lucarelli (ASDC), G. Piano (INAF/IASF-Rm), F. Verrecchia, C. Pittori (ASDC), M. Tavani (INAF/IASF-Rm and Univ. Tor Vergata), A. Bulgarelli, F. Gianotti, M. Trifoglio (INAF/IASF-Bo), A. Chen, A. Giuliani, S. Mereghetti, P. Caraveo, F. Perotti (INAF/IASF-Mi), F. D'Ammando, S. Vercellone (INAF/IASF-Pa), I. Donnarumma, E. Del Monte, Y. Evangelista, M. Feroci, F. Lazzarotto, L. Pacciani, P. Soffitta, E. Costa, I. Lapshov, M. Rapisarda, A. Argan, G. Pucella, S. Sabatini, A. Trois, V. Vittorini (INAF/IASF-Rm), F. Fuschino, M. Galli, C. Labanti, M. Marisaldi, G. Di Cocco (INAF/IASF-Bo), A. Pellizzoni, M. Pilia (INAF/OA-Cagliari), G. Barbiellini, F. Longo, E. Vallazza (INFN Trieste), E. Striani (Univ. Roma Tor Vergata), A. Morselli, P. Picozza (INFN and Univ. Roma Tor Vergata), M. Prest (Universita` dell'Insubria), P. Lipari, D. Zanello (INFN and Univ. Roma Sapienza), P.W. Cattaneo, A. Rappoldi (INFN Pavia), P. Santolamazza, P. Giommi (ASDC), L. Salotti, G. Valentini (ASI)
on 17 May 2011; 18:58 UT
Credential Certification: Fabrizio Lucarelli (fabrizio.lucarelli@asdc.asi.it)

Subjects: Gamma Ray, >GeV, Request for Observations, Transient

AGILE is detecting intense gamma-ray emission above 100 MeV at Galactic coordinates (l, b) = (12.7, -65.6) +/- 1.0 deg (95% stat.) +/- 0.1 deg (syst.) (R.A.,Dec.=(345.38, -32.85)deg, J2000). Integrating from 2011-05-14 03:00 UT to 2011-05-17 03:00 UT, a maximum likelihood analysis yields a detection at a significance level larger than 5 sigma and a flux above 200 x 10E-8 ph/cm2/s (E > 100 MeV). There is evidence tha most part of the emission is below 400MeV. No prominent extragalactic or Galactic sources are known within the AGL 2302-3251 error box. This measurement was obtained with AGILE observing a large portion of the sky in spinning mode. Multifrequency observations of the AGL 2302-3251 error circle are strongly encouraged.

 

AGILE monitoring of the strongly variable gamma-ray emission from the Crab Nebula

ATel #3286; E. Striani (Univ. Tor Vergata), G. Piano (INAF/IASF Roma), M. Tavani (INAF/IASF Roma and Univ. Tor Vergata), A. Bulgarelli (INAF/IASF Bologna), C. Pittori, F. Verrecchia (ASDC), V. Vittorini (INAF/IASF Roma), F. Gianotti, M. Trifoglio (INAF/IASF Bologna), A. Argan, A. Trois, G. De Paris, S. Sabatini, E. Costa, I. Donnarumma, M. Feroci, L. Pacciani, E. Del Monte, F. Lazzarotto, P. Soffitta, Y. Evangelista, I. Lapshov (INAF-IASF-Rm), P. Caraveo, A. Chen, A. Giuliani, S. Mereghetti, F. Perotti (INAF-IASF-Milano), M. Marisaldi, G. Di Cocco, C. Labanti, F. Fuschino, M. Galli (INAF/IASF Bologna), G. Pucella, M. Rapisarda (ENEA-Roma), S. Vercellone, F. D'Ammando (IASF-Pa), A. Pellizzoni, M. Pilia (INAF/OA-Cagliari), G. Barbiellini, F. Longo (INFN Trieste), P. Picozza, A. Morselli (INFN and Univ. Tor Vergata), M. Prest (Universita` dell'Insubria), P. Lipari, D. Zanello (INFN Roma-1), P.W. Cattaneo, A. Rappoldi (INFN Pavia), P. Giommi, P. Santolamazza, F. Lucarelli, (ASDC), G. Valentini, L. Salotti (ASI)
on 16 Apr 2011; 16:10 UT
Credential Certification: Marco Tavani (tavani@iasf-roma.inaf.it)

Subjects: Gamma Ray, Neutron Star, Supernova Remnant, Transient, Pulsar

Strongly variable gamma-ray emission above 100 MeV continues to be detected by AGILE from a source positionally consistent with the Crab Nebula. After a telemetry gap that AGILE experienced on April 14, 2011 (in partial coincidence with the strong gamma-ray flare reported by Fermi-LAT in ATel # 3284) the AGILE-GRID detected the following gamma-ray flux above 100 MeV (pulsar plus nebula): MJD=55666.44-55667.44, 2011-04-15 10:40 UT - 2011-04-16 10:38 UT, F = (19.6 +/- 3.7) 10^{-6} ph/cm^2/sec. (We recall that the long timescale average flux from the Crab pulsar + Nebula in the AGILE-GRID energy range above 100 MeV is F = (2.2 +/- 0.15) 10^{-6} ph/cm^2/sec). This extreme gamma-ray emission from the Crab Nebula follows the activity recently reported by Fermi-LAT and AGILE in ATels # 3276, # 3282, # 3284). Follow-up X-ray observations were carried out by Swift (ATel # 3279) as well as Chandra (ATel # 3283). The Crab Nebula is currently the brightest gamma-ray source in the sky with a flux approximately twice that of the Vela pulsar. Short-timescale variations of the AGILE gamma-ray signal show variability on a 12 hr timescale or less. Multifrequency observations of the Crab Nebula are crucial to monitor this remarkable state of emission, and we strongly encourage these observations despite the current unfavorable sky position of the Crab.

 

AGILE monitoring of the enhanced gamma-ray emission from the Crab Nebula region

ATel #3282; M. Tavani (INAF/IASF Roma and Univ. Tor Vergata), A. Bulgarelli (INAF/IASF Bologna), E. Striani (Univ. Tor Vergata), G. Piano, V. Vittorini (INAF/IASF Roma), F. Gianotti, M. Trifoglio (INAF/IASF Bologna), C. Pittori, F. Verrecchia (ASDC), A. Argan, A. Trois, G. De Paris, S. Sabatini, E. Costa, I. Donnarumma, M. Feroci, L. Pacciani, E. Del Monte, F. Lazzarotto, P. Soffitta, Y. Evangelista, I. Lapshov (INAF-IASF-Rm), P. Caraveo, A. Chen, A. Giuliani, S. Mereghetti, F. Perotti (INAF-IASF-Milano), M. Marisaldi, G. Di Cocco, C. Labanti, F. Fuschino, M. Galli (INAF/IASF Bologna), G. Pucella, M. Rapisarda (ENEA-Roma), S. Vercellone, F. D'Ammando (IASF-Pa), A. Pellizzoni, M. Pilia (INAF/OA-Cagliari), G. Barbiellini, F. Longo (INFN Trieste), P. Picozza, A. Morselli (INFN and Univ. Tor Vergata), M. Prest (Universita` dell'Insubria), P. Lipari, D. Zanello (INFN Roma-1), P.W. Cattaneo, A. Rappoldi (INFN Pavia), P. Giommi, P. Santolamazza, F. Lucarelli, (ASDC), G. Valentini, L. Salotti (ASI)
on 14 Apr 2011; 16:33 UT
Credential Certification: Marco Tavani (tavani@iasf-roma.inaf.it)

Subjects: Gamma Ray, Neutron Star, Supernova Remnant, Transient

AGILE is monitoring the gamma-ray emission from the Crab Nebula region, and enhanced flux above 100 MeV is currently detected from a source positionally consistent with the Crab Nebula. AGILE-GRID detected the following gamma-ray fluxes above 100 MeV (pulsar plus nebula): MJD=55660.9-55662.9, 2011-04-09 23:45 UT - 2011-04-11 23:45 UT, F = (3.5 +/- 1.3) 10^{-6} ph/cm^2/sec MJD=55662.9-55664.9, 2011-04-11 23:45 UT - 2011-04-13 23:45 UT, F = (6.5 +/- 1.5) 10^{-6} ph/cm^2/sec. (We recall that the long timescale average flux from the Crab pulsar + Nebula in the AGILE-GRID energy range above 100 MeV is F = (2.2 +/- 0.15) 10^{-6} ph/cm^2/sec). No significant flux variation is detected by AGILE during the 2-day interval MJD = 55660.9-55662.9 that includes the detection interval recently reported by Fermi-LAT (ATel # 3276). Significantly enhanced gamma-ray emission from the Crab Nebula above F = 5 10^{-6} ph/cm^2/sec (E > 100 MeV) is detected by AGILE on a 2-day timescale integration starting on April 12, 2011. Enhanced gamma-ray emission from the Crab Nebula is currently being detected by AGILE, with indications of short-timescale variations. We strongly encourage multifrequency observations of the Crab Nebula.

 

AGILE detection of Cygnus X-3 above 400 MeV

ATel #3239; A. Bulgarelli (INAF/IASF Bologna, Italy), E. Striani (Univ. Tor Vergata), G. Piano, M. Tavani (INAF/IASF Roma), F. Gianotti, M. Trifoglio (INAF/IASF Bologna), M. McCollough, P. Savolainen (Smithsonian Astrophys. Observatory, USA), A. Argan, A. Trois, G. De Paris, V. Vittorini, E. Costa, I. Donnarumma, M. Feroci, L. Pacciani, E. Del Monte, F. Lazzarotto, P. Soffitta, Y. Evangelista, I. Lapshov, S. Sabatini, M. Cardillo (INAF-IASF-Rm), A. Chen, A. Giuliani, S. Mereghetti, F. Perotti (INAF-IASF-Milano), M. Marisaldi, G. Di Cocco, C. Labanti, F. Fuschino, M. Galli (INAF/IASF Bologna), G. Pucella, M. Rapisarda (ENEA-Roma), F. D'Ammando, S. Vercellone (INAF/IASF Palermo), A. Pellizzoni, M. Pilia (INAF/OA-Cagliari), G. Barbiellini, F. Longo (INFN and University of Trieste), P. Picozza, A. Morselli (INFN and University of Rome Tor Vergata), M. Prest (University of Insubria, Como), P. Lipari, D. Zanello (INFN and University of Rome La Sapienza), P.W. Cattaneo, A. Rappoldi (INFN Pavia), C. Pittori, F. Verrecchia, F. Lucarelli, P. Giommi, P. Santolamazza, (ASDC), L. Salotti, G. Valentini (ASI)
on 26 Mar 2011; 20:52 UT
Credential Certification: Marco Tavani (tavani@iasf-roma.inaf.it)

Subjects: X-ray, Gamma Ray, Binary, Black Hole, Neutron Star, Transient

The AGILE satellite has been monitoring the Cygnus X-3 region in the spinning mode. The AGILE-GRID detector does not detect significant gamma-ray emission during the period of the Fermi-LAT detection on MJD 55642 (March 22, 2011, ATel #3233). Integrating during the period MJD 55641-55642 (a standard 2-day integration of the AGILE spinning mode) we obtain a 95% confidence level upper limit of 1.1 x 10^-6 ph cm^-2 s^-1 (E > 100 MeV). For E > 400 MeV, we obtain a 95% confidence level upper limit of 0.6 x 10^-6 ph cm^-2 s^-1. However, integrating during the period MJD 55639-55640 the AGILE-GRID multi-source likelihood analysis finds enhanced gamma-ray emission above 400 MeV from a source positionally consistent with Cygnus X-3 at Galactic coordinates (l,b)=(80.23, 0.46) +/- 0.6 degrees (statistical plus systematic error), (R.A.,Dec.) J2000 =(308.66, 41.12) with a flux F = (0.9 +/- 0.3)x10^-6 ph cm^-2 s^-1 at 3.9 standard deviation significance level. For E > 100 MeV, we obtain a marginal detection at a 3 standard deviation significance level with a flux F= (1.4 +/- 0.8) x 10^-6 ph cm^-2 s^-1. We note that this detection occurs a few days before the prominent hard-X ray flux rise shown by the Swift/BAT data near MJD 55643 after several weeks of low hard X-ray emission. On MJD 55643 a Swift pointed observation was performed. The spectrum can be adequately fit by an absorbed partial covered disk blackbody with an absorption edge near 7 keV (n_H = 2.6x10^{22} cm^{-2}, n_H(covering) = 4.9x10^{22} cm^{-2}, f_covering = 0.79, T_bb = 1.9 keV). The measured 1-8 keV flux is 7.35x10^{-9} ergs/s/cm^2 (unabsorbed: 1.56x10^{-8} ergs/s/cm^2). The Swift/BAT spectra can be described by a steep (-3.5) power law. Our detection at 400 MeV and lack of prominent emission in the 100-400 MeV energy band suggests a relatively hard gamma-ray spectrum of this remarkable event. The Cygnus X-3 spectral properties appear to be different from what detected by AGILE during the period preceding the strong radio flare and the hard X-ray spectral change of April 16-17, 2008, as reported in Tavani et al., Nature, 462, 620 (2009).

 

AGILE detects enhanced gamma-ray emission from a region including the BL Lac Object S4 1749+70

ATel #3199; F. Lucarelli, C. Pittori (ASDC), M. Cardillo (INAF/IASF-Rm and Univ. Tor Vergata), F. Verrecchia (ASDC), E. Striani (Univ. Roma Tor Vergata), M. Tavani (INAF/IASF-Rm, and Univ. Tor Vergata), S. Vercellone (INAF/IASF-Pa), A. Bulgarelli, F. Gianotti, M. Trifoglio (INAF/IASF-Bo), A. Chen, A. Giuliani, S. Mereghetti, P. Caraveo, F. Perotti (INAF/IASF-Mi), I. Donnarumma (INAF/IASF-Rm), F. D'Ammando (INAF/IASF-Pa), E. Del Monte, Y. Evangelista, M. Feroci, F. Lazzarotto, L. Pacciani, P. Soffitta, E. Costa, I. Lapshov, M. Rapisarda, A. Argan, G. Piano, G. Pucella, S. Sabatini, A. Trois, V. Vittorini (INAF/IASF-Rm), F. Fuschino, M. Galli, C. Labanti, M. Marisaldi, G. Di Cocco (INAF/IASF-Bo), A. Pellizzoni, M. Pilia (INAF/OA-Cagliari), G. Barbiellini, F. Longo, E. Moretti, E. Vallazza (INFN Trieste), A. Morselli, P. Picozza (INFN and Univ. Roma Tor Vergata), M. Prest (Universita` dell'Insubria), P. Lipari, D. Zanello (INFN and Univ. Roma Sapienza), P.W. Cattaneo, A. Rappoldi (INFN Pavia), P. Santolamazza, S. Colafrancesco, P. Giommi (ASDC), L. Salotti and and G. Valentini (ASI)
on 1 Mar 2011; 15:15 UT
Credential Certification: Fabrizio Lucarelli (fabrizio.lucarelli@asdc.asi.it)

Subjects: >GeV, AGN, Blazar

AGILE is detecting intense gamma-ray emission above 100 MeV at Galactic Coordinates (l, b) = (100.1, 30.7) +/- 0.8 deg (95% stat.) +/- 0.1 deg (syst.) (R.A.=17:49:7.5, Dec.=69:44:4.0, J2000). Integrating from 2011-02-26 00:00 UT to 2011-03-01 04:00 UT, a maximum likelihood analysis yields a detection at a significance level above 5 sigma and a flux F=(200 +/- 60) x 10E-8 ph/cm2/s (E > 100 MeV). We note that the BL Lac Object S4 1749+70 (also known as BZB J1748+7005) lies within the AGILE gamma-ray source error box. The measured flux is about a factor of two higher with respect to a previous detection reported in the same region by the Fermi Coll. on February 16, 2011 (ATel #3171). This measurement was obtained with AGILE observing a large portion of the sky in spinning mode. Multifrequency observations of the AGILE source error box are strongly encouraged.

 

Gamma-ray flaring emission from Cygnus X-3 detected by AGILE

ATel #3151; A. Bulgarelli (INAF/IASF Bologna, Italy), C. Pittori (ASDC), E. Striani (Univ. Tor Vergata), M. Tavani (INAF/IASF Roma), F. Gianotti, M. Trifoglio (INAF/IASF Bologna), G. Pooley (Cavendish Lab., Cambridge, UK), M. McCollough (Smithsonian Astrophys. Observatory, USA), Sergei A. Trushkin (Special Astrophysical Observatory, Russia), G. Piano (INAF/IASF Roma), F. Verrecchia, F. Lucarelli (ASDC), M. Cardillo (Univ. Tor Vergata), A. Argan, A. Trois, G. De Paris, V. Vittorini, E. Costa, I. Donnarumma, M. Feroci, L. Pacciani, E. Del Monte, F. Lazzarotto, P. Soffitta, Y. Evangelista, I. Lapshov, S. Sabatini (INAF-IASF-Rm), A. Chen, A. Giuliani(INAF-IASF-Milano), M. Marisaldi, G. Di Cocco, C. Labanti, F. Fuschino, M. Galli (INAF/IASF Bologna), P. Caraveo, S. Mereghetti, F. Perotti (INAF/IASF Milano), G. Pucella, M. Rapisarda (ENEA-Roma), F. D'Ammando, S. Vercellone (IASF-Pa), A. Pellizzoni, M. Pilia (INAF/OA-Cagliari), G. Barbiellini, F. Longo (INFN and Univ. Trieste), P. Picozza, A. Morselli (INFN and Univ. Tor Vergata), M. Prest (Universita` dell'Insubria), P. Lipari, D. Zanello (INFN Roma-1), P.W. Cattaneo, A. Rappoldi (INFN Pavia), P. Giommi, P. Santolamazza, (ASDC), L. Salotti, G. Valentini (ASI)
on 8 Feb 2011; 15:45 UT
Password Certification: Andrea Bulgarelli (bulgarelli@iasfbo.inaf.it)

Subjects: X-ray, >GeV, Binary, Transient

AGILE continues to detect gamma-ray flaring emission from a source positionally consistent with the microquasar Cygnus X-3. Integrating during the period 2011-02-06 05:00 UT to 2011-02-08 09:00 UT (MJD= 55598.21-55600.37) the AGILE-GRID multi-source likelihood analysis finds enhanced gamma-ray emission above 100 MeV from a source at Galactic coordinates (l,b) = (79.46, 0.6) +/- 0.7 (stat.) +/- 0.1 (syst.) deg, (R.A.,Dec.) J2000 = (307.91, 40.58) deg, with flux F > 250 e-8 ph/cm2/sec for a 4.8 sigma significance. On 2011-02-07 (MJD 55599) the Swift/BAT data indicate that Cygnus X-3 experienced a brief (~ 0.2 day) quenching in the hard X-ray. The Swift/BAT data indicate a trend of decreasing hard X-ray emission over the last several weeks. This gamma ray flaring activity follows the trend already reported in ATel #3141. In the following link a 1 day integration intensity map (2011-02-07 05:10 - 2011-02-08 05:50 UT) of the Cygnus region is available. We strongly encourage multifrequency observations of Cygnus X-3.

 

AGILE detection of enhanced gamma-ray emission from Cygnus X-3

ATel #3141; A. Bulgarelli (INAF/IASF Bologna, Italy), G. Piano, M. Tavani (INAF/IASF Roma), F. Gianotti, M. Trifoglio (INAF/IASF Bologna), G. Pooley (Cavendish Lab., Cambridge, UK), M. McCollough (Smithsonian Astrophys. Observatory, USA), Sergei A. Trushkin (Special Astrophysical Observatory, Russia), E. Striani (Univ. Tor Vergata), C. Pittori, F. Verrecchia, F. Lucarelli (ASDC), A. Argan, A. Trois, G. De Paris, V. Vittorini, E. Costa, I. Donnarumma, M. Feroci, L. Pacciani, E. Del Monte, F. Lazzarotto, P. Soffitta, Y. Evangelista, I. Lapshov, S. Sabatini (INAF-IASF-Rm), A. Chen, A. Giuliani(INAF-IASF-Milano), M. Marisaldi, G. Di Cocco, C. Labanti, F. Fuschino, M. Galli (INAF/IASF Bologna), P. Caraveo, S. Mereghetti, F. Perotti (INAF/IASF Milano), G. Pucella, M. Rapisarda (ENEA-Roma), F. D'Ammando, S. Vercellone (IASF-Pa), A. Pellizzoni, M. Pilia (INAF/OA-Cagliari), G. Barbiellini, F. Longo (INFN Trieste), P. Picozza, A. Morselli (INFN and Univ. Tor Vergata), M. Prest (Universita` dell'Insubria), P. Lipari, D. Zanello (INFN Roma-1), P.W. Cattaneo, A. Rappoldi (INFN Pavia), P. Giommi, P. Santolamazza, (ASDC), L. Salotti, G. Valentini (ASI)
on 1 Feb 2011; 21:31 UT
Password Certification: Marco Tavani (tavani@iasf-roma.inaf.it)

Subjects: Radio, X-ray, >GeV, Binary, Transient

AGILE is detecting an enhanced gamma-ray emission from a source positionally consistent with the microquasar Cygnus X-3. Integrating during the period 2011-01-27 20:00 UT to 2011-02-01 11:00 UT (MJD= 55588.83-55593.45) the AGILE-GRID multi-source likelihood analysis finds enhanced gamma-ray emission above 100 MeV from a source at Galactic coordinates (l,b) = (79.50,1.05) +/- 0.7 (stat.) +/- 0.1 (syst.) deg, (R.A.,Dec.) = (307.46, 40.89) deg, with flux F = (200 +/- 60) e-8 ph/cm2/sec above 100 MeV (about 4 sigma significance for the 1-day integration period between MJD 55592.375 and 55593.375). The AGILE exposure of Cygnus X-3 reported above covers the millimeter-wave radio flare period reported in the ATel #3130, and the radio observation of ATel #3135. We also report radio data obtained by the RATAN-600 telescope and AMI Large Array. RATAN-600 has been monitoring Cygnus X-3 daily from Jan. 8th until Jan. 31st, 2011, at 4.8, 7.7 and 11.2 GHz (typical flux errors near 5-10 per cent). The radio light curve of Cygnus X-3 shows inverted spectra with a typical spectral index near +1. The power-law fit spectrum of 28 Jan. 2011, when extrapolated to higher frequencies gives a flux near 2 Jy at 98 GHz. This value is consistent with the NRO data (ATel #3130). This activity is also consistent with an optical thick flare of flux fainter than 1 Jy at cm wavelengths. An AMI-LA measurement obtained on Feb. 1, 2011, gives a flux of about 350 mJy at 15 GHz. The hard X-ray flux of Cygnus X-3 from Swift/BAT shows over the last few months a downward trend towards a possible quenched state in the hard X-rays. There have been a few brief (~0.5 day) periods of very low hard X-ray flux during this period. The enhanced gamma-ray emission from Cygnus X-3 along with the recent spectral transition reported in the ATel 3139 appears to be following the trend that was identified in previous episodes of low hard X-ray emission (Tavani et al. 2009, Nature 462, 620; Abdo et al. 2009, Science 326, 1512; ATel #2609; ATel #2645). We strongly encourage multifrequency observations of Cygnus X-3.

 

AGILE detection of the transient gamma-ray source AGL J1037-5708

ATel #3059; A. Bulgarelli, F. Gianotti, M. Trifoglio (INAF/IASF-Bo), F. Lucarelli, F. Verrecchia, C. Pittori (ASDC), E. Striani, M. Tavani (INAF/IASF-Rm, and Univ. Tor Vergata), S. Vercellone (INAF/IASF-Pa), A. Chen, A. Giuliani, S. Mereghetti, P. Caraveo, F. Perotti (INAF/IASF-Mi), I. Donnarumma (INAF/IASF-Rm), F. D'Ammando (INAF/IASF-Pa), E. Del Monte, Y. Evangelista, M. Feroci, F. Lazzarotto, L. Pacciani, P. Soffitta, E. Costa, I. Lapshov, M. Rapisarda, A. Argan, G. Piano, G. Pucella, S. Sabatini, A. Trois, V. Vittorini (INAF/IASF-Rm), F. Fuschino, M. Galli, C. Labanti, M. Marisaldi, G. Di Cocco (INAF/IASF-Bo), A. Pellizzoni, M. Pilia (INAF/OA-Cagliari), G. Barbiellini, F. Longo, E. Moretti, E. Vallazza (INFN Trieste), A. Morselli, P. Picozza (INFN and Univ. Roma Tor Vergata), M. Prest (Universita` dell'Insubria), P. Lipari, D. Zanello (INFN and Univ. Roma Sapienza), P.W. Cattaneo, A. Rappoldi (INFN Pavia), P. Santolamazza, P. Giommi (ASDC), L. Salotti (ASI)
on 30 Nov 2010; 20:12 UT
Password Certification: Marco Tavani (tavani@iasf-roma.inaf.it)

Subjects: Gamma Ray, >GeV, Transients

AGILE is detecting intense gamma-ray emission above 100 MeV from an unidentified source near the Galactic plane, AGL J1037-5708, of Galactic coordinates (l, b) = (285.5, 1.1) ± 0.5 deg (95% stat.) ± 0.1 deg (syst.). Integrating from 2010-11-27 21:18 UT to 2010-11-30 14:08 UT, a maximum likelihood analysis yields a detection at a significance level larger than 5 sigma, and a flux above 300 x 10E-8 ph/cm2/s (E > 100 MeV). We notice that the HMXRB source 4U 1036-56 is within the AGL J1037-5708 error box. This measurement was obtained with AGILE observing a large portion of the sky in spinning mode. Multifrequency observations of the AGL J1037-5708 error box are strongly encouraged.

 

Chandra follow-up observation of the Crab nebula after the high energy flare

ATel #3058; D. Horns (Institut für Experimentalphysik, Univ. Hamburg), A. Tennant (NASA/MSFC), C. Ferrigno (ISDC/Univ. Geneva), M.C. Weisskopf (NASA/MSFC), A. Neronov (ISDC/University of Geneva), M. Tavani, E. Costa (INAF-IASF Roma), P. Caraveo (INAF-IASF Milano)
on 30 Nov 2010; 19:20 UT
Password Certification: Dieter Horns (Dieter.Horns@mpi-hd.mpg.de)

Subjects: X-ray, Gamma Ray, Neutron Stars, Pulsars, Variables

Following the GeV flare detected by Agile and Fermi on 2010-09-19 (ATELS #2855 and #2861), a series of three Chandra ToO observations have been carried out on 2010-09-28 (ATel #2882), 2010-10-28 (ATel #2994). The last observation of this series was performed on 2010-11-28 between 10:57:53 and 12:58:59 (UT). The sequence of the three images reveals a successive brightening of the NW part of the X-ray ring during the last two months by about 15%. This type of brightening has been observed previously with Chandra (Hester et al. 2002). The knot-like features to the SE of the pulsar remain similar to the first ToO observation. We thank the CXC and its director, Harvey Tananbaum, for making this observation possible. The data are available in the Chandra public archive.

 

Decreasing gamma-ray emission from the blazar 3C 454.3

ATel #3049; E. Striani (Univ. Roma Tor Vergata and INFN Roma), S. Vercellone (INAF/IASF-Pa), M. Tavani (INAF/IASF-Rm), F. Lucarelli, C. Pittori (ASDC), A. Bulgarelli, F. Gianotti, M. Trifoglio (INAF/IASF-Bo), F. Verrecchia, P. Santolamazza (ASDC), I. Donnarumma, V. Vittorini, E. Del Monte, Y. Evangelista, M. Feroci, F. Lazzarotto, L. Pacciani, P. Soffitta, E. Costa, I. Lapshov, M. Rapisarda, A. Argan, G. Piano, G. Pucella, S. Sabatini, A. Trois (INAF/IASF-Rm), F. Fuschino, M. Galli, C. Labanti, M. Marisaldi, G. Di Cocco (INAF/IASF-Bo), A. Chen, A. Giuliani, S. Mereghetti, P. Caraveo, F. Perotti (INAF/IASF-Mi), A. Pellizzoni, M. Pilia (INAF/OA-Cagliari), G. Barbiellini, F. Longo, E. Vallazza (INFN Trieste), F. D'Ammando (INAF-IASF Palermo), E. Moretti (KTH Stockholm), A. Morselli, P. Picozza (INFN and Univ. Roma Tor Vergata), M. Prest (Universita` dell'Insubria), P. Lipari, D. Zanello (INFN and Univ. Roma Sapienza), P.W. Cattaneo, A. Rappoldi (INFN Pavia), P. Giommi,(ASDC), L. Salotti, G. Valentini (ASI)
on 22 Nov 2010; 17:48 UT
Password Certification: Marco Tavani (tavani@iasf-roma.inaf.it)

Subjects: AGN, Blazars, Quasars, Transients

Following the exceptional gamma-ray activity from the FSRQ 3C 454.3 (reported in the ATels #3034, #3043, and #3041), the source flux is currently decreasing, as monitored by the AGILE satellite. 3C 454.3 reached its peak emission approximately during the period Nov. 18-20, 2010. Integrating between MJD 55518.3 and MJD 55520.3, a maximum likelihood analysis gives an average flux F = (54.5 +/- 4.2) e-6 ph/cm2/sec (E > 100 MeV). The source showed significant flux variability. The gamma-ray flux decreased by a factor of about 2.5 during the last 36 hours. An integration between 2010-11-21 04:50 UT and 2010-11-22 04:50 UT yields a flux F = (20.4 +/- 3.7) e-6 ph/cm2/sec (E > 100 MeV). Follow-up observations of 3C 454.3 are strongly encouraged.

 

AGILE detection of the extraordinary and prolonged gamma-ray activity from 3C 454.3

ATel #3043; E. Striani (Univ. Roma Tor Vergata and INFN Roma), S. Vercellone (INAF/IASF-Pa), F. Lucarelli, C. Pittori (ASDC), Tavani (INAF/IASF-Rm), A. Bulgarelli, F. Gianotti, M. Trifoglio (INAF/IASF-Bo), F. Verrecchia, P. Santolamazza (ASDC), I. Donnarumma, V. Vittorini, E. Del Monte, Y. Evangelista, M. Feroci, F. Lazzarotto, L. Pacciani, P. Soffitta, E. Costa, I. Lapshov, M. Rapisarda, A. Argan, G. Piano, G. Pucella, S. Sabatini, A. Trois (INAF/IASF-Rm), F. Fuschino, M. Galli, C. Labanti, M. Marisaldi, G. Di Cocco (INAF/IASF-Bo), A. Chen, A. Giuliani, S. Mereghetti, P. Caraveo, F. Perotti (INAF/IASF-Mi), A. Pellizzoni, M. Pilia (INAF/OA-Cagliari), G. Barbiellini, F. Longo, E. Vallazza (INFN Trieste), F. D'Ammando (INAF-IASF Palermo), E. Moretti (KTH Stockholm), A. Morselli, P. Picozza (INFN and Univ. Roma Tor Vergata), M. Prest (Universita` dell'Insubria), P. Lipari, D. Zanello (INFN and Univ. Roma Sapienza), P.W. Cattaneo, A. Rappoldi (INFN Pavia), P. Giommi,(ASDC), L. Salotti, G. Valentini (ASI)
on 19 Nov 2010; 16:49 UT
Password Certification: Marco Tavani (tavani@iasf-roma.inaf.it)

Subjects: Gamma Ray, >GeV, Request for Observations, AGN, Blazars, Quasars, Transients
Referred to by ATel #: 3047

Following the detection by AGILE (ATel #3034) and Fermi-LAT (ATel #3041) of the dramatic gamma-ray flare from the Flat Spectrum Radio Quasar 3C 454.3 between November 16 and November 18, 2010, we report on its prolonged gamma-ray activity detected by AGILE. For a 30-hour integration, from 2010-11-18 03:15 UT to 2010-11-19 09:15 UT, a preliminary quicklook maximum likelihood analysis of the AGILE-GRID data yields an average flux F = (58 +/- 6)e-6 ph/cm2/sec (E > 100 MeV), i.e., approximately the same peak flux reported by Fermi-LAT on a 18-hour time scale (from 2011-11-16 12:00 UT to 2011-11-17 06:00 UT,ATel #3041). Follow-up observations of 3C 454.3 are strongly encouraged.

 

AGILE detects another extraordinary gamma-ray flare from the blazar 3C 454.3

ATel #3034; E. Striani (Univ. Roma Tor Vergata and INFN Roma), F. Lucarelli (ASDC), S. Vercellone (INAF/IASF-Pa), A. Bulgarelli, F. Gianotti, M. Trifoglio (INAF/IASF-Bo), Tavani (INAF/IASF-Rm), C. Pittori, F. Verrecchia, P. Santolamazza (ASDC), I. Donnarumma, V. Vittorini, E. Del Monte, Y. Evangelista, M. Feroci, F. Lazzarotto, L. Pacciani, P. Soffitta, E. Costa, I. Lapshov, M. Rapisarda, A. Argan, G. Piano, G. Pucella, S. Sabatini, A. Trois (INAF/IASF-Rm), F. Fuschino, M. Galli, C. Labanti, M. Marisaldi, G. Di Cocco (INAF/IASF-Bo), A. Chen, A. Giuliani, S. Mereghetti, P. Caraveo, F. Perotti (INAF/IASF-Mi), A. Pellizzoni, M. Pilia (INAF/OA-Cagliari), G. Barbiellini, F. Longo, E. Vallazza (INFN Trieste), E. Moretti (KTH Stockholm), A. Morselli, P. Picozza (INFN and Univ. Roma Tor Vergata), M. Prest (Universita` dell'Insubria), P. Lipari, D. Zanello (INFN and Univ. Roma Sapienza), P.W. Cattaneo, A. Rappoldi (INFN Pavia), P. Giommi,(ASDC), L. Salotti, G. Valentini (ASI)
on 17 Nov 2010; 14:40 UT
Password Certification: Marco Tavani (tavani@iasf-roma.inaf.it)

Subjects: Request for Observations, AGN, Blazars, Quasars, Transients
Referred to by ATel #: 3036, 3041, 3043, 3047

The AGILE Gamma-Ray Imaging Detector (GRID) is now detecting a very intense gamma-ray flare above 100 MeV from the Flat Spectrum Radio Quasar 3C 454.3. Integrating from 2010-11-16 6:50 UT to 2010-11-17 09:15 UT, a preliminary quicklook maximum likelihood analysis yields a source flux of F = (2600 +/- 400)e-8 ph/cm2/sec (E > 100 MeV), which represents an increase by a factor of ~ 4 in 24 hours. Since the end of October, 2010, 3C454.3 has been detected in a high state in the NIR, optical and gamma-ray energy bands (ATel #2988, ATel #2995, ATel #3003, ATel #3005, ATel #3022). This detection was obtained while AGILE is observing in spinning mode, surveying a large fraction of the sky each day. Multifrequency observations of 3C 454.3 are strongly encouraged.

 

AGILE detects gamma-ray emission from AGL J2330-5036, in the region of BZQ J2329-4955 (PKS 2326-502)

ATel #3008; F. Lucarelli, F. Verrecchia (ASDC), E. Striani (Univ. Roma Tor Vergata and INFN Roma), C. Pittori (ASDC), M. Tavani (INAF/IASF-Rm, and Univ. Tor Vergata), S. Vercellone (INAF/IASF-Pa), A. Bulgarelli, F. Gianotti, M. Trifoglio (INAF/IASF-Bo), A. Chen, A. Giuliani, S. Mereghetti, P. Caraveo, F. Perotti (INAF/IASF-Mi), I. Donnarumma (INAF/IASF-Rm), F. D'Ammando (INAF/IASF-Pa), E. Del Monte, Y. Evangelista, M. Feroci, F. Lazzarotto, L. Pacciani, P. Soffitta, E. Costa, I. Lapshov, M. Rapisarda, A. Argan, G. Piano, G. Pucella, S. Sabatini, A. Trois, V. Vittorini (INAF/IASF-Rm), F. Fuschino, M. Galli, C. Labanti, M. Marisaldi, G. Di Cocco (INAF/IASF-Bo), A. Pellizzoni, M. Pilia (INAF/OA-Cagliari), G. Barbiellini, F. Longo, E. Vallazza (INFN Trieste), A. Morselli, P. Picozza (INFN and Univ. Roma Tor Vergata), M. Prest (Universita` dell'Insubria), P. Lipari, D. Zanello (INFN and Univ. Roma Sapienza), P.W. Cattaneo, A. Rappoldi (INFN Pavia), P. Santolamazza, S. Colafrancesco, P. Giommi (ASDC), L. Salotti (ASI)
on 5 Nov 2010; 17:14 UT
Password Certification: Fabrizio Lucarelli (fabrizio.lucarelli@asdc.asi.it)

Subjects: Gamma Ray, >GeV, AGN, Blazars, Transients

AGILE is detecting intense gamma-ray emission from the source AGL J2330-5036, at the position (R.A., Dec.) = (352.55, -50.60) deg (J2000); (l, b) = (330.82, -61.90) +/- 0.8 deg (95% stat.) +/- 0.1 deg (syst.), consistent within the error circle with the flat-spectrum radio quasar BZQ J2329-4955 (PKS 2326-502). Integrating from 2010-11-01 00:00 UT to 2010-11-05 03:00 UT, a maximum likelihood analysis yields a detection at a significance level above 5 sigma and a flux of (220 +/- 70) x 10^-8 ph/cm2/s (E > 100 MeV). A shorter integration, starting from 2010-11-03 00:00 UT to 2010-11-05 04:00 UT, yields a detection at a significance level around 5 sigma and a flux of (300 +/- 100) x 10^-8 ph/cm2/s (E > 100 MeV). This source is positionally consistent with the First Fermi-LAT Catalogue source 1FGL J2329.2-4954 (Abdo et al. 2010, ApJS, 188, 405) and with the source reported in the ATel #2783. This measurement was obtained with AGILE observing a large portion of the sky in a spinning mode. Multifrequency observations of the AGL J2330-5036 error box are strongly encouraged.

 

AGILE/GRID detection of increased gamma-ray emission from 3C 454.3

ATel #2995; S. Vercellone (INAF/IASF-Pa), F. Verrecchia (ASDC), I. Donnarumma (INAF/IASF-Rm), M. Tavani (INAF/IASF-Rm, and Univ. Tor Vergata), E. Striani (Univ. Roma Tor Vergata and INFN Roma), F. Lucarelli, C. Pittori (ASDC), A. Bulgarelli, F. Gianotti, M. Trifoglio (INAF/IASF-Bo), F. D'Ammando (INAF/IASF-Pa), A. Chen, A. Giuliani, S. Mereghetti, P. Caraveo, F. Perotti (INAF/IASF-Mi), E. Del Monte, Y. Evangelista, M. Feroci, F. Lazzarotto, L. Pacciani, P. Soffitta, E. Costa, I. Lapshov, M. Rapisarda, A. Argan, G. Piano, G. Pucella, S. Sabatini, A. Trois, V. Vittorini (INAF/IASF-Rm), F. Fuschino, M. Galli, C. Labanti, M. Marisaldi, G. Di Cocco (INAF/IASF-Bo), A. Pellizzoni, M. Pilia (INAF/OA-Cagliari), G. Barbiellini, F. Longo, E. Vallazza (INFN Trieste), A. Morselli, P. Picozza (INFN and Univ. Roma Tor Vergata), M. Prest (Universita` dell'Insubria), P. Lipari, D. Zanello (INFN and Univ. Roma Sapienza), P.W. Cattaneo, A. Rappoldi (INFN Pavia), P. Santolamazza, S. Colafrancesco, P. Giommi (ASDC), L. Salotti (ASI)
on 1 Nov 2010; 11:47 UT
Password Certification: Stefano Vercellone (stefano@iasf-milano.inaf.it)

Subjects: Gamma Ray, >GeV, AGN, Blazars, Quasars

Following the detection of a NIR H-band flare from the flat spectrum radio quasar 3C 454.3 reported in ATel #2988, we performed a quick-look analysis of the gamma-ray data collected by the Gamma-ray Imaging Detector (GRID) on board AGILE in the time period between 2010-10-28 06:00 UT and 2010-10-31 06:00 UT. Although the source is considerably off-axis, we detect 3C 454.3 in a high gamma-ray state. The gamma-ray flux is (730+-230)E-8 ph/cm2/s (E>100 MeV). This flux value reported here is more than a factor 2 higher than the flux we detected during the last two weeks of July 2010. The AGILE/GRID detection was obtained while AGILE is observing in spinning mode, surveying a large fraction of the sky each day. Multifrequency observations of 3C 454.3 are strongly encouraged.

 

Chandra follow-up observation of the Crab nebula after the very high energy flare

ATel #2994; C. Ferrigno (ISDC/University of Geneva), A. Tennant (NASA/MSFC), D. Horns (Institut für Experimentalphysik, Univ. Hamburg) , M.C. Weisskopf (NASA/MSFC), A. Neronov (ISDC/University of Geneva), M. Tavani, E. Costa (INAF-IASF Roma), and P. Caraveo (INAF-IASF Milano)
on 1 Nov 2010; 11:40 UT
Password Certification: Carlo Ferrigno (Carlo.Ferrigno@unige.ch)

Subjects: X-ray, Pulsars, Supernova Remnants
Referred to by ATel #: 3058

A Chandra TOO observation of the inner part of the Crab nebula has been performed on 2010 Oct 28 from 17:40 and 19:41 UT to monitor the evolution of the small scale structures in the region of the inner ring after the GeV flare detected by AGILE and FERMI on 2010-09-19 (ATels #2855 and #2861). During a previous observation, performed on 2010-09-28 from 05:05 to 07:01 UT (ATel #2882), a series of three bright knots were noticed on the inner ring, at about 6 arcsec SE of the pulsar, in the region of apparent intersectionwith the jet. The brightening of these knots could be connected to the previous GeV flare. In the current observation, the three structures are still present and have the same intensity within the statistical uncertainties with respect to the previous observation: 3 sigma upper limits on the variability are ~8% withoutbackground subtraction and pile-up corrections. Also the other nebular structures remained substantially unchanged. A third Chandra monitoring observation of the Crab nebula is scheduled on 2010-11-26. We thank the CXC and its director, Harvey Tananbaum, for making this observation possible. The data are available in the Chandra public archive.

 

AGILE detection of AGL J0813+2420, a new unidentified gamma-ray source

ATel #2971; F. Lucarelli, F. Verrecchia (ASDC), E. Striani (Univ. Roma Tor Vergata and INFN Roma), S. Vercellone (INAF/IASF-Pa), C. Pittori (ASDC), M. Tavani (INAF/IASF-Rm, and Univ. Tor Vergata), A. Bulgarelli, F. Gianotti, M. Trifoglio (INAF/IASF-Bo), A. Chen, A. Giuliani, S. Mereghetti, P. Caraveo, F. Perotti (INAF/IASF-Mi), I. Donnarumma (INAF/IASF-Rm), F. D'Ammando (INAF/IASF-Pa), E. Del Monte, Y. Evangelista, M. Feroci, F. Lazzarotto, L. Pacciani, P. Soffitta, E. Costa, I. Lapshov, M. Rapisarda, A. Argan, G. Piano, G. Pucella, S. Sabatini, A. Trois, V. Vittorini (INAF/IASF-Rm), F. Fuschino, M. Galli, C. Labanti, M. Marisaldi, G. Di Cocco (INAF/IASF-Bo), A. Pellizzoni, M. Pilia (INAF/OA-Cagliari), G. Barbiellini, F. Longo, E. Vallazza (INFN Trieste), A. Morselli, P. Picozza (INFN and Univ. Roma Tor Vergata), M. Prest (Universita` dell'Insubria), P. Lipari, D. Zanello (INFN and Univ. Roma Sapienza), P.W. Cattaneo, A. Rappoldi (INFN Pavia), P. Santolamazza, S. Colafrancesco, P. Giommi (ASDC), L. Salotti (ASI)
on 26 Oct 2010; 14:24 UT
Password Certification: Fabrizio Lucarelli (fabrizio.lucarelli@asdc.asi.it)

Subjects: Gamma Ray, >GeV, Request for Observations, Transients

AGILE is detecting intense gamma-ray emission above 100 MeV from a new unidentified source, AGL J0813+2420, with Galactic coordinates (l, b) = (198.4, 28.1) +/- 0.5 deg (95% stat.) +/- 0.1 deg (syst.) (R.A.: 123.4, Dec.: 24.6, J2000). Integrating from 2010-10-23 18:00 UT to 2010-10-26 06:00 UT, a maximum likelihood analysis yields a detection at a significance level above 5 sigma, and a flux of (260 +/- 80) x 10^-8 ph/cm2/s (E > 100 MeV). No prominent extragalactic or Galactic gamma-ray source are known within the AGL J0813+2420 error circle. The source position is consistent with the flat spectrum radio source CRATES J0813+2435, which is about at 16 arcminutes from the emission peak. This measurement was obtained with AGILE observing a large portion of the sky in a spinning mode. Multifrequency observations of the AGL J0813+2420 error circle are strongly encouraged.

 

AGILE detection of prolonged gamma-ray activity from the blazar PKS 1830-211

ATel #2950; I. Donnarumma (INAF/IASF-Rm), S. Vercellone (INAF/IASF-Pa), M. Tavani (INAF/IASF-Rm, and Univ. Tor Vergata), C. Pittori, F. Lucarelli, F. Verrecchia (ASDC), A. Chen (INAF/IASF-Mi), A. Bulgarelli, F. Gianotti, M. Trifoglio (INAF/IASF-Bo), A. Giuliani, S. Mereghetti, P. Caraveo, F. Perotti (INAF/IASF-Mi), F. D'Ammando (INAF/IASF-Pa), E. Del Monte, Y. Evangelista, M. Feroci, F. Lazzarotto, L. Pacciani, P. Soffitta, E. Costa, I. Lapshov, M. Rapisarda, A. Argan, G. Piano, G. Pucella, S. Sabatini, A. Trois, V. Vittorini (INAF/IASF-Rm), F. Fuschino, M. Galli, C. Labanti, M. Marisaldi, G. Di Cocco (INAF/IASF-Bo), A. Pellizzoni, M. Pilia (INAF/OA-Cagliari), G. Barbiellini, F. Longo, E. Moretti, E. Vallazza (INFN Trieste), A. Morselli, P. Picozza, E. Striani (INFN and Univ. Roma Tor Vergata), M. Prest (Universita` dell'Insubria), P. Lipari, D. Zanello (INFN and Univ. Roma Sapienza), P.W. Cattaneo, A. Rappoldi (INFN Pavia), P. Santolamazza, S. Colafrancesco, P. Giommi (ASDC), L. Salotti (ASI)
on 17 Oct 2010; 18:59 UT
Password Certification: Donnarumma Immacolata (immacolata.donnarumma@iasf-roma.inaf.it)

Subjects: Gamma Ray, >GeV, Request for Observations, AGN, Blazars, Quasars

The AGILE Gamma-Ray Imaging Detector (GRID) has been detecting prolonged gamma-ray emission above 100 MeV from a source at (l,b)=(12.17,-6.25) [RA(J2000)=18h 35m 44.07s, DEC(J2000)=-21h 18m 00.7s] positionally consistent with the high z blazar (z=2.507) PKS 1830-211. Integrating from 2010-10-15 00:00UT to 2010-10-17 00:00UT, a quick-look maximum likelihood analysis yields a source flux of about (5.7+-1.8)E-6 ph/cm2/sec (E > 100 MeV). This flux value is, within the statistical errors, comparable to the daily flux value detected by Fermi/LAT on 2010-10-14, and reported in ATel #2943. It is worth noting that an enhancement in the gamma-ray activity of this blazar was detected by AGILE on 2009-10-12 (see ATel #2242), when it was detected at a flux level about 3.5 times lower than the current one. The AGILE-GRID detection was obtained while AGILE is observing in spinning mode, surveying a large fraction of the sky each day. Multi-frequency observations of PKS 1830-211 are strongly encouraged.

 

HST observation of the Crab Nebula following the September 2010 gamma-ray flare

ATel #2903; P.Caraveo (IASF/INAF Milano), A. De Luca (IUSS, Pavia), R. Mignani (Mssl, UK), D. Salvetti (IASF/INAF Milano), G.F. Bignami (IUSS, Pavia), M. Tavani (IASF/INAF Roma), E. Costa (IASF/INAF Roma), A. Pellizzoni (IASF/INAF Cagliari) on behalf of the AGILE TEAM, R. Buehler (SLAC/KIPAC), F. D'Ammando (INAF-IASF Palermo), E. Hays (NASA/GSFC) on behalf of the Fermi Large Area Telescope Collaboration, A. Tennant (NASA/MSFC), M.C. Weisskopf (NASA/MSFC), D. Horns (Univ. Hamburg)
on 4 Oct 2010; 11:42 UT
Password Certification: Andrea De Luca (deluca@iasf-milano.inaf.it)

Subjects: Optical, Neutron Stars, Pulsars

Following the discovery by AGILE (ATel #2855) and the confirmation by Fermi/LAT (ATel #2861) of enhanced gamma-ray emission from the Crab Nebula region in the time interval from Sept.18 to Sept.22, 2010, we have been granted a Hubble Space Telescope observation in the frame of the Director Discretionary time (program 12381). The observation, 2000 sec. long, centered on the Crab pulsar was performed by the ACS instrument (field of view 200 x 200 arcsec) equipped with filter F550M on Oct.2nd, 02:44 UT. (A previous attempt on Sept 29 failed,owing to a star acquisition problem). Comparing the current Crab Nebula image with the extensive database available in the HST public archive, we notice an increased emission about 3 arcsec East of the pulsar. A Chandra exposure, taken a few days before the HST one, reported a brightening from the same region (ATel #2882). Also, the wisps north-west of the pulsar appear bright, with a remarkable sinuous feature between Wisp 1A and Wisp 2, as named in Hester et al. 1995 (ApJ, 448, 240). We thank the HST director for the effort done to perform this DD observation. The data are available in the HST public archive.

HST/ACS image of the Crab (2010 Oct. 2)

 

Chandra observation of the Crab Nebula/PSR following the September 2010 gamma-ray flare.

ATel #2882; A. Tennant (NASA/MSFC), P. Caraveo (INAF-IASF Milano), E. Costa (INAF-IASF Roma), Y. Evangelista (INAF-IASF Roma), C. Ferrigno (ISDC Data Centre for Astrophysics, University of Geneva ), C. Heinke (U. of Alberta, Canada), D. Horns (Institut für Experimentalphysik, Univ. Hamburg) A. Pellizzoni (INAF-Osserv. Cagliari), M. Tavani (INAF-IASF Roma), M.C. Weisskopf (NASA/MSFC).
on 28 Sep 2010; 20:16 UT
Password Certification: Martin C.Weisskopf (martin.c.weisskopf@nasa.gov)

Subjects: X-ray, Neutron Stars, Pulsars, Supernova Remnants

Following the detection by AGILE (ATel #2855) of enhanced gamma-ray emission from a source positionally consistent with the Crab Nebula, and subsequently confirmed by Fermi/LAT (ATel #2861), we requested and performed a ToO Chandra/ACIS-S3 observation (ObsID 13139). We observed for 5ks using a custom window and a 0.2s frame time. Under these conditions, all of the Nebula, except the 2 arc-second region surrounding the pulsar, is observed with Chandra resolution. The pulsar itself is missing from the image due to the high degree of pileup. We see nothing especially unusual in this image when compared to the over 35 previous Chandra images that show the Nebula in sufficient detail. It is worth noting that the enhancement, or bright knot, of the “jet” about 6-arcseconds south-east of the pulsar, now appears to extend down to about 3 arcsec from the pulsar. A similar extension was seen in Chandra ObsId 2001 (2001-Jan-31). However, the statistics of these two observations limit our ability to make detailed comparisons. To the extent that this feature is new, or that it has been observed before, it is unclear if it is related to the gamma-ray event. We also note, although not related to the gamma-ray flare, that the large-scale structure of the X-ray jet to the south-east (scales of an arc-minute or more) has changed significantly from what it was several years ago. The jet clearly exhibits the same "firehose-instability-like" structure as seen in Vela. We thank the CXC and its director, Harvey Tananbaum, for making this observation possible and on on such short notice. The data are available in the Chandra public archive.

 

AGILE upper limits above 100 MeV regarding the recent transient MAXI J1659-152

ATel #2880; F. Lucarelli, F. Verrecchia (ASDC), A. Chen (INAF/IASF-Mi), M. Tavani (INAF/IASF-Rm, and Univ. Tor Vergata), C. Pittori (ASDC), A. Bulgarelli, F. Gianotti, M. Trifoglio (INAF/IASF-Bo), A. Giuliani, S. Mereghetti, P. Caraveo, F. Perotti (INAF/IASF-Mi), I. Donnarumma (INAF/IASF-Rm), F. D'Ammando, S. Vercellone (INAF/IASF-Pa), E. Del Monte, Y. Evangelista, M. Feroci, F. Lazzarotto, L. Pacciani, P. Soffitta, E. Costa, I. Lapshov, M. Rapisarda, A. Argan, G. Piano, G. Pucella, S. Sabatini, A. Trois, V. Vittorini (INAF/IASF-Rm), F. Fuschino, M. Galli, C. Labanti, M. Marisaldi, G. Di Cocco (INAF/IASF-Bo), A. Pellizzoni, M. Pilia (INAF/OA-Cagliari), G. Barbiellini, F. Longo, E. Moretti, E. Vallazza (INFN Trieste), A. Morselli, P. Picozza, E. Striani (INFN and Univ. Roma Tor Vergata), M. Prest (Universita` dell'Insubria), P. Lipari, D. Zanello (INFN and Univ. Roma Sapienza), P.W. Cattaneo, A. Rappoldi (INFN Pavia), P. Santolamazza, S. Colafrancesco, P. Giommi (ASDC), L. Salotti (ASI)
on 28 Sep 2010; 16:34 UT
Password Certification: Fabrizio Lucarelli (fabrizio.lucarelli@asdc.asi.it)

Subjects: Gamma Ray, >GeV, Transients
Referred to by ATel #: 2881

Following the detection of the new hard X-ray transient by MAXI/GSC (ATel #2873) confirmed by INTEGRAL (ATel #2875) and in the radio band by WSRT (ATel #2874), we searched for significant excess in the AGILE data at the MAXI source position (R.A., Dec = +254.79 deg, -15.27 deg, J2000). Integrating from 2010-09-25 00:00 UT to 2010-09-26 14:00 UT, a maximum likelihood analysis yields a 95 % C.L. upper limit of 80 e-8 ph/cm2/s (E > 100 MeV). No significant detection is obtained for a longer 7-day integration, from 2010-09-20 00:00 UT to 2010-09-27 00:00 UT, yielding a 95 % C.L. upper limit of 40 e-8 ph/cm2/s (E > 100 MeV). AGILE will continue to monitor the MAXI transient region. This measurement was obtained with AGILE observing a large portion of the sky in spinning mode.

 

Swift/XRT observation of the Crab Nebula/PSR following the September 2010 gamma-ray flare

ATel #2866; Y. Evangelista, R. Campana (INAF/IASF Roma), M. Capalbi (ASDC), V. Mangano (IASF-Pa), E. Costa, I. Donnarumma, M. Feroci, L. Pacciani, E. Del Monte, F. Lazzarotto, P. Soffitta, I. Lapshov, M. Tavani (INAF/IASF Roma), E. Striani (Univ. Tor Vergata), C. Pittori, F. Verrecchia (ASDC), P. Romano (IASF-Pa), A. Bulgarelli (INAF/IASF Bologna), F. Gianotti, M. Trifoglio (INAF/IASF Bologna), A. Argan, A. Trois, G. De Paris, V. Vittorini, S. Sabatini, G. Piano (INAF/IASF Roma), F. D'Ammando (IASF-Pa), A. Chen, A. Giuliani(INAF-IASF-Milano), M. Marisaldi, G. Di Cocco, C. Labanti, F. Fuschino,M. Galli (INAF/IASF Bologna), P. Caraveo, S. Mereghetti, F. Perotti (INAF/IASF Milano), G. Pucella, M. Rapisarda (ENEA-Roma), S. Vercellone (IASF-Pa), A. Pellizzoni, M. Pilia (INAF/OA-Cagliari), G. Barbiellini, F. Longo (INFN Trieste), P. Picozza, A. Morselli (INFN and Univ. Tor Vergata), M. Prest (Universita` dell'Insubria), P. Lipari, D. Zanello (INFN Roma-1), P.W. Cattaneo, A. Rappoldi (INFN Pavia), P. Giommi, P. Santolamazza, F. Lucarelli (ASDC), L. Salotti (ASI)
on 24 Sep 2010; 14:26 UT
Password Certification: Yuri Evangelista (yuri.evangelista@iasf-roma.inaf.it)

Subjects: X-ray, Gamma Ray, >GeV, Neutron Stars, Pulsars, Supernova Remnants
Referred to by ATel #: 2867, 2868, 2872

Following the detection by AGILE (ATel #2855) of enhanced gamma-ray emission from a source positionally consistent with the Crab Nebula, confirmed also by Fermi/LAT (ATel #2861), we requested a ToO Swift/XRT observation. We obtained 1 ks XRT observation of the Crab Nebula in the windowed timing (WT) mode starting at 2010-09-22 16:42:44 UT. A preliminary analysis does not reveal any significant change in the source flux and spectrum compared with previously detected values (see, e.g., Weisskopf et al., ApJ, 713, 2010 and references therein). We also analyzed the source pulse profile. From a comparison with the XRT folded light-curve reported in Cusumano et al., Proceedings of the SPIE, 5898, (2005) we do not detect any significant change in the X-ray pulse shape. Analysis of additional Swift observations of the Crab Nebula/PSR is in progress. We thank the Swift team for the prompt scheduling of this observation.

 

AGILE detection of enhanced gamma-ray emission from the Crab Nebula region

ATel #2855; M. Tavani (INAF/IASF Roma), E. Striani (Univ. Tor Vergata), A. Bulgarelli (INAF/IASF Bologna), F. Gianotti, M. Trifoglio (INAF/IASF Bologna), C. Pittori, F. Verrecchia (ASDC), A. Argan, A. Trois, G. De Paris, V. Vittorini, F. D'Ammando, S. Sabatini, G. Piano, E. Costa, I. Donnarumma, M. Feroci, L. Pacciani, E. Del Monte, F. Lazzarotto, P. Soffitta, Y. Evangelista, I. Lapshov (INAF-IASF-Rm), A. Chen, A. Giuliani(INAF-IASF-Milano), M. Marisaldi, G. Di Cocco, C. Labanti, F. Fuschino,M. Galli (INAF/IASF Bologna), P. Caraveo, S. Mereghetti, F. Perotti (INAF/IASF Milano), G. Pucella, M. Rapisarda (ENEA-Roma), S. Vercellone (IASF-Pa), A. Pellizzoni, M. Pilia (INAF/OA-Cagliari), G. Barbiellini, F. Longo (INFN Trieste), P. Picozza, A. Morselli (INFN and Univ. Tor Vergata), M. Prest (Universita` dell'Insubria), P. Lipari, D. Zanello (INFN Roma-1), P.W. Cattaneo, A. Rappoldi (INFN Pavia), P. Giommi, P. Santolamazza, F. Lucarelli, S. Colafrancesco (ASDC), L. Salotti (ASI)
on 22 Sep 2010; 14:45 UT
Distributed as an Instant Email Notice (Transients)
Password Certification: Marco Tavani (tavani@iasf-roma.inaf.it)

Subjects: Pulsars
Referred to by ATel #: 2856, 2858, 2861

AGILE is detecting an increased gamma-ray flux from a source positionally consistent with the Crab Nebula. Integrating during the period 2010-09-19 00:10 UT to 2010-09-21 00:10 UT the AGILE-GRID detected enhanced gamma-ray emission above 100 MeV from a source at Galactic coordinates (l,b) = (184.6, -6.0) +/- 0.4 (stat.) +/- 0.1 (syst.) deg, and flux F > 500 e-8 ph/cm2/sec above 100 MeV, corresponding to an excess with significance above 4.4 sigma with respect to the average flux from the Crab nebula (F = (220 +/- 15)e-8 ph/cm^2/sec, Pittori et al., 2009, A&A, 506, 1563). We strongly encourage multifrequency observations of the Crab Nebula region.

 

AGILE detection of transient gamma-ray emission from the PSR B1259-63 region

ATel #2772; M. Tavani (INAF-IASF-Rm and Univ. Tor Vergata), F. Lucarelli, C. Pittori, F. Verrecchia (ASDC), A. Bulgarelli, F. Gianotti, M. Trifoglio (INAF/IASF Bologna), E. Striani (Univ. Tor Vergata), S. Sabatini, G. Piano (INAF/IASF Roma), A. Argan, A. Trois, G. De Paris, V. Vittorini, E. Costa, I.Donnarumma, M. Feroci, L. Pacciani, E. Del Monte, F. Lazzarotto, P. Soffitta, Y. Evangelista, I. Lapshov (INAF-IASF-Rm), A. Chen, A. Giuliani (INAF-IASF-Milano), M. Marisaldi, G. Di Cocco, C. Labanti, F. Fuschino, M. Galli (INAF/IASF Bologna), P. Caraveo, S. Mereghetti, F. Perotti (INAF/IASF Milano), G. Pucella, M. Rapisarda (ENEA-Roma), A. Pellizzoni, M. Pilia (INAF/OA-Cagliari), G. Barbiellini, F. Longo (INFN Trieste), P. Picozza, A. Morselli (INFN and Univ. Tor Vergata), M. Prest (Universita` dell'Insubria), P. Lipari, D. Zanello (INFN Roma-1), S. Vercellone, F.D'Ammando (INAF/IASF-Palermo), P.W. Cattaneo, A. Rappoldi (INFN Pavia), P. Giommi, P. Santolamazza (ASDC), S. Colafrancesco and L. Salotti (ASI)
on 5 Aug 2010; 13:04 UT
Distributed as an Instant Email Notice (Request for Observations)
Password Certification: Carlotta Pittori (carlotta.pittori@asdc.asi.it)

Subjects: Gamma Ray, >GeV, Request for Observations, Binaries, Pulsars, Transients
Referred to by ATel #: 2780, 2782

AGILE is detecting transient gamma-ray emission above 100 MeV from a source near the Galactic plane and positionally consistent with the binary pulsar PSR B1259-63 (J2000 coordinates: RA: 13 02 47.66, Dec: -63 50 08.6; l = 304.1836, b = -0.9916). Integrating from 2010-08-02 06:40 UT to 2010-08-04 04:00 UT, a preliminary maximum likelihood analysis yields a detection centered at Galactic coordinates (l,b) = (304.7,-0.8) ± 0.6 (stat.) ± 0.1 (syst.) (RA=196.9,Dec=-63.7 J2000), with a significance level of about 4.5 sigma, and a gamma-ray flux above 2 x 10E-6 ph/cm2/sec for photon energies above 100 MeV. An independent analysis based on the false discovery rate (FDR) method gives a probability of less than 0.001 for the signal to be consistent with the null hypothesis. We note that this transient gamma-ray source is positionally consistent with the pulsar binary system PSR B1259-63 made of a 49.96 sec radio pulsar orbiting around a Be star companion in a highly elliptical orbit (of period P = 3.38 yrs). The pulsar is now in the approaching-to-periastron part of the orbit, and is expected to reach the region close to periastron in mid-December 2010. Time variable high-energy emission (ATel #249, M. Beilicke et al.) can be produced by the interaction of the relativistic pulsar wind with the gaseous outflow from the Be star companion (e.g., Tavani & Arons, 1997, ApJ, 499, 439). Multifrequency observations of the PSR B1259-63 region are strongly encouraged as well as monitoring of the binary pulsar system.

 

AGILE detection of the new unidentified gamma-ray source AGL J2241+4454

ATel #2761; F. Lucarelli, F. Verrecchia (ASDC), E. Striani (Univ. Roma Tor Vergata and INFN Roma), C. Pittori (ASDC), M. Tavani (INAF/IASF-Rm, and Univ. Tor Vergata), S. Vercellone (INAF/IASF-Pa), A. Bulgarelli, F. Gianotti, M. Trifoglio (INAF/IASF-Bo), A. Chen, A. Giuliani, S. Mereghetti, P. Caraveo, F. Perotti (INAF/IASF-Mi), I. Donnarumma (INAF/IASF-Rm), F. D'Ammando (INAF/IASF-Pa), E. Del Monte, Y. Evangelista, M. Feroci, F. Lazzarotto, L. Pacciani, P. Soffitta, E. Costa, I. Lapshov, M. Rapisarda, A. Argan, G. Piano, G. Pucella, S. Sabatini, A. Trois, V. Vittorini (INAF/IASF-Rm), F. Fuschino, M. Galli, C. Labanti, M. Marisaldi, G. Di Cocco (INAF/IASF-Bo), A. Pellizzoni, M. Pilia (INAF/OA-Cagliari), G. Barbiellini, F. Longo, E. Moretti, E. Vallazza (INFN Trieste), A. Morselli, P. Picozza (INFN and Univ. Roma Tor Vergata), M. Prest (Universita` dell'Insubria), P. Lipari, D. Zanello (INFN and Univ. Roma Sapienza), P.W. Cattaneo, A. Rappoldi (INFN Pavia), P. Santolamazza, S. Colafrancesco, P. Giommi (ASDC), L. Salotti (ASI)
on 27 Jul 2010; 17:21 UT
Distributed as an Instant Email Notice (Request for Observations)
Password Certification: Fabrizio Lucarelli (fabrizio.lucarelli@asdc.asi.it)

Subjects: Gamma Ray, >GeV, Request for Observations, Transients

AGILE is detecting intense gamma-ray emission above 100 MeV from a new unidentified source, AGL J2241+4454, with Galactic coordinates (l, b) = (100.0, -12.2) ± 0.6 deg (95% stat.) ± 0.1 deg (syst.) (R.A.=340.3, Dec.=44.9, J2000). Integrating from 2010-07-25 01:00 UT to 2010-07-26 23:30 UT, a maximum likelihood analysis yields a detection at a significance level larger than 5 sigma, and a flux above 150 x 10E-8 ph/cm2/s (E > 100 MeV). No prominent extragalactic or Galactic sources are known within the AGL J2241+4454 error circle. This measurement was obtained with AGILE observing a large portion of the sky in spinning mode. Multifrequency observations of the AGL J2241+4454 error circle are strongly encouraged.

 

Swift/XRT observations of Cyg X-1 during state transition

ATel #2724; Evangelista, Y.; Campana, R.; Del Monte, E.; Sabatini, S. (INAF/IASF-Rm); Striani, E. (Univ. Roma Tor Vergata and INFN Roma); Campana, S. (INAF-OAB); Costa, E.; Donnarumma, I.; Feroci, M.; Lazzarotto, F.; Pacciani, L.; Soffitta, P.; Lapshov, I.; Tavani, M.; Vittorini, V.; Argan, A.; Trois, A.; Piano, G. (INAF/IASF-Rm); Rapisarda, M. (ENEA Frascati); Giuliani, A.; Chen, A.; Mereghetti, S.; Perotti, F.; Caraveo, P. (INAF/IASF Mi); Pellizzoni, A.; Pilia, M. (INAF/OA-Cagliari); D'Ammando, F.; Vercellone, S. (INAF/IASF Pa); Bulgarelli, A.; Gianotti, F.; Trifoglio, M.; Di Cocco, G.; Labanti, C.; Fuschino, F.; Marisaldi, M.; Galli, M. (INAF/IASF Bo); Barbiellini, G.; Longo, F.; Moretti, E. (INFN Ts); Picozza, P.; Morselli, A. (INFN and Univ. Roma Tor Vergata); Prest, M.; Vallazza, E. (Universita' dell'Insubria); Lipari, P.; Zanello, D. (INFN and Univ. Roma Sapienza); Cattaneo, P. W.; Rappoldi, A. (INFN Pv); Pittori, C.; Verrecchia, F.; Santolamazza, P.; Lucarelli, F.; Colafrancesco, S.; Giommi, P. (ASDC); Salotti, L. (ASI)
on 6 Jul 2010; 17:04 UT
Password Certification: Ettore Del Monte (ettore.delmonte@iasf-roma.inaf.it)

Subjects: X-ray, Binaries, Black Holes
Referred to by ATel #: 2734, 2751, 2755

Following the MAXI/GSC (ATel #2711) and RXTE/ASM (ATel #2714) detection of a spectral softening of the BHC Cyg X-1, we requested and obtained a SWIFT/XRT ToO observation of the source. The SWIFT/XRT observations were performed on 2010-07-02 between 14:06:17 UT and 18:27:40 UT in WT mode, for a total on-source time of about 6 ks distributed in three intervals of 2525 s, 2525 s and 885 s. We performed a spectral fit of the three observations using a model composed by an absorbed disc black body plus a power-law. Fit results are reported in the table below.
Begin Obs.
[UT]
NH
10E22cm-2]
kT [keV] Photon
Index
Unabs. Flux 2-10 keV
[10E-8ergs cm-2s-1]
2010-07-02
14:58:39
0.63 +/-
0.02
0.47 +/-
0.01
2.21 +/-
0.07
3.60
2010-07-02
16:35:00
0.63 +/-
0.01
0.52 +/-
0.01
2.09 +/-
0.06
4.10
2010-07-02
18:11:21
0.64 +/-
0.02
0.51 +/-
0.01
2.20 +/-
0.10
3.53
Following Zdziarski et al., ApJ, 578, 357 (2002) and Malzac et al., Procs. ESA SP-604 (2006), the powerlaw photon indices from the fit show that the source has not completed the state transition at the epoch of the observations, but it was still in the intermediate spectral state (Belloni et al., ApJ, 472, L107, 1996). We thank the Swift team for their prompt scheduling of these observations.

 

AGILE gamma-ray detection of Cygnus X-1

ATel #2715; S. Sabatini (INAF/IASF-Rm), E. Striani (Univ. Roma Tor Vergata and INFN Roma), F. Verrecchia(ASDC), M. Tavani (INAF/IASF-Rm, and Univ. Tor Vergata), Y. Evangelista, E. Del Monte (INAF/IASF-Rm), C. Pittori (ASDC), A. Bulgarelli, F. Gianotti, M. Trifoglio (INAF/IASF-Bo), I. Donnarumma, M. Feroci, F. Lazzarotto, L. Pacciani, P. Soffitta, E. Costa, I. Lapshov, M. Rapisarda, A. Argan, G. Piano, G. Pucella, A. Trois, V. Vittorini (INAF/IASF-Rm), A. Chen, A. Giuliani, S. Mereghetti, P. Caraveo, F. Perotti (INAF/IASF-Mi), A. Pellizzoni, M. Pilia (INAF/OA-Cagliari), G. Barbiellini, F. Longo, E. Moretti, E. Vallazza (INFN Trieste), F. Fuschino, M. Galli, C. Labanti, M. Marisaldi, G. Di Cocco (INAF/IASF-Bo), A. Morselli, P. Picozza (INFN and Univ. Roma Tor Vergata), M. Prest (Universita` dell'Insubria), P. Lipari, D. Zanello (INFN and Univ. Roma Sapienza), P.W. Cattaneo, A. Rappoldi (INFN Pavia), S. Vercellone, F. D'Ammando (INAF/IASF-Pa), F. Lucarelli, P. Santolamazza, S. Colafrancesco, P. Giommi (ASDC), L. Salotti (ASI)
on 2 Jul 2010; 13:37 UT
Password Certification: Sabina Sabatini (sabina.sabatini@iasf-roma.inaf.it)

Subjects: Gamma Ray, Binaries, Black Holes, Transients
Referred to by ATel #: 2734, 2751

Following the MAXI/GSC detection of a new soft X-ray brightening in Cygnus X-1 (ATel #2711) and the subsequent X-ray increased emission reported by RXTE-ASM (ATel #2714), indicating a possible transition of the source to the soft spectral state, we carried out follow up analysis for gamma-ray emission in AGILE data. Integrating from 2010-06-30 10:00 UT to 2010-07-02 10:00 UT, a maximum likelihood analysis yields a flux excess above 100 x 10E-8 ph/cm2/s (E > 100 MeV) in a position consistent with the black hole binary Cygnus X-1. We note that AGILE has monitored the Cygnus region since July 2007 and the 2-sigma upper limit for the gamma-ray flux above 100 MeV is 3x10E-8 ph/cm2/s at the position of Cygnus X-1. Gamma-ray flaring activity for a source positionally consistent with Cygnus X-1 was previously reported by AGILE in ATel #2512 with a flux above 250x10E-8 ph/cm2/s. These measurements were obtained with AGILE observing a large portion of the sky in a spinning mode.

 

Swift follow-up of the blazar 4C+21.35 (PKS 1222+21) after a bright gamma-ray flare

ATel #2698; F. Verrecchia, M. Capalbi, C. Pittori (ASDC), S. Vercellone (INAF/IASF-Pa), M. Tavani (INAF/IASF-Rm, and Univ. Tor Vergata), P. Giommi (ASDC), and F. D'Ammando (INAF/IASF-Pa), D. Donato (NASA/GSFC), G. Iafrate (INAF/OATs Trieste), Y. Tanaka (ISAS/JAXA) on behalf of the AGILE and Fermi Collaborations
on 26 Jun 2010; 16:58 UT
Distributed as an Instant Email Notice (Request for Observations)
Password Certification: Francesco Verrecchia (francesco.verrecchia@asdc.asi.it)

Subjects: Optical, Ultra-Violet, X-ray, Gamma Ray, >GeV, AGN, Blazars, Quasars
Referred to by ATel #: 2708

Following the AGILE/GRID (ATel #2686) and Fermi/LAT (ATel #2687) detection of a gamma-ray flare on June 19, 2010, from a source positionally consistent with the Flat Spectrum Radio Quasar 4C +21.35 (also known as PKS 1222+21 and 1FGL J1224.7+2121; R.A.=12h24m54.5s, Dec=+21d22m46.4s, J2000) at z=0.43, six Swift Target of Opportunity observations were performed between 20 and 23 June. The Swift/XRT data were taken in Photon Counting mode for a total exposure time of 13.5 ks, while the Swift/UVOT was operated with all filters. The mean XRT spectrum in the range 0.3-10 keV can be described with an absorbed power law model with a column density fixed to the galactic value (N_H=2.1e20 cm^-2, Kalberla et al. 2005, A&A, 440, 775) and a photon index 1.63 +/- 0.06. The unabsorbed 0.3-10 keV mean flux was (5.6 +/- 0.2)e-12 ergs/cm^2/s. The X-ray flux does not show significant variability among the observations. The Swift/UVOT detected the source at the following mean magnitudes:
Filter Total Expos. Mag
V 1184.1 15.25+/-0.05
B 1208.6 15.38+/-0.05
U 1262.7 14.40+/-0.04
UVW1 2660.8 14.12+/-0.02
UVM2 4483.7 13.93+/-0.03
UVW2 4745.0 13.93+/-0.05
The optical/UV bands photometry are compatible within 2 sigma with a constant flux. Further multiwavelength observations of the source are encouraged. We thank the Swift team for their rapid scheduling of these observations.

 

AGILE detection of a gamma-ray flare from the blazar 4C+21.35 (PKS 1222+21)

ATel #2686; E. Striani (Univ. Roma Tor Vergata and INFN Roma), F. Verrecchia (ASDC), I. Donnarumma (INAF/IASF-Rm), S. Vercellone (INAF/IASF-Pa), M. Tavani (INAF/IASF-Rm, and Univ. Tor Vergata), A. Bulgarelli, F. Gianotti, M. Trifoglio (INAF/IASF-Bo), A. Chen, A. Giuliani, S. Mereghetti, P. Caraveo, F. Perotti (INAF/IASF-Mi), F. D'Ammando (INAF/IASF-Pa), E. Del Monte, Y. Evangelista, M. Feroci, F. Lazzarotto, L. Pacciani, P. Soffitta, E. Costa, I. Lapshov, M. Rapisarda, A. Argan, G. Piano, G. Pucella, S. Sabatini, A. Trois, V. Vittorini (INAF/IASF-Rm), F. Fuschino, M. Galli, C. Labanti, M. Marisaldi, G. Di Cocco (INAF/IASF-Bo), A. Pellizzoni, M. Pilia (INAF/OA-Cagliari), G. Barbiellini, F. Longo, E. Moretti, E. Vallazza (INFN Trieste), A. Morselli, P. Picozza (INFN and Univ. Roma Tor Vergata), M. Prest (Universita` dell'Insubria), P. Lipari, D. Zanello (INFN and Univ. Roma Sapienza), P.W. Cattaneo, A. Rappoldi (INFN Pavia), C. Pittori, F. Lucarelli, P. Santolamazza, S. Colafrancesco, P. Giommi (ASDC), L. Salotti (ASI)
on 19 Jun 2010; 15:35 UT
Distributed as an Instant Email Notice (Request for Observations)
Password Certification: Francesco Verrecchia (francesco.verrecchia@asdc.asi.it)

Subjects: Gamma Ray, >GeV, VHE, Request for Observations, AGN, Blazars, Quasars
Referred to by ATel #: 2687, 2688, 2693, 2698, 2708

AGILE is detecting intense gamma-ray emission above 100 MeV from a source consistent with the Flat Spectrum Radio Quasar PKS 1222+21 (R.A.=186.2, Dec.=21.4). Integrating from 2010-06-17 09:20 UT to 2010-05-19 09:30 UT, a maximum likelihood analysis yields a detection at a significance level of about 9 sigma, and a flux F = (6.5+/-1.3) 10-6 ph/cm2/s (E > 100 MeV), which correspond to an increase of about a factor of 2 with respect to the previous 48 hours. This detection followed an activity in VHE reported by MAGIC collaboration in ATel #2684. An increased gamma-ray activity from a source consistent with the blazar PKS 1222+21 was previously reported by AGILE/GRID (ATel #2641, #2348) and Fermi/LAT (ATel #2584, #2349). The AGILE-GRID detection was obtained while AGILE is observing in spinning mode, surveying a large fraction of the sky each day. Multifrequency observations of PKS 1222+21 are strongly encouraged.

 

AGILE detection of gamma-ray emission from Cygnus X-3

ATel #2645; A. Bulgarelli (INAF/IASF Bologna), M. Tavani (INAF/IASF Roma), F. Gianotti, M. Trifoglio (INAF/IASF Bologna), E. Striani (Univ. Tor Vergata), C. Pittori, F. Verrecchia (ASDC), S. Sabatini, G. Piano (INAF/IASF Roma), A. Argan, A. Trois, G. De Paris, V. Vittorini, E. Costa, I. Donnarumma, M. Feroci, L. Pacciani, E. Del Monte, F. Lazzarotto, P. Soffitta, Y. Evangelista, I. Lapshov (INAF-IASF-Rm), A. Chen, A. Giuliani (INAF-IASF-Milano), M. Marisaldi, G. Di Cocco, C. Labanti, F. Fuschino, M. Galli (INAF/IASF Bologna), P. Caraveo, S. Mereghetti, F. Perotti (INAF/IASF Milano), G. Pucella, M. Rapisarda (ENEA-Roma), A. Pellizzoni, M. Pilia (INAF/OA-Cagliari), G. Barbiellini, F. Longo (INFN Trieste), P. Picozza, A. Morselli (INFN and Univ. Tor Vergata), M. Prest (Universita` dell'Insubria), Verrecchia (ASDC), S. Sabatini, G. Piano (INAF/IASF Roma), F. D'Ammando, S. Vercellone (INAF/IASF-Palermo), P. Lipari, D. Zanello (INFN Roma-1), P.W. Cattaneo, A. Rappoldi (INFN Pavia), P. Giommi, P. Santolamazza, F. Lucarelli, S. Colafrancesco, (ASDC), L. Salotti (ASI)
on 27 May 2010; 20:13 UT
Distributed as an Instant Email Notice (Transients)
Password Certification: Marco Tavani (tavani@iasf-roma.inaf.it)

Subjects: Gamma Ray, Black Holes, Neutron Stars, Transients

AGILE is currently detecting excess gamma-ray flux above 100 MeV from the microquasar Cygnus X-3. A quicklook analysis of gamma-ray data shows significant flux from a source positionally consistent with Cygnus X-3 during the period 2010-05-25 UT 19:10 to 2010-05-27 UT 17:04. Multifrequency observations of Cygnus X-3 are strongly encouraged.

 

AGILE detection of gamma-ray emission from 4C+21.35 (PKS 1222+21)

ATel #2641; A. Bulgarelli, F. Gianotti, M. Trifoglio (INAF/IASF Bologna), M. Tavani (INAF/IASF Roma), S. Vercellone (INAF/IASF Palermo), E. Striani (Univ. Tor Vergata), C. Pittori, F. Verrecchia (ASDC), S. Sabatini, G. Piano (INAF/IASF Roma), F. D'Ammando (INAF/IASF Palermo), A. Argan, A. Trois, G. De Paris, V. Vittorini, E. Costa, I. Donnarumma, M. Feroci, L. Pacciani, E. Del Monte, F. Lazzarotto, P. Soffitta, Y. Evangelista, I. Lapshov (INAF/IASF Roma), A. Chen, A. Giuliani (INAF/IASF Milano), M. Marisaldi, G. Di Cocco, C. Labanti, F. Fuschino, M. Galli (INAF/IASF Bologna), P. Caraveo, S. Mereghetti, F. Perotti (INAF/IASF Milano), G. Pucella, M. Rapisarda (ENEA-Roma), A. Pellizzoni, M. Pilia (INAF/OA-Cagliari), G. Barbiellini, F. Longo (INFN Trieste), P. Picozza, A. Morselli (INFN and Univ. Tor Vergata), M. Prest (Universita` dell'Insubria), P. Lipari, D. Zanello (INFN Roma-1), P.W. Cattaneo, A. Rappoldi (INFN Pavia), P. Giommi, P. Santolamazza, F. Lucarelli, S. Colafrancesco, (ASDC), L. Salotti (ASI)
on 26 May 2010; 12:44 UT
Distributed as an Instant Email Notice (Request for Observations)
Password Certification: Francesco Verrecchia (francesco.verrecchia@asdc.asi.it)

Subjects: Gamma Ray, >GeV, Request for Observations, AGN, Blazars, Quasars
Referred to by ATel #: 2684, 2686, 2687

AGILE is detecting an increasing gamma-ray flux above 100 MeV from a source positionally consistent with the blazar 4C+21.35 (RA: 185.597558, Dec: 21.656435). Integrating from 2010-05-23 14:30 UT to 2010-05-26 05:22 UT, a quicklook maximum likelihood analysis yields a detection centered at Galactic coordinates (l,b) = (255.07, 81.7) ± 0.4 deg (stat.) ± 0.1 deg (syst.) (R.A. = 12h 25m 1.72s, Dec. = 21h 24m 29.8s ) with a significance level above 7 sigma and gamma-ray flux above 300 e-8 ph/cm2/sec for photon energies larger than 100 MeV. This detection of PKS 1222+21 turns out to be the most significant one since the beginning of operations of AGILE in spinning mode (early November 2009). The source may start a phase of rising gamma-ray emission as previously detected in recent months (ATel #2021, #2348, #2349, #2584, #2617, #2626). Multifrequency observations of PKS 1222+21 are strongly encouraged.

 

AGILE detection of gamma-ray emission from the Cygnus X-3 region

ATel #2609; A. Bulgarelli (INAF/IASF Bologna), E. Striani (Univ. Tor Vergata), S. Sabatini, G. Piano, M. Tavani (INAF/IASF Roma), F. Gianotti, M. Trifoglio (INAF/IASF Bologna), G. Pooley (Cavendish Lab., Cambridge UK), M. McCollough (Smithsonian Astrophys. Observatory),C. Pittori, F. Verrecchia (ASDC), A. Argan, A. Trois, G. De Paris, V. Vittorini, F. D'Ammando, E. Costa, I. Donnarumma, M. Feroci, L. Pacciani, E. Del Monte, F. Lazzarotto, P. Soffitta, Y. Evangelista, I. Lapshov (INAF-IASF-Rm), A. Chen, A. Giuliani(INAF-IASF-Milano), M. Marisaldi, G. Di Cocco, C. Labanti, F. Fuschino, M. Galli (INAF/IASF Bologna), P. Caraveo, S. Mereghetti, F. Perotti (INAF/IASF Milano), G. Pucella, M. Rapisarda (ENEA-Roma), S. Vercellone (IASF-Pa), A. Pellizzoni, M. Pilia (INAF/OA-Cagliari), G. Barbiellini, F. Longo (INFN Trieste), P. Picozza, A. Morselli (INFN and Univ. Tor Vergata), M. Prest (Universita` dell'Insubria), P. Lipari, D. Zanello (INFN Roma-1), P.W. Cattaneo, A. Rappoldi (INFN Pavia), P. Giommi, P. Santolamazza, S. Colafrancesco, (ASDC), L. Salotti (ASI)
on 10 May 2010; 18:38 UT
Distributed as an Instant Email Notice (Transients)
Password Certification: Marco Tavani (tavani@iasf-roma.inaf.it)

Subjects: X-ray, Gamma Ray, Black Holes, Neutron Stars, Transients
Referred to by ATel #: 2611, 2644, 2646

AGILE is detecting a gamma-ray source positionally consistent with the microquasar Cygnus X-3. Integrating during the period 2010-05-07 14:53 UT to 2010-05-09 17:19 UT (MJD= 55323.6-55325.7) the AGILE-GRID detected gamma-ray emission above 100 MeV from a source at Galactic coordinates (l,b) = (79.1,1.1) +/- 0.8(stat.) +/- 0.1 (syst.) deg, and flux F > 100 e-8 ph/cm2/sec above 100 MeV (2-day significance in spinning mode above 3.5 sigma). We notice that the hard X-ray lightcurve of Cyg X-3 as monitored by the BAT/Swift instrument (public data available at http:///heasarc.gsfc.nasa.gov/docs/swift/results/transients/CygX-3 ) shows an overall decreasing trend starting on approximately MJD = 55311. A local minimum was reached on May 9th, 2010 (MJD=55325) in coincidence with the AGILE-GRID detection. This trend of decreasing hard X-ray emission in conjunction with gamma-ray flaring activity of Cyg X-3 was already detected in June, 2009. We strongly encourage multifrequency observations of Cyg X-3.

 

AGILE detection of the new unidentified gamma-ray source AGL J0906-1241

ATel #2552; C. Pittori, F. Verrecchia (ASDC), E. Striani (Univ. Roma Tor Vergata and INFN Roma), M. Tavani (INAF/IASF-Rm), S. Vercellone (INAF/IASF-Pa), S. Sabatini (INAF/IASF-Rm), A. Bulgarelli, F. Gianotti, M. Trifoglio (INAF/IASF-Bo), and Univ. Tor Vergata), A. Chen, A. Giuliani, S. Mereghetti, P. Caraveo, F. Perotti (INAF/IASF-Mi), I. Donnarumma (INAF/IASF-Rm), F. D'Ammando (Univ. Roma Tor Vergata and INAF/IASF-Rm), E. Del Monte, Y. Evangelista, M. Feroci, F. Lazzarotto, L. Pacciani, P. Soffitta, E. Costa, I. Lapshov, M. Rapisarda, A. Argan, G. Piano, G. Pucella, A. Trois, V. Vittorini (INAF/IASF-Rm), F. Fuschino, M. Galli, C. Labanti, M. Marisaldi, G. Di Cocco (INAF/IASF-Bo), A. Pellizzoni, M. Pilia (INAF/OA-Cagliari), G. Barbiellini, F. Longo, E. Moretti, E. Vallazza (INFN Trieste), A. Morselli, P. Picozza (INFN and Univ. Roma Tor Vergata), M. Prest (Universita` dell'Insubria), P. Lipari, D. Zanello (INFN and Univ. Roma Sapienza), P.W. Cattaneo, A. Rappoldi (INFN Pavia), F. Lucarelli, P. Santolamazza, S. Colafrancesco, P. Giommi (ASDC), L. Salotti (ASI)
on 13 Apr 2010; 15:14 UT
Distributed as an Instant Email Notice (Request for Observations)
Password Certification: Carlotta Pittori (carlotta.pittori@asdc.asi.it)

Subjects: Gamma Ray, >GeV, Request for Observations, Transients

AGILE is detecting intense gamma-ray emission above 100 MeV from a new unidentified source, AGL J0906-1241 with Galactic coordinates (l, b) = (241.5, 22.4) +/- 0.8 deg (95% stat. c.l.) +/- 0.1 deg (syst.), (R.A.: 136.5, Dec: -12.7). Integrating from 2010-04-11 05:00 UT to 2010-04-13 06:00 UT, a maximum likelihood analysis yields a detection at a significance level larger than 5 sigma, and a flux F = (3.8+/-1.2) 10-6 ph/cm2/s (E > 100 MeV). No prominent extragalactic or Galactic source is known within the error box of AGL J0906-1241. This measurement was obtained with AGILE observing a large portion of the sky in a spinning mode. Multifrequency observations of the AGL J0906-1241 error box are strongly encouraged.

 

AGILE detects enhanced gamma-ray emission from the blazar PKS 2142-758

ATel #2551; F. Verrecchia (ASDC), E. Striani (Univ. Roma Tor Vergata), C. Pittori, F. Lucarelli (ASDC), S. Vercellone (INAF/IASF-Pa), M. Tavani (INAF/IASF-Rm), A. Bulgarelli (INAF/IASF-Bo), F. D'Ammando (INAF/IASF-Pa), I. Donnarumma (INAF/IASF-Rm), V. Vittorini, E. Del Monte, Y. Evangelista, M. Feroci, F. Lazzarotto, L. Pacciani, P. Soffitta, E. Costa, I. Lapshov, M. Rapisarda, A. Argan, G. Piano, G. Pucella, S. Sabatini, A. Trois (INAF/IASF-Rm), F. Fuschino, M. Galli, F. Gianotti, C. Labanti, M. Marisaldi, M. Trifoglio, G. Di Cocco (INAF/IASF-Bo), A. Chen, A. Giuliani, S. Mereghetti, P. Caraveo, F. Perotti (INAF/IASF-Mi), A. Pellizzoni, M. Pilia (INAF/OA-Cagliari), G. Barbiellini, F. Longo, E. Moretti, E. Vallazza (INFN Trieste), A. Morselli, P. Picozza (INFN and Univ. Roma Tor Vergata), M. Prest (Universita` dell'Insubria), P. Lipari, D. Zanello (INFN and Univ. Roma Sapienza), P.W. Cattaneo, A. Rappoldi (INFN Pavia), P. Santolamazza, S. Colafrancesco, P. Giommi (ASDC), L. Salotti (ASI)
on 13 Apr 2010; 14:50 UT
Distributed as an Instant Email Notice (Request for Observations)
Password Certification: Francesco Verrecchia (francesco.verrecchia@asdc.asi.it)

Subjects: Gamma Ray, >GeV, Request for Observations, AGN, Quasars

AGILE has been detecting during the last 2 days an increasing gamma-ray flux above 100 MeV from a source positionally consistent with the blazar PKS 2142-758 (RA: 326.803, Dec: -75.603). Integrating from 2010-04-10 11:30 UT to 2010-04-12 21:00 UT, a quick-look maximum likelihood analysis yields a detection at a significance level of about 5 sigma and a source flux F=(2.6 +/- 0.9) x 10-6 ph/cm2/sec (E > 100 MeV). The AGILE-GRID detection was obtained while AGILE is observing in spinning mode, surveying a large fraction of the sky each day. Multifrequency observations of the source are strongly encouraged.

 

AGILE detection of a gamma ray flare from the Cygnus X-1 region

ATel #2512; A. Bulgarelli (INAF/IASF-Bo), C. Pittori, F. Lucarelli (ASDC), E. Striani (Univ. Roma Tor Vergata and INFN Roma), F. Gianotti, M. Trifoglio (INAF/IASF-Bo), S. Sabatini, M. Tavani (INAF/IASF-Rm, and Univ. Tor Vergata), F. Verrecchia (ASDC), A. Trois (INAF/IASF-Rm), A. Chen, A. Giuliani, S. Mereghetti, P. Caraveo, F. Perotti (INAF/IASF-Mi), S. Vercellone, F. D'Ammando (INAF/IASF-Pa), I. Donnarumma, E. Del Monte, Y. Evangelista, M. Feroci, F. Lazzarotto, L. Pacciani, P. Soffitta, E. Costa, I. Lapshov, M. Rapisarda, A. Argan, G. Piano, G. Pucella, V. Vittorini (INAF/IASF-Rm), F. Fuschino, M. Galli, C. Labanti, M. Marisaldi, G. Di Cocco (INAF/IASF-Bo), A. Pellizzoni, M. Pilia (INAF/OA-Cagliari), G. Barbiellini, F. Longo, E. Moretti, E. Vallazza (INFN Trieste), A. Morselli, P. Picozza (INFN and Univ. Roma Tor Vergata), M. Prest (Universita` dell'Insubria), P. Lipari, D. Zanello (INFN and Univ. Roma Sapienza), P.W. Cattaneo, A. Rappoldi (INFN Pavia), P. Santolamazza, S. Colafrancesco, P. Giommi (ASDC) and L. Salotti (ASI)
on 25 Mar 2010; 17:22 UT
Distributed as an Instant Email Notice (Request for Observations)
Password Certification: Sabina Sabatini (sabina.sabatini@iasf-roma.inaf.it)

Subjects: Gamma Ray, >GeV, Request for Observations, Transients
Referred to by ATel #: 2715, 2751

AGILE is detecting an intense gamma-ray emission above 100 MeV from a source of Galactic coordinates (l, b) = (70.3 2.5) ± 1.2 deg (95% stat. c.l. and systematic error) (1-day integration). Integrating from 2010-03-24 02:24 UT to 2010-03-25 01:01 UT, a maximum likelihood analysis yields a detection at a significance level of about 5 sigma, and a flux above 250 10-8 ph/cm2/s (E > 100 MeV). For a 2-days integration (2010-03-23 05:05 UT to 2010-03-25 04:25 UT) a maximum likelihood analysis yields a detection of 3.7 sigma with a flux of (200 ± 90) 10-8 ph/cm2/s for E > 100 MeV. We note that the black-hole binary Cygnus X-1 and 1FGLJ1958.9+3459 are within the source error box. These measurements were obtained with AGILE observing a large portion of the sky in a spinning mode. Multifrequency observations of the Cygnus X-1 region are strongly encouraged.

 

AGILE detects enhanced gamma-ray emission from the blazar PKS 0402-362

ATel #2484; E. Striani (Univ. Roma Tor Vergata), F. Verrecchia, C. Pittori, F. Lucarelli (ASDC), S. Vercellone (INAF/IASF-Pa), M. Tavani (INAF/IASF-Rm), A. Bulgarelli (INAF/IASF-Bo), F. D'Ammando (INAF/IASF-Pa), I. Donnarumma (INAF/IASF-Rm), V. Vittorini, E. Del Monte, Y. Evangelista, M. Feroci, F. Lazzarotto, L. Pacciani, P. Soffitta, E. Costa, I. Lapshov, M. Rapisarda, A. Argan, G. Piano, G. Pucella, S. Sabatini, A. Trois (INAF/IASF-Rm), F. Fuschino, M. Galli, F. Gianotti, C. Labanti, M. Marisaldi, M. Trifoglio, G. Di Cocco (INAF/IASF-Bo), A. Chen, A. Giuliani, S. Mereghetti, P. Caraveo, F. Perotti (INAF/IASF-Mi), A. Pellizzoni, M. Pilia (INAF/OA-Cagliari), G. Barbiellini, F. Longo, E. Moretti, E. Vallazza (INFN Trieste), A. Morselli, P. Picozza (INFN and Univ. Roma Tor Vergata), M. Prest (Universita` dell'Insubria), P. Lipari, D. Zanello (INFN and Univ. Roma Sapienza), P.W. Cattaneo, A. Rappoldi (INFN Pavia), P. Santolamazza, S. Colafrancesco, P. Giommi (ASDC), L. Salotti (ASI)
on 16 Mar 2010; 20:17 UT
Distributed as an Instant Email Notice (Request for Observations)
Password Certification: Carlotta Pittori (carlotta.pittori@asdc.asi.it)

Subjects: Gamma Ray, >GeV, Request for Observations, AGN, Quasars

AGILE has been detecting during the last 3 days an increasing gamma-ray flux above 100 MeV from a source positionally consistent with the blazar PKS 0402-362 (RA: 04h02m02.5994s, Dec: -36d13m11.947s). Integrating from 2010-03-13 12:00 UT to 2010-03-16 15:00 UT, a quick-look maximum likelihood analysis yields a detection at a significance level of about 5 sigma and a source flux of about F=(2.2 +/- 0.8) x 10-6 ph/cm2/sec (E > 100 MeV). The detection of a previous GeV flare from PKS 0402-362 was reported by Fermi/LAT in ATel #2413 on February 2, 2010. The AGILE-GRID detection was obtained while AGILE is observing in spinning mode, surveying a large fraction of the sky each day. Multifrequency observations of the source are strongly encouraged.

 

Spectral transition of 4U 1608-522 during the undergoing 2010 outburst

ATel #2467; E. Del Monte, R. Campana, I. Donnarumma, Y. Evangelista, M. Feroci (INAF-IASF Roma), D. Altamirano, D. M. Russell (Univ. of Amsterdam), P. Casella (Univ. of Southampton), E. Kuulkers, C. Sanchez-Fernandez (ESA/ESAC), F. Lewis (Faulkes Telescope Project, University of Glamorgan, Open University) and J. J. M. in 't Zand (SRON)
on 9 Mar 2010; 9:46 UT
Password Certification: Ettore Del Monte (ettore.delmonte@iasf-roma.inaf.it)

Subjects: X-ray, Binaries, Neutron Stars, Transients

Following the SuperAGILE detection of an X-ray burst from the neutron star transient and atoll source 4U 1608-522 (ATel #2461), on 3 March 2010 at 06:33:25 UT, marking the beginning of a new outburst, as confirmed by the MAXI (ATel #2462) and INTEGRAL (ATel #2464) detection of increased persistent emission, we obtained Swift and RXTE target of opportunity observations. We find that the source switched to a soft spectral state between the two Swift observations. In the first one, which started about 53 ks after the SuperAGILE X-ray burst, the counting rate of RXTE/ASM was about 2 cts/s (roughly 30 mCrab; 2 - 12 keV) and the spectrum is described by an absorbed power-law with photon index of 2.13 +/- 0.07 and unabsorbed flux (2 - 10 keV) of 6*10^-10 erg/cm^2/s. In the second observation, which started about 359 ks after the X-ray burst, the RXTE/ASM counting rate was about 30 cts/s (about 400 mCrab; 2 - 12 keV). At that time the spectrum is described by a blackbody (with kT = 0.96 +/- 0.05 keV) plus a power-law of 1.82 +/- 0.06 photon index, with unabsorbed flux of 9*10^-9 erg/cm^2/s (2 - 10 keV). In both spectra we assume a Galactic column density of 1.2*10^22 cm^-2 (e.g., Tarana et al., 2008, ApJ, 688, 1295), compatible with the range found in the literature (1 - 2 *10^22 cm^-2, Penninx et al., 1989, A&A 208, 146). Assuming a distance of 5.8 kpc (Guver et al. 2010, arXiv:0811.3979), between the two XRT observations the unabsorbed source luminosity increased from about 2*10^36 erg/s up to about 4*10^37 erg/s. No bursts were detected during the Swift observations. The RXTE/PCA ToO campaign started about 130 ks after the SuperAGILE X-ray burst and at that time the source was already in the soft spectral state. The flux in the 2 - 16 keV energy range increased from about 50 mCrabup to more than 500 mCrab in about four days. With an observing strategy of daily frequency, only four X-ray bursts were detected, all within a time range of 12 ks. From a preliminary analysis, only in one of the bursts oscillations were detected, at a frequency of 619 Hz, consistent with other episodes reported in literature for the same source. We would like to thank the Swift and RXTE Teams for making these observations possible, in particular the duty scientists as well as the science planners.

 

SuperAGILE detection of an X-ray burst from 4U 1608-522

ATel #2461; E. Del Monte, I. Donnarumma, L. Pacciani, Y. Evangelista, M. Feroci, F. Lazzarotto, P. Soffitta, E. Costa, I. Lapshov, M. Rapisarda (INAF/IASF Rome), A. Giuliani, A. Chen, S. Mereghetti, F. Perotti, P. Caraveo (INAF/IASF Milan), A. Pellizzoni, M. Pilia (INAF/OA Cagliari), F. D'Ammando, S. Vercellone (INAF/IASF Palermo), A. Bulgarelli, F. Gianotti, M. Trifoglio, G. Di Cocco, C. Labanti, F. Fuschino, M. Marisaldi, M. Galli, (INAF/IASF Bologna), M. Tavani, V. Vittorini, E. Striani, A. Argan, A. Trois, G. Piano, S. Sabatini (INAF/IASF Rome), G. Barbiellini, F. Longo, E. Moretti (INFN Trieste), P. Picozza, A. Morselli (INFN Roma-2), M. Prest, E. Vallazza (Universita` dell'Insubria), P. Lipari, D. Zanello (INFN Roma-1), P.W. Cattaneo, A. Rappoldi (INFN Pavia), and C. Pittori, F. Verrecchia, P. Santolamazza, F. Lucarelli, S. Colafrancesco, P. Giommi (ASDC) and L. Salotti (ASI)
on 3 Mar 2010; 14:22 UT
Password Certification: Ettore Del Monte (ettore.delmonte@iasf-roma.inaf.it)

Subjects: X-ray, Request for Observations, Binaries, Neutron Stars, Transients
Referred to by ATel #: 2462, 2464, 2467

On 3 March 2010, at 06:33:25 UT SuperAGILE detected an X-ray burst with duration of about 8 s. The detection is statistically significant only in the energy band 17 - 25 keV. The burst was localized at coordinates RA=243.1868 (16h 12m 44.83s), dec=-52.4192 (-52d 25' 08.97"), with 3 arcmin error radius, in a position consistent with the neutron star transient and atoll source 4U 1608-522, that lies at a distance of about 0.4 arcmin from the SuperAGILE localization. In the energy range between 17 and 25 keV, assuming a blackbody spectrum with a temperature of 3 keV, the observed rate corresponds to an average flux of 5*10^-9 erg/cm^2/s and to a fluence of 4*10^-8 erg/cm^2. Taking into account a distance of 5.8 kpc and a mass of 1.74 solar masses (Guver et al. 2010, arXiv:0811.3979v4), the luminosity of the burst is 2.1*10^37 erg/s and corresponds to about 0.1 Eddington luminosity. The source was announced on October 2009 to have returned to a quiescent state after the 2007-2009 outburst (Linares et al. 2009, ATel #2264).

 

AGILE detects enhanced gamma-ray emission from the blazar PKS 0537-441

ATel #2454; F. Lucarelli (ASDC), E. Striani (Univ. Roma Tor Vergata and INFN Roma), F. D'Ammando (INAF/IASF-Pa), F. Verrecchia, C. Pittori (ASDC), M. Tavani (INAF/IASF-Rm), S. Vercellone(INAF/IASF-Pa), E. Del Monte, I. Donnarumma, Y. Evangelista, M. Feroci, F. Lazzarotto, L. Pacciani, P. Soffitta, E. Costa, I. Lapshov, M. Rapisarda, A. Argan, G. Piano, G. Pucella, S. Sabatini, A. Trois, V. Vittorini (INAF/IASF-Rm), A. Bulgarelli, F. Gianotti, M. Trifoglio, F. Fuschino, M. Galli, C. Labanti, M. Marisaldi, G. Di Cocco (INAF/IASF-Bo), A. Chen, A. Giuliani, S. Mereghetti, P. Caraveo, F. Perotti (INAF/IASF-Mi), A. Pellizzoni, M. Pilia (INAF/OA-Cagliari), G. Barbiellini, F. Longo, E. Moretti, E. Vallazza (INFN Trieste), A. Morselli, P. Picozza (INFN and Univ. Roma Tor Vergata), M. Prest (Universita` dell'Insubria), P. Lipari, D. Zanello (INFN and Univ. Roma Sapienza), P.W. Cattaneo, A. Rappoldi (INFN Pavia), P. Santolamazza, S. Colafrancesco, P. Giommi (ASDC), L. Salotti (ASI)
on 24 Feb 2010; 11:27 UT
Password Certification: Carlotta Pittori (carlotta.pittori@asdc.asi.it)

Subjects: Gamma Ray, >GeV, Request for Observations, AGN, Quasars

AGILE is detecting during the last 5 days enhanced gamma-ray emission above 100 MeV from a source positionally consistent with the blazar PKS 0537-441. PKS 0537-441, RA=05 38 29.6, DEC=-44 24 17.8 (J2000), is a low-energy peaked BL Lac with redshift z=0.894 (Peterson et al. 1976, Apj 207). Its mean flux above 100 MeV, as measured in the First AGILE Catalog (Pittori et al. 2009, A&A 506) during the first year of observations, was (43+/-10)x10^-8 ph/cm2/s. Integrating from 2010-02-18 00:00 UT to 2010-02-23 10:30 UT, a quicklook maximum likelihood analysis yields a detection of PKS 0537-441 at a significance level of about 5 sigma and flux F = (150+/-50)x10^-8 ph/cm2/s (E > 100 MeV), roughly 3 times the source gamma-ray average flux (43+/-10)x10^-8 ph/cm2/s, as measured by AGILE during the first year of observations (Pittori et al. 2009, A&A 506). Fermi LAT reported past flaring activity from this Blazar in the ATels 2124 and 1759. The AGILE detection was obtained with the satellite observing in a spinning mode, surveying a large fraction of the sky every day. Multifrequency observations of PKS 0537-441 are strongly encouraged.

 

AGILE confirmation of the new gamma-ray flaring source J0109+6134 near the Galactic plane

ATel #2416; S. Sabatini, M. Tavani (INAF/IASF Roma), A. Bulgarelli, F. Gianotti, M. Trifoglio (INAF/IASF Bologna), E. Striani (Univ. Tor Vergata), F. Verrecchia, C. Pittori (ASDC), A. Argan, A. Trois, G. Piano, V. Vittorini, F. D'Ammando, E. Costa, I. Donnarumma, M. Feroci, L. Pacciani, E. Del Monte, F. Lazzarotto, P. Soffitta, Y. Evangelista, G. De Paris, I. Lapshov (INAF-IASF-Rm), A. Chen, A. Giuliani(INAF-IASF-Milano), M. Marisaldi, G. Di Cocco, C. Labanti, F. Fuschino, M. Galli (INAF/IASF Bologna), P. Caraveo, S. Mereghetti, A. Pellizzoni, F. Perotti (INAF/IASF Milano), G. Pucella, M. Rapisarda (ENEA-Roma), S. Vercellone (IASF-Pa), A. Pellizzoni, M. Pilia (INAF/OA-Cagliari), G. Barbiellini, F. Longo (INFN Trieste), P. Picozza, A. Morselli (INFN and Univ. Tor Vergata), M. Prest (Universita` dell'Insubria), P. Lipari, D. Zanello (INFN Roma-1), P.W. Cattaneo, A. Rappoldi (INFN Pavia), P. Giommi, F. Lucarelli, P. Santolamazza, S. Colafrancesco, (ASDC), L. Salotti (ASI)
on 3 Feb 2010; 17:09 UT
Password Certification: Marco Tavani (tavani@iasf-roma.inaf.it)

Subjects: Gamma Ray, Transients
Referred to by ATel #: 2420, 2421, 2428, 2433, 2460

AGILE confirms the detection of the new flaring gamma-ray source J0109+6134 near the Galactic plane as reported by Fermi-LAT in ATel#2414. Integrating during the period 2010-01-31 08:20 UT to 2010-02-02 19:48 UT AGILE detected gamma-ray emission above 100 MeV from a source positionally consistent with J0109+6134. A maximum likelihood analysis provides a 3-sigma detection of a source with flux F = (95+/-50) e-8 ph/cm2/sec above 100 MeV, at Galactic coordinates (l,b) = (125.18, -1.21) +/- 0.6 deg and celestial coordinates (J2000) R.A. = 01 10 21, Dec. = 61 34 45. An AGILE gamma-ray intensity map of the field above 100 MeV in Galactic coordinates for the period specified above (AGILE error box in green color and FERMI detection in grey color) can be found at http://www.asdc.asi.it/images/atel/transient_l125.jpg. No significant gamma-ray source within the error box of J0109+6134 was detected by AGILE from a deep data integration during the period July, 2007 - October, 2009. This detection was obtained with the AGILE satellite observing in a spinning mode, surveying a large fraction of the sky every day. We strongly encourage multifrequency observations of the J0109+6134 field.
AGILE gamma-ray intensity map of the J0109+6134 transient

 

AGILE detection of AGL J2206+6203, a new unidentified gamma-ray source

ATel #2403; A. Bulgarelli, F. Gianotti, M. Trifoglio (INAF/IASF-Bo), F. Lucarelli, C. Pittori, F. Verrecchia (ASDC), M. Tavani (INAF/IASF-Rm, and Univ. Tor Vergata), E. Striani (Univ. Roma Tor Vergata and INFN Roma), A. Chen, A. Giuliani, S. Mereghetti, P. Caraveo, F. Perotti (INAF/IASF-Mi), S. Vercellone (INAF/IASF-Pa), I. Donnarumma (INAF/IASF-Rm), F. D'Ammando (Univ. Roma Tor Vergata and INAF/IASF-Rm), E. Del Monte, Y. Evangelista, M. Feroci, F. Lazzarotto, L. Pacciani, P. Soffitta, E. Costa, I. Lapshov, M. Rapisarda, A. Argan, G. Piano, G. Pucella, S. Sabatini, A. Trois, V. Vittorini (INAF/IASF-Rm), F. Fuschino, M. Galli, C. Labanti, M. Marisaldi, G. Di Cocco (INAF/IASF-Bo), A. Pellizzoni, M. Pilia (INAF/OA-Cagliari), G. Barbiellini, F. Longo, E. Moretti, E. Vallazza (INFN Trieste), A. Morselli, P. Picozza (INFN and Univ. Roma Tor Vergata), M. Prest (Universita` dell'Insubria), P. Lipari, D. Zanello (INFN and Univ. Roma Sapienza), P.W. Cattaneo, A. Rappoldi (INFN Pavia), P. Santolamazza, S. Colafrancesco, P. Giommi (ASDC) and L. Salotti (ASI)
on 25 Jan 2010; 17:47 UT
Distributed as an Instant Email Notice (Request for Observations)
Password Certification: Carlotta Pittori (carlotta.pittori@asdc.asi.it)

Subjects: Gamma Ray, >GeV, Request for Observations, Transients
Referred to by ATel #: 2405

AGILE is detecting intense gamma-ray emission above 100 MeV from a new unidentified source, AGL J2206+6203, with Galactic coordinates (l, b) = (104.9, 5.1) +/- 0.4 deg (95% stat. c.l.) +/- 0.1 deg (syst.), and Celestial coordinates R.A. (J2000) = 22 06 49.17, Dec. (J2000)= 62 03 45.2. Integrating from 2010-01-20 03:46 UT to 2010-01-25 11:15 UT, a maximum likelihood analysis yields a detection at a significance level larger than 5 sigma, and a flux F = (160+/-50) 10^-8 ph/cm2/s (E > 100 MeV). AGILE is detecting marginal (3 sigma) emission from this source above above 400 MeV. No prominent gamma-ray source is known within the error box of AGL J2206+6203. This measurement was obtained with AGILE observing a large portion of the sky in a spinning mode. Multifrequency observations of the AGL J2206+6203 error box are strongly encouraged.

 

AGILE detection of enhanced gamma-ray emission from the blazar PKS 1510-089

ATel #2385; E. Striani (Univ. Roma Tor Vergata and INFN Roma), F. Verrecchia (ASDC), M. Tavani (INAF/IASF-Rm), S. Vercellone (INAF/IASF-Pa), F. D'Ammando (Univ. Roma Tor Vergata and INAF/IASF-Rm), E. Del Monte, I. Donnarumma, Y. Evangelista, M. Feroci, F. Lazzarotto, L. Pacciani, P. Soffitta, E. Costa, I. Lapshov, M. Rapisarda, A. Argan, G. Piano, G. Pucella, S. Sabatini, A. Trois, V. Vittorini (INAF/IASF-Rm), A. Bulgarelli, F. Gianotti, M. Trifoglio, F. Fuschino, M. Galli, C. Labanti, M. Marisaldi, G. Di Cocco (INAF/IASF-Bo), A. Chen, A. Giuliani, S. Mereghetti, P. Caraveo, F. Perotti (INAF/IASF-Mi), A. Pellizzoni, M. Pilia (INAF/OA-Cagliari), G. Barbiellini, F. Longo, E. Moretti, E. Vallazza (INFN Trieste), A. Morselli, P. Picozza (INFN and Univ. Roma Tor Vergata), M. Prest (Universita` dell'Insubria), P. Lipari, D. Zanello (INFN and Univ. Roma Sapienza), P.W. Cattaneo, A. Rappoldi (INFN Pavia), C. Pittori, F. Lucarelli, P. Santolamazza, S. Colafrancesco, P. Giommi (ASDC), L. Salotti (ASI)
on 13 Jan 2010; 16:45 UT
Distributed as an Instant Email Notice (Request for Observations)
Password Certification: Francesco Verrecchia (francesco.verrecchia@asdc.asi.it)

Subjects: Gamma Ray, >GeV, Request for Observations, AGN, Quasars

AGILE is detecting during the last 48 hours enhanced gamma-ray emission above 100 MeV from a source positionally consistent with the blazar PKS 1510-089. Integrating from 2010-01-11 10:30 UT to 2010-01-13 10:30 UT, a quicklook maximum likelihood analysis yields a detection of PKS 1510-089 at a significance level above 5 sigma and flux above 300e-8 ph/cm2/s (E > 100 MeV). The AGILE detection was obtained with the satellite observing in a spinning mode, surveying a large fraction of the sky every day. Multifrequency observations of PKS 1510-089 are strongly encouraged.

 

REM observations confirm a rapid outburst of the blazar 3C 273

ATel #2382; F. D'Ammando (Univ. Tor Vergata, INAF-IASF Roma), D. Fugazza (INAF-OA Brera), S. Covino (INAF-OA Brera), E. Molinari (INAF-OA Brera), I. Donnarumma (INAF-IASF Roma), P. Giommi (ASI/ASDC), A. Giuliani (INAF-IASF Milano), F. Longo (INFN Trieste), E. Pian (SNS Pisa, INAF-OA Trieste), C. M. Raiteri (INAF/OA Torino), P. Romano (INAF-IASF Palermo), M. Tavani (INAF-IASF Roma), A. Treves (Univ. dell'Insubria), S. Vercellone (INAF-IASF Palermo), M. Villata (INAF/OA Torino)
on 12 Jan 2010; 11:08 UT
Distributed as an Instant Email Notice (Request for Observations)
Password Certification: Filippo D'Ammando (filippo.dammando@iasf-roma.inaf.it)

Subjects: Infra-Red, Optical, AGN

The AGILE satellite detected a significant gamma-ray flare from 3C 273 between 2010-01-06 16:50 UT and 2010-01-08 07:50 UT (ATel #2376). The robotic 60-cm REM telescope located at La Silla (Chile), following a periodical monitoring program, observed automatically the field of the blazar 3C 273 in the first part of January 2010. Optical images were obtained using ROSS on 2010 January 1, 7, 8, 9 and 10 in the V, R, and I bands. Infrared observations were performed in the J and H bands using REMIR on 2010 January 1, 6, 7, 9 and 10. Preliminary results are reported in the following table.
Date-Obs V_mag R_mag I_mag J_mag H_mag
01/01/10 12.79 +/- 0.04 12.56 +/- 0.03 12.14 +/- 0.03 11.58 +/- 0.02 10.80 +/- 0.02
06/01/10 12.87 +/- 0.08 12.73 +/- 0.05 12.11 +/- 0.02 11.53 +/- 0.03 10.66 +/- 0.02
07/01/10 12.46 +/- 0.04 12.26 +/- 0.03 11.63 +/- 0.03 10.92 +/- 0.02 10.13 +/- 0.02
08/01/10 12.83 +/- 0.04 12.60 +/- 0.02 12.13 +/- 0.02 - -
09/01/10 12.77 +/- 0.04 12.55 +/- 0.03 12.10 +/- 0.03 11.51 +/- 0.02 10.76 +/- 0.02
10/01/10 12.78 +/- 0.03 12.55 +/- 0.03 12.08 +/- 0.03 11.52 +/- 0.02 10.75 +/- 0.02
REM observations confirm a rapid increase in the source flux of about 0.4 magnitudes in V and R bands, and 0.5 magnitudes in I, J and H bands in 2010 January 7 with respect to the observations of January 6, with a decrease in January 8-9 at the same level observed in January 1. We plan to keep monitoring the source with REM until the end of January 2010.

 

AGILE detection of a gamma-ray flare from the blazar 3C 273

ATel #2376; L. Pacciani (INAF/IASF-Rm), F. Verrecchia (ASDC), I. Donnarumma (INAF/IASF-Rm), C. Pittori (ASDC), M. Tavani (INAF/IASF-Rm), A. Bulgarelli, F. Gianotti, M. Trifoglio (INAF/IASF-Bo),E. Striani (Univ. Roma Tor Vergata and INFN Roma), S. Vercellone (INAF/IASF-Pa), F. D'Ammando (Univ. Roma Tor Vergata and INAF/IASF-Rm), E. Del Monte, Y. Evangelista, M. Feroci, F. Lazzarotto, P. Soffitta, E. Costa, I. Lapshov, M. Rapisarda, A. Argan, G. Piano, G. Pucella, S. Sabatini, A. Trois, V. Vittorini (INAF/IASF-Rm), F. Fuschino, M. Galli, C. Labanti, M. Marisaldi, G. Di Cocco (INAF/IASF-Bo), A. Chen, A. Giuliani, S. Mereghetti, P. Caraveo, F. Perotti (INAF/IASF-Mi), A. Pellizzoni, M. Pilia (INAF/OA-Cagliari), G. Barbiellini, F. Longo, E. Moretti, E. Vallazza (INFN Trieste), A. Morselli, P. Picozza (INFN and Univ. RomaTor Vergata), M. Prest (Universita` dell'Insubria), P. Lipari, D. Zanello (INFN and Univ. Roma Sapienza), P.W. Cattaneo, A. Rappoldi (INFN Pavia), F. Lucarelli, P. Santolamazza, S. Colafrancesco, P. Giommi (ASDC), L. Salotti (ASI)
on 8 Jan 2010; 19:02 UT
Distributed as an Instant Email Notice (Request for Observations)
Password Certification: Donnarumma Immacolata (immacolata.donnarumma@iasf-roma.inaf.it)

Subjects: Gamma Ray, Request for Observations, AGN, Quasars
Referred to by ATel #: 2382

AGILE is detecting significant gamma-ray emission above 100 MeV from a source positionally consistent with the the blazar 3C 273. Integrating from 2010-01-06 16:50 UT to 2010-01-08 07:50 UT, a quicklook maximum likelihood analysis yields a detection of 3C 273 at a significance level of about 5.0 sigma, and flux F = (450 +/- 140)e-8 ph/cm2/sec (E > 100 MeV). The most recent gamma-ray detection of significant emission from 3C 273 was reported by Fermi/LAT (ATel#2200) in September 2009, at a level comparable with our detection. The AGILE detection was obtained with the satellite observing in a spinning mode, surveying a large fraction of the sky every day. Multifrequency observations of 3C 273 are encouraged.

 

AGILE Detection of AGL J1023-3738, a new high-Galactic latitude unidentified source

ATel #2361; E. Striani (Univ. Roma Tor Vergata and INFN Roma), M. Tavani (INAF/IASF-Rm), A. Bulgarelli, F. Gianotti, M. Trifoglio (INAF/IASF-Bo), S. Vercellone (INAF/IASF-Pa), I. Donnarumma (INAF/IASF-Rm), F. D'Ammando (Univ. Roma Tor Vergata and INAF/IASF-Rm), E. Del Monte, Y. Evangelista, M. Feroci, F. Lazzarotto, L. Pacciani, P. Soffitta, E. Costa, I. Lapshov, M. Rapisarda, A. Argan, G. Piano, G. Pucella, S. Sabatini, A. Trois, V. Vittorini (INAF/IASF-Rm), F. Fuschino, M. Galli, C. Labanti, M. Marisaldi, G. Di Cocco (INAF/IASF-Bo), A. Chen, A. Giuliani, S. Mereghetti, P. Caraveo, F. Perotti (INAF/IASF-Mi), A. Pellizzoni, M. Pilia (INAF/OA-Cagliari), G. Barbiellini, F. Longo, E. Moretti, E. Vallazza (INFN Trieste), A. Morselli, P. Picozza (INFN and Univ. RomaTor Vergata), M. Prest (Universita` dell'Insubria), P. Lipari, D. Zanello (INFN and Univ. Roma Sapienza), P.W. Cattaneo, A. Rappoldi (INFN Pavia), C. Pittori, F. Verrecchia, P. Santolamazza, S. Colafrancesco, P. Giommi (ASDC), L. Salotti (ASI)
on 28 Dec 2009; 18:47 UT
Distributed as an Instant Email Notice (Request for Observations)
Password Certification: Marco Tavani (tavani@iasf-roma.inaf.it)

Subjects: Gamma Ray, Transients

AGILE detected intense gamma-ray emission above 100 MeV from a new unidentified source at high Galactic latitudes (AGL J1023-3738), with Galactic coordinates (l, b) = (273.1, 16.5) +/- 0.7 (95% stat. confidence level error box radius). Integrating from 2009-12-25 22:30 UT to 2009-12-27 22:10 UT, a maximum likelihood analysis yields a detection at a significance level larger than 5 sigma, and a flux F = (300+/-100)10-8 ph/cm2/s (E > 100 MeV). The source is still detectable with a significance level above 4 sigma for an integration between 2009-12-26 16:00 UT and 2009-12-28 10:00 UT. No extragalactic or Galactic catalogued source is known within the error box of AGL J1023-3738. This measurement was obtained with AGILE observing a large portion of the sky in a spinning mode. Multifrequency observations of the AGL J1023-3738 error box are strongly encouraged.

 

AGILE detection of a gamma-ray flare from the blazar PKS 1222+216

ATel #2348; F. Verrecchia (ASDC), E. Striani (Univ. Roma Tor Vergata and INFN Roma), M. Tavani (INAF/IASF-Rm), C. Pittori, P. Santolamazza, F. Lucarelli (ASDC), S. Vercellone (INAF/IASF-Pa), F. D'Ammando (Univ. Roma Tor Vergata and INAF/IASF-Rm), I. Donnarumma, V. Vittorini, E. Del Monte, Y. Evangelista, M. Feroci, F. Lazzarotto, L. Pacciani, P. Soffitta, E. Costa, I. Lapshov, M. Rapisarda, A. Argan, G. Piano, G. Pucella, S. Sabatini, A. Trois (INAF/IASF-Rm), A. Bulgarelli, F. Gianotti, M. Trifoglio, F. Fuschino, M. Galli, C. Labanti, M. Marisaldi, G. Di Cocco (INAF/IASF-Bo), A. Chen, A. Giuliani, S. Mereghetti, P. Caraveo, F. Perotti (INAF/IASF-Mi), A. Pellizzoni, M. Pilia (INAF/OA-Cagliari), G. Barbiellini, F. Longo, E. Moretti, E. Vallazza (INFN Trieste), A. Morselli, P. Picozza (INFN and Univ. Roma Tor Vergata), M. Prest (Universita` dell'Insubria), P. Lipari, D. Zanello (INFN and Univ. Roma Sapienza), P.W. Cattaneo, A. Rappoldi (INFN Pavia), S. Colafrancesco, P. Giommi (ASDC), L. Salotti (ASI)
on 15 Dec 2009; 14:33 UT
Distributed as an Instant Email Notice (Request for Observations)
Password Certification: Carlotta Pittori (carlotta.pittori@asdc.asi.it)

Subjects: Gamma Ray, >GeV, Request for Observations, AGN, Quasars

AGILE is detecting a significant gamma-ray emission above 100 MeV from a source consistent with the position of the blazar PKS 1222+216.

Integrating from 2009-12-13 06:00 UT to 2009-12-15 06:00 UT, a quicklook maximum likelihood analysis of the AGILE-GRID data yields a detection at a significance level larger than 5 sigma and a source flux above 250e-8 ph/cm2/sec (E > 100 MeV).

An increased gamma-ray activity from a source consistent with the blazar PKS 1222+216 was previously reported by Fermi/LAT (ATel #2021) on April 16 2009, with a gamma-ray flux of (46+/-13)e-8 ph/cm2/sec (E > 100MeV), ten times higher than the average 6 months value. This blazar was also detected by EGRET (3EG J1224+2118), with an average flux of (14+/-2)e-8 ph/cm2/sec.

The AGILE/GRID detection was obtained while AGILE is observing the sky in a spinning mode, surveying a large fraction of the sky every day.

Multifrequency observations of the blazar PKS 1222+216 are strongly encouraged.

 

INTEGRAL/IBIS observation of the blazar 3C 454.3 during the decaying phase of the gamma-ray super-flare

ATel #2344; S. Vercellone (INAF/IASF-Pa), M. Fiocchi (INAF/IASF-Rm), E. Pian (SNS Pisa), M. Tavani, A. Bazzano, P. Ubertini (INAF/IASF-Rm), A. Argan, E. Costa, (INAF/IASF-Rm), F. D'Ammando (Univ. Roma Tor Vergata and INAF/IASF-Rm), E. Del Monte, I. Donnarumma, Y. Evangelista, M. Feroci, I. Lapshov, F. Lazzarotto, L. Pacciani, G. Piano, G. Pucella, M. Rapisarda, S. Sabatini, P. Soffitta (INAF/IASF-Rm), E. Striani (Univ. Roma Tor Vergata and INFN Roma), A. Trois, V. Vittorini (INAF/IASF-Rm), A. Bulgarelli, G. Di Cocco, F. Fuschino, M. Galli, F. Gianotti, C. Labanti, M. Marisaldi, M. Trifoglio (INAF/IASF-Bo), P. Caraveo, A. Chen, A. Giuliani, S. Mereghetti, F. Perotti (INAF/IASF-Mi), A. Pellizzoni, M. Pilia (INAF/OA-Cagliari), G. Barbiellini, F. Longo, E. Moretti, E. Vallazza (INFN Trieste), A. Morselli, P. Picozza (INFN and Univ. Roma Tor Vergata), M. Prest (Universita` dell'Insubria), P. Lipari, D. Zanello (INFN and Univ. Roma Sapienza), P.W. Cattaneo, A. Rappoldi (INFN Pavia), S. Colafrancesco, P. Giommi, C. Pittori, P. Santolamazza, F. Verrecchia (ASDC), L. Salotti (ASI)
on 11 Dec 2009; 16:48 UT
Password Certification: Stefano Vercellone (stefano@iasf-milano.inaf.it)

Subjects: X-ray, Gamma Ray, AGN, Quasars
Referred to by ATel #: 2345

The INTEGRAL satellite performed a Target of Opportunity observation of the blazar 3C 454.3 following the detection by the AGILE/GRID (ATel #2326) and by the Fermi/LAT (ATel #2328) of a gamma-ray super-flare above 100 MeV on 2009-12-02.

Integrating the data from 2009-12-06 16:41 UT to 2009-12-09 07:46 UT, for a net exposure of about 205 ks, we obtain a detection of the blazar with INTEGRAL/IBIS with a flux F(20-40 keV) = 13 mCrab (9.8E-11 erg/cm2/s), and a flux F(40-100 keV) = 16 mCrab (1.5E-10 erg/cm2/s). The 20-40 keV flux level shows a clearly decaying trend of the hard X-ray emission when compared with the flux levels observed by Swift/BAT (ATel #2330): 20 mCrab on 2009-12-01, 50 mCrab on 2009-12-03, followed by a steady flux level of 30 mCrab.

We kindly thank the INTEGRAL Team for promptly accepting and performing this observation.

 
 

AGILE detects an extraordinary gamma-ray activity from the FSRQ 3C 454.3

ATel #2326; E. Striani (Univ. Roma Tor Vergata and INFN Roma), S. Vercellone (INAF/IASF-Pa), F. Verrecchia, C. Pittori, P. Santolamazza (ASDC), M. Tavani (INAF/IASF-Rm), F. D'Ammando (Univ. Roma Tor Vergata and INAF/IASF-Rm), I. Donnarumma, V. Vittorini, E. Del Monte, Y. Evangelista, M. Feroci, F. Lazzarotto, L. Pacciani, P. Soffitta, E. Costa, I. Lapshov, M. Rapisarda, A. Argan, G. Piano, G. Pucella, S. Sabatini, A. Trois (INAF/IASF-Rm), A. Bulgarelli, F. Gianotti, M. Trifoglio, F. Fuschino, M. Galli, C. Labanti, M. Marisaldi, G. Di Cocco (INAF/IASF-Bo), A. Chen, A. Giuliani, S. Mereghetti, P. Caraveo, F. Perotti (INAF/IASF-Mi), A. Pellizzoni, M. Pilia (INAF/OA-Cagliari), G. Barbiellini, F. Longo, E. Moretti, E. Vallazza (INFN Trieste), A. Morselli, P. Picozza (INFN and Univ. Roma Tor Vergata), M. Prest (Universita` dell'Insubria), P. Lipari, D. Zanello (INFN and Univ. Roma Sapienza), P.W. Cattaneo, A. Rappoldi (INFN Pavia), S. Colafrancesco, P. Giommi,(ASDC), L. Salotti (ASI)
on 3 Dec 2009; 16:27 UT
Distributed as an Instant Email Notice (Request for Observations)
Password Certification: Stefano Vercellone (stefano@iasf-milano.inaf.it)

Subjects: Gamma Ray, >GeV, Request for Observations, AGN, Quasars

The AGILE Gamma-Ray Imaging Detector (GRID) has been detecting an extraordinary intense gamma-ray emission above 100 MeV from the flat spectrum radio quasar 3C 454.3.

Integrating from 2009-12-02 06:30 UT to 2009-12-03 08:30 UT, a quick-look maximum likelihood analysis yields a source flux of about (1800 +/- 400)e-8 ph/cm2/sec (E > 100 MeV). This flux value greatly exceeds the value reported by AGILE in ATel #2322, showing a rapid increase (about 80%) of the gamma-ray flux of 3C 454.3 in the last 24 hours.

An optical brightening (R band) during the period between November 21 and December 1-2 is also reported by the GASP-WEBT in ATel #2325.

The AGILE/GRID detection was obtained while AGILE is observing in spinning mode, surveying a large fraction of the sky each day. Multifrequency observations of the source are strongly encouraged.

 

 

AGILE detects intense and prolonged gamma-ray activity from the FSRQ 3C 454.3

ATel #2322; E. Striani (Univ. Roma Tor Vergata and INFN Roma), S. Vercellone (INAF/IASF-Pa), F. Verrecchia, C. Pittori, P. Santolamazza (ASDC), M. Tavani (INAF/IASF-Rm), F. D'Ammando (Univ. Roma Tor Vergata and INAF/IASF-Rm), I. Donnarumma, V. Vittorini, E. Del Monte, Y. Evangelista, M. Feroci, F. Lazzarotto, L. Pacciani, P. Soffitta, E. Costa, I. Lapshov, M. Rapisarda, A. Argan, G. Piano, G. Pucella, S. Sabatini, A. Trois (INAF/IASF-Rm), A. Bulgarelli, F. Gianotti, M. Trifoglio, F. Fuschino, M. Galli, C. Labanti, M. Marisaldi, G. Di Cocco (INAF/IASF-Bo), A. Chen, A. Giuliani, S. Mereghetti, P. Caraveo, F. Perotti (INAF/IASF-Mi), A. Pellizzoni, M. Pilia (INAF/OA-Cagliari), G. Barbiellini, F. Longo, E. Moretti, E. Vallazza (INFN Trieste), A. Morselli, P. Picozza (INFN and Univ. Roma Tor Vergata), M. Prest (Universita` dell'Insubria), P. Lipari, D. Zanello (INFN and Univ. Roma Sapienza), P.W. Cattaneo, A. Rappoldi (INFN Pavia), S. Colafrancesco, P. Giommi,(ASDC), L. Salotti (ASI)


on 2 Dec 2009; 16:36 UT

Distributed as an Instant Email Notice (Request for Observations)
Password Certification: Stefano Vercellone (stefano@iasf-milano.inaf.it)

Subjects: Gamma Ray, >GeV, Request for Observations, AGN, Quasars
The AGILE Gamma-Ray Imaging Detector (GRID) has been detecting prolonged flaring gamma-ray emission above 100 MeV from the flat spectrum radio quasar 3C 454.3. Integrating from 2009-11-26 01:00UT to 2009-12-02 08:30UT, a quick-look maximum likelihood analysis yields a source flux of about 700e-8 ph/cm2/sec (E > 100 MeV), with a peak in the last 48 hours of the order of 1000e-8 ph/cm2/sec (E > 100 MeV). This source behavior is different from what previously reported both by AGILE on a 2-year time-span (ATel #1160; ATel #1167; ATel #1278; ATel #1300; ATel #1545; ATel #1581; ATel #1592; ATel #1628; see also Vercellone et al., 2008, ApJL, 676, 13; Vercellone et al., 2009, ApJ, 690, 1018; Donnarumma et al., 2009, ApJ, in press [ArXiv:0910.4883]), and by Fermi during its first year (ATel #1628; ATel #2200). It is similar to what reported in (Abdo et al., 2009, ApJ, 699, 817) when the source exhibited a flare at a flux level of about 1200e-8 ph/cm2/sec (E > 100 MeV), and its flux remained above 700e-8 ph/cm2/sec (E > 100 MeV) for about 1 week. The AGILE/GRID detection was obtained while AGILE is observing in spinning mode, surveying a large fraction of the sky each day. Multifrequency observations of the source are encouraged.

 

 

AGILE confirms high gamma-ray state of GB6 B1310+4844

ATel #2310; A. Bulgarelli, F. Gianotti, M. Trifoglio (INAF/IASF-Bo), S. Vercellone (INAF/IASF-Pa), M. Tavani (INAF/IASF-Rm), E. Striani (Univ. Roma Tor Vergata and INFN Roma), F. Verrecchia, C. Pittori, P. Santolamazza (ASDC), F. D'Ammando (Univ. Roma Tor Vergata and INAF/IASF-Rm), I. Donnarumma (INAF/IASF-Rm), V. Vittorini, E. Del Monte, Y. Evangelista, M. Feroci, F. Lazzarotto, L. Pacciani, P. Soffitta, E. Costa, I. Lapshov, M. Rapisarda, A. Argan, G. Piano, G. Pucella, S. Sabatini, A. Trois (INAF/IASF-Rm), F. Fuschino, M. Galli, C. Labanti, M. Marisaldi, G. Di Cocco (INAF/IASF-Bo), A. Chen, A. Giuliani, S. Mereghetti, P. Caraveo, F. Perotti (INAF/IASF-Mi), A. Pellizzoni, M. Pilia (INAF/OA-Cagliari), G. Barbiellini, F. Longo, E. Moretti, E. Vallazza (INFN Trieste), A. Morselli, P. Picozza (INFN and Univ. Roma Tor Vergata), M. Prest (Universita` dell'Insubria), P. Lipari, D. Zanello (INFN and Univ. Roma Sapienza), P.W. Cattaneo, A. Rappoldi (INFN Pavia), S. Colafrancesco, P. Giommi,(ASDC), L. Salotti (ASI)
on 23 Nov 2009; 13:04 UT
Password Certification: Stefano Vercellone (stefano@iasf-milano.inaf.it)

Subjects: Gamma Ray, >GeV, AGN, Quasars

The AGILE Gamma-Ray Imaging Detector (GRID) detected significant gamma-ray emission above 100 MeV from a source consistent with the blazar GB6 B1310+4844, recently reported in a high gamma-ray state by Fermi/LAT on Nov. 18 2009 (Sokolovsky et al., ATel #2306).

Integrating from 2009-11-20 17:00 UT to 2009-11-22 17:00 UT, a maximum likelihood analysis shows a detection at a significance level above 4.7 sigma, with a source flux above 100 e-8 ph/cm2/sec (E > 100 MeV), confirming the current high gamma-ray state of the source.

A maximum likelihood analysis from 2009-11-18 17:00 UT to 2009-11-22 17:00 UT shows an AGILE detection at a significance level above 6 sigma.

The AGILE/GRID detection was obtained while AGILE is observing in spinning mode, surveying a large fraction of the sky each day.

 

 

AGILE detection of the gamma-ray blazar PKS 1830-211

ATel #2242; E. Striani (Univ. Roma Tor Vergata), F. Verrecchia, C. Pittori (ASDC), M. Tavani (INAF/IASF-Rm), F. D'Ammando (Univ. Roma Tor Vergata and INAF/IASF-Rm), I. Donnarumma (INAF/IASF-Rm), S. Vercellone (INAF/IASF-Pa), V. Vittorini, E. Del Monte, Y. Evangelista, M. Feroci, F. Lazzarotto, L. Pacciani, P. Soffitta, E. Costa, I. Lapshov, M. Rapisarda, A. Argan, G. Piano, G. Pucella, S. Sabatini, A. Trois (INAF/IASF-Rm), A. Bulgarelli, F. Fuschino, M. Galli, F. Gianotti, C. Labanti, M. Marisaldi, M. Trifoglio, G. Di Cocco (INAF/IASF-Bo), A. Chen, A. Giuliani, S. Mereghetti, P. Caraveo, F. Perotti (INAF/IASF-Mi), A. Pellizzoni, M. Pilia (INAF/OA-Cagliari), G. Barbiellini, F. Longo, E. Moretti, E. Vallazza (INFN Trieste), A. Morselli, P. Picozza (INFN and Univ. Roma Tor Vergata), M. Prest (Universita` dell'Insubria), P. Lipari, D. Zanello (INFN and Univ. Roma Sapienza), P.W. Cattaneo, A. Rappoldi (INFN Pavia), P. Santolamazza, S. Colafrancesco, P. Giommi,(ASDC), L. Salotti (ASI)
on 14 Oct 2009; 18:33 UT
Password Certification: Carlotta Pittori (carlotta.pittori@asdc.asi.it)

Subjects: Gamma Ray, >GeV, AGN, Quasars

During the current AGILE pointing centered near the Galactic Center, the AGILE Gamma-Ray Imaging Detector (GRID) has detected significant gamma-ray emission above 100 MeV from a gamma-ray source positionally consistent with the blazar PKS 1830-211.

Integrating from 2009-10-12 00:03 UT to to 2009-10-13 04:57 UT, a maximum likelihood analysis shows a detection at a significance level above 5 sigma, with a source flux reaching a gamma-ray flux of (160+/-50) e-8 ph/cm2/sec above 100 MeV.

By integrating on a longer time-span, between 2009-10-05 04:50 UT and 2009-10-11 03:39 UT, AGILE/GRID detects PKS 1830-211 at a significance level above 3 sigma with an average flux of about 40 e-8 ph/cm2/sec.

There is evidence of significant spectral variability above 100 MeV during the last 7 days. We strongly encourage multi-frequency observations of PKS 1830-211, while AGILE will keep pointing the Galactic center until 2009-10-15 12:00 UT.

 

 

 


SuperAGILE detection of a type I X-ray burst from a position consistent with HETE J1900.1-2455

ATel #2238; Y. Evangelista, E. Del Monte, M. Feroci, L. Pacciani, E. Costa, I. Donnarumma, I. Lapshov, F. Lazzarotto, M. Rapisarda, P. Soffitta, A. Argan, A. Trois , M. Tavani, G. Piano, G. Pucella, F. D'Ammando, S. Sabatini, E. Striani, V. Vittorini (INAF/IASF Roma), A. Bulgarelli, F. Gianotti, M. Trifoglio, G. Di Cocco, C. Labanti, F. Fuschino, M. Marisaldi, M. Galli (INAF/IASF Bologna), A. Chen, A. Giuliani, S. Mereghetti, F. Perotti, P. Caraveo (INAF/IASF Milano), A. Pellizzoni, M. Pilia (OAC/INAF Cagliari), S. Vercellone (INAF/IASF Palermo), G. Barbiellini, F. Longo, E. Moretti, E. Vallazza (INFN Trieste), P. Picozza, A. Morselli (INFN Roma-2), M. Prest (Universita` dell'Insubria), P. Lipari, D. Zanello (INFN Roma-1), A. Rappoldi (INFN Pavia) and C. Pittori, F. Verrecchia, P. Santolamazza, P. Giommi (ASDC) and L. Salotti (ASI)
on 9 Oct 2009; 22:05 UT
Password Certification: Marco Feroci (marco.feroci@iasf-roma.inaf.it)

Subjects: X-ray, Request for Observations, Binaries, Neutron Stars, Transients

On 9 October 2009 02:57:43 UT SuperAGILE detected a type I X-ray burst from a sky position consistent with the accreting millisecond pulsar HETE J1900.1-2455. The burst was significantly detected only at energies below 28 keV, as typical of type I X-ray bursts in SuperAGILE, due to their soft energy spectrum. The burst profile is double-peaked, with a total duration of about 13 s, similar to previous bursts from this source (e.g., Suzuki et al. PASJ 2007 or Falanga et al. A&A 2008). Using the data in the energy range 17-25 keV, we measure an average burst flux of 1.3e-8 erg/cm2/s (under the assumption of a Crab-like energy spectrum). The latest notified X-ray burst from this source was on April 2009 (Watts et al., ATel #2004). The persistent emission from HETE J1900.1-2455 is currently detected by SuperAGILE at an average flux level of about 50 mCrab (20-60 keV), on daily integrations. The source localization by SuperAGILE is composed by two one-dimensional projections. One of the two projections of the detected burst position is unambiguously consistent with the position of HETE J1900.1-2455. The other 1D image shows a potential ambiguity due to a secondary peak, possibly due to a statistical fluctuation. In the hypothesis of a source identification with this secondary peak, the burst localization would be (RA,Dec) =(294.3635, -23.7796), with an error radius of 6 arcmin. This position corresponds to Galactic coordinates (l,b)=(15.845,-20.260) and it has no known source counterpart yet. We however consider the association with HETE J1900.1-2455 more likely.

 

 

Swift follow-up observations of the blazar PKS 1510-089 after a high optical flare

ATel #2047; F. D'Ammando (Univ. Tor Vergata, INAF-IASF Roma), H. Krimm (CRESST/GSFC/USRA), P. Romano, S. Vercellone (INAF-IASF Palermo)
on 15 May 2009; 21:37 UT
Password Certification: Pat Romano (romano@ifc.inaf.it)

Subjects: X-ray, Gamma Ray, AGN

Following the extraordinary optical brightness level of the blazar PKS 1510-089 on May 08.9 (Larionov et al., ATel #2045), we report on the analysis of Swift data obtained immediately after the optical flare. The Swift/BAT hard X-ray transient monitor detected an outburst in PKS 1510-089 in the 15-50 keV energy band. On 2009 May 10 (MJD 54961) the count rate was 0.009 +/- 0.005 cts/s/cm^2 (40 mCrab). The source then declined to background on May 11, before rising again to 0.003 +/- 0.001 cts/s/cm^2 (14 mCrab) on May 13. It has remained at nearly the same rate since then. This is roughly the same brightness as was reported in March 2009 (Krimm et al, ATel #1963). Target of Opportunity observations with Swift/XRT were obtained on May 11, 12, 13, and 14. The first short (1.4 ks) Swift/XRT observation is strongly affected by the presence of a hot column at the center of the PSF. The spectra of the Swift/XRT following observations (4 to 5 ks each on-source time) can be fit (0.3-10 keV energy range) with an absorbed power-law model with a column density consistent with the Galactic one in the direction of the source (n_H = 6.89E20 cm^-2, Kalberla et al. 2005) and a photon index of 1.34+/-0.09, 1.51+/-0.10 and 1.41+/-0.10, respectively. The corresponding unabsorbed 0.3-10 keV fluxes are 1.3E-11, 1.0E-11, and 1.0E-11 erg cm^-2 s^-1. The X-ray flux confirms the high activity of the source at the beginning of the Swift/XRT observations. We thank Neil Gehrels and the Swift Team for making these observations possible, in particular the duty scientists and science planners.

 

 

Swift detection of an X-ray transient possibly associated with IGR J17354-3255

ATel #2019; S. Vercellone (INAF-IASF Palermo), F. D'Ammando, E. Striani, M. Tavani (INAF-IASF Roma), S. Sabatini (INFN Roma-2), A. Bulgarelli, F. Gianotti, M. Trifoglio (INAF-IASF Bologna), M. Feroci, F. Lazzarotto, E. Del Monte (INAF-IASF Roma), C. Pittori, F. Verrecchia (ASDC), A. Pellizzoni, M. Pilia (INAF-OACagliari), A. Chen, A. Giuliani (INAF-IASF Milano), G. Piano, G. Pucella, V. Vittorini, E. Costa, I. Donnarumma, L. Pacciani, P. Soffitta, Y. Evangelista, I. Lapshov, M. Rapisarda, A. Argan, A. Trois, G. De Paris (INAF-IASF Roma), M. Marisaldi, G. Di Cocco, C. Labanti, F. Fuschino, M. Galli (INAF-IASF Bologna), P. Caraveo, S. Mereghetti, F. Perotti, M. Fiorini, A. Zambra (INAF-IASF Milano), G. Barbiellini, F. Longo, E. Moretti, E. Vallazza (INFN Trieste), P. Picozza, A. Morselli (INFN Roma-2), M. Prest (Universita` dell'Insubria), P. Lipari, D. Zanello (INFN Roma-1), P. Cattaneo (INFN Pavia), Rappoldi (INFN Pavia), P. Santolamazza, S. Colafrancesco, P. Giommi (ASDC), L. Salotti (ASI), P. Romano (INAF-IASF Palermo), D.N. Burrows (PSU), N. Gehrels (GSFC)
on 17 Apr 2009; 21:11 UT
Distributed as an Instant Email Notice (Request for Observations)
Password Certification: Stefano Vercellone (stefano@iasf-milano.inaf.it)

Subjects: X-ray, Request for Observations, Transients
Referred to by ATel #: 2022

Following the AGILE/GRID detection of the candidate gamma-ray transient AGL J1734-3310 (Bulgarelli et al., ATel #2017), whose position is consistent with the INTEGRAL unidentified source IGR J17354-3255 (Kuulkers et al., ATel #874), we performed a Swift target of opportunity observation on the INTEGRAL source.

The field was observed with Swift/XRT for 5.3 ks from 2009-04-17 01:08:59 to 2009-04-17 07:57:56 UT. Within the 4 arcmin INTEGRAL error circle we detected two sources.

Source #1 (RA, DEC) = (17 35 27.16, -32 55 48.9) with an estimated error radius of 3.7 arcsec (90% c.l.). The source was detected with a mean count rate of CR = (1.14 +/- 0.07)E-01 counts/s. Throughout the observation, the count rate shows an increasing trend from 0.016 to 0.15 counts/s, hence displaying a dynamic range of the order of ten in about seven hours. The spectrum can be fit (reduced chi^2/dof = 1.06/15) with an absorbed blackbody with a temperature kT = 1.4 (-0.1, +0.3) keV and a high absorption column of NH = (5+/-2)E22 cm^-2, in excess of the Galactic one (1.2E22 cm^-2). The observed (unabsorbed) 0.3-10 keV flux is 1.1E-11 (1.6E-11) erg/cm^2/s.

Source #2 (RA, DEC) = (17 35 18.32, -32 54 22.9) with an estimated error radius of 5.0 arcsec (90% c.l.). The source was detected with a mean count rate of CR=(4.6 +/- 1.3)E-03 counts/s.

Analysis of archival Swift/XRT data (4.4 ks, from 2008-03-11 01:05:20 to 2008-03-11 10:52:57 UT), only reveals source #2 at a count rate of CR = (4.5 +/- 1.3)E-3 count/s, consistent with the one obtained during the most recent observation. Thus, we suggest a persistent nature for source #2, and propose source #1 as a possible counterpart of IGR J17354-3255. Furthermore, we can place a 3 sigma upper limit on source #1 at 4.7E-3 counts/s on 2008-03-11.

 

 

The candidate gamma-ray transient AGL J1734-3310 in the Galactic plane.

ATel #2017; A. Bulgarelli, F. Gianotti, M. Trifoglio (INAF-IASF Bologna), E. Striani, M. Tavani (INAF-IASF Roma), S. Sabatini (INFN Roma-2), S. Vercellone (INAF-IASF Palermo), M. Feroci, F. Lazzarotto, E. Del Monte (INAF-IASF Roma), C. Pittori, F. Verrecchia (ASDC), A. Pellizzoni, M. Pilia (INAF-OACagliari), A. Chen, A. Giuliani (INAF-IASF Milano), F. D'Ammando, G. Piano, G. Pucella, V. Vittorini, E. Costa, I. Donnarumma, L. Pacciani, P. Soffitta, Y. Evangelista, I. Lapshov, M. Rapisarda, A. Argan, A. Trois, G. De Paris (INAF-IASF Roma), M. Marisaldi, G. Di Cocco, C. Labanti, F. Fuschino, M. Galli (INAF-IASF Bologna), P. Caraveo, S. Mereghetti, F. Perotti, M. Fiorini, A. Zambra (INAF-IASF Milano), G. Barbiellini, F. Longo, E. Moretti, E. Vallazza (INFN Trieste), P. Picozza, A. Morselli (INFN Roma-2), M. Prest (Universita` dell'Insubria), P. Lipari, D. Zanello (INFN Roma-1), P. Cattaneo (INFN Pavia), P. Santolamazza, S. Colafrancesco, P. Giommi (ASDC), L. Salotti (ASI).
on 17 Apr 2009; 18:23 UT
Distributed as an Instant Email Notice (Request for Observations)
Password Certification: Stefano Vercellone (stefano@iasf-milano.inaf.it)

Subjects: Gamma Ray, Request for Observations, Transients
Referred to by ATel #: 2019, 2022

During the current AGILE pointing centered near the Aquila field the Gamma-Ray Imaging Detector (GRID) detected a possible candidate gamma-ray transient.

Integrating from 2009-04-14 00:00 UT to 2009-04-15 00:00 UT, a preliminary maximum likelihood analysis for energies above 100 MeV shows a detection at a significance level above 4.5 sigma and a flux excess of about 350e-8 +/- 100 ph/cm2/s. The source is not detected at energies above 400 MeV.

The source positional error box is centered at Galactic coordinates l = 355.17 deg, b = -0.28 deg (R.A. = 17h 34m 44s, DEC = -33h 10m 38s ) and has a preliminary 1-day timescale 95% confidence radius of 0.65 degrees.

The candidate gamma-ray transient AGL J1734-3310 appears to be consistent in position with 1AGL J1736-3235 and also with the INTEGRAL unidentified source IGR J17354-3255.

A preliminary analysis of the Super-AGILE data over the same time period and the same sky region does not show any counterpart in the 20-60 keV energy range, with a 3-sigma upper limit of 40 mCrab on the average flux.

We strongly encourage multi-frequency observations of the AGL J1734-3310 field.

 

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AGILE detection of a gamma-ray re-brightening of the blazar PKS 1510-089

ATel #1976; S. Vercellone (INAF-IASF Palermo), F. D'Ammando, G. Pucella, M. Tavani, I. Donnarumma, L. Pacciani (INAF-IASF Roma), A. Bulgarelli, M. Marisaldi, F. Gianotti, M. Trifoglio (INAF-IASF Bologna), C. Pittori, F. Verrecchia (ASDC), A. Chen, A. Giuliani (INAF-IASF Milano), G. Piano, V. Vittorini, E. Costa, M. Feroci, E. Del Monte, F. Lazzarotto, P. Soffitta, Y. Evangelista, I. Lapshov, M. Rapisarda, A. Argan, A. Trois, G. De Paris (INAF-IASF Roma), G. Di Cocco, C. Labanti, F. Fuschino, M. Galli (INAF-IASF Bologna), P. Caraveo, S. Mereghetti, F. Perotti, M. Fiorini, A. Zambra (INAF-IASF Milano), A. Pellizzoni, M. Pilia (INAF-OA Cagliari), G. Barbiellini, F. Longo, E. Moretti, E. Vallazza (INFN Trieste), P. Picozza, A. Morselli, S. Sabatini (INFN Roma-2), M. Prest (Universita' dell'Insubria), P. Lipari, D. Zanello (INFN Roma-1), P.W. Cattaneo, A. Rappoldi (INFN Pavia), P. Santolamazza, S. Colafrancesco, P. Giommi (ASDC), L. Salotti (ASI).
on 19 Mar 2009; 12:07 UT
Distributed as an Instant Email Notice (Transients)
Password Certification: Stefano Vercellone (stefano@iasf-milano.inaf.it)

Subjects: Gamma Ray, Request for Observations, AGN, Quasars

The Flat Spectrum Radio Quasar PKS 1510-089, shows a new significant re-brightening above 100 MeV following the previous period of intense gamma-ray activity (see Pucella et al., ATel #1968; D'Ammando et al., ATel #1957).

A maximum likelihood analysis of 1AGL J1511-0809 (PKS 1510-089) data obtained between 2009-03-18 05:45 UT and 2009-03-19 05:33 UT for photon energies above 100 MeV yields a detection significance of above 7 sigma with a source flux of about 400 x 10^-8 ph cm^-2 s^-1. This value represents an increase of more than a factor of 3 within 24 hours compared with the gamma-ray flux level detected during the previous three days (between 2009-03-15 06:21 UT and 2009-03-18 05:45 UT), when the average flux was about 120 x 10^-8 ph cm^-2 s^-1.

We strongly encourage multi-frequency observations of PKS 1510-089 during this remarkable gamma-ray flaring state. The AGILE monitoring of the field containing this source is currently scheduled to continue until 2009-03-25.

 

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AGILE detection of a persistent and very intense gamma-ray flaring state of the blazar PKS 1510-089

ATel #1968; G. Pucella, F. D'Ammando, M. Tavani, E. Del Monte (INAF-IASF Roma), M. Marisaldi, F. Gianotti, M. Trifoglio, A. Bulgarelli (INAF-IASF Bologna), C. Pittori, F. Verrecchia (ASDC), S. Vercellone (INAF-IASF Palermo), A. Chen, A. Giuliani (INAF-IASF Milano), G. Piano, V. Vittorini, E. Costa, M. Feroci, I. Donnarumma, L. Pacciani, F. Lazzarotto, P. Soffitta, Y. Evangelista, I. Lapshov, M. Rapisarda, A. Argan, A. Trois, G. De Paris (INAF-IASF Roma), G. Di Cocco, C. Labanti, F. Fuschino, M. Galli (INAF-IASF Bologna), P. Caraveo, S. Mereghetti, F. Perotti, M. Fiorini, A. Zambra (INAF-IASF Milano), A. Pellizzoni, M. Pilia (INAF-OACagliari), G. Barbiellini, F. Longo, E. Moretti, E. Vallazza (INFN Trieste), P. Picozza, A. Morselli, S. Sabatini (INFN Roma-2), M. Prest (Universita` dell'Insubria), P. Lipari, D. Zanello (INFN Roma-1), P. Cattaneo (INFN Pavia), P. Santolamazza, S. Colafrancesco, P. Giommi (ASDC), L. Salotti (ASI).
on 13 Mar 2009; 13:00 UT
Distributed as an Instant Email Notice (Request for Observations)
Password Certification: Marco Tavani (tavani@iasf-roma.inaf.it)

Subjects: Gamma Ray, Request for Observations, AGN, Quasars

The gamma-ray source 1AGL J1511-0809, positionally consistent with the Flat Spectrum Radio Quasar PKS 1510-089, continues to show significant and very intense gamma-ray emission above 100 MeV (see D'Ammando et al., ATel #1957).

A maximum likelihood analysis of the AGILE-GRID data obtained between 2009-03-12 07:00 UT and 2009-03-13 05:00 UT for photon energies above 100 MeV results in a detection significance of above 9 sigma with a source flux in excess of above 400 x 10^-8 ph cm^-2 s^-1. The source positional error box obtained with a 1-day integration is centered at Galactic coordinates l = 351.21 deg, b = 40.12 deg with a radius of about 0.5 degrees.

A sky map above 100 MeV obtained during the March 12-13, 2009 period is available at the web sites http://agile.iasf-roma.inaf.it and http://agile.asdc.asi.it.

We strongly encourage multi-frequency observations of PKS 1510-089 during this remarkable gamma-ray flaring state. The AGILE monitoring of the field containing this source is currently scheduled to continue until 2009-03-25.

 

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AGILE detection of the flaring gamma-ray blazar PKS 1510-089

ATel #1957; F. D'Ammando (Univ. Tor Vergata and INAF-IASF Roma), S. Vercellone (INAF-IASF Palermo), M. Tavani, G. Pucella (INAF-IASF Roma), A. Chen, A. Giuliani (INAF-IASF Milano), A. Bulgarelli (INAF-IASF Bologna), G. Piano, V. Vittorini, E. Costa, M. Feroci, I. Donnarumma, L. Pacciani, E. Del Monte, F. Lazzarotto, P. Soffitta, Y. Evangelista, I. Lapshov, M. Rapisarda, A. Argan, A. Trois, G. De Paris (INAF-IASF Roma), M. Marisaldi, F. Gianotti, M. Trifoglio, G. Di Cocco, C. Labanti, F. Fuschino, M. Galli (INAF-IASF Bologna), P. Caraveo, S. Mereghetti, F. Perotti, M. Fiorini, A. Zambra (INAF-IASF Milano), A. Pellizzoni, M. Pilia (INAF-OACagliari), G. Barbiellini, F. Longo, E. Moretti, E. Vallazza (INFN Trieste), P. Picozza, A. Morselli, S. Sabatini (INFN Roma-2), M. Prest (Universita` dell'Insubria), P. Lipari, D. Zanello (INFN Roma-1), P. Cattaneo (INFN Pavia), C. Pittori, F. Verrecchia, P. Santolamazza, S. Colafrancesco, P. Giommi (ASDC), L. Salotti (ASI)
on 10 Mar 2009; 12:14 UT
Distributed as an Instant Email Notice (Request for Observations)
Password Certification: Marco Tavani (tavani@iasf-roma.inaf.it)

Subjects: Gamma Ray, Request for Observations, AGN, Quasars

During the current AGILE pointing centered near the Galactic Center the Gamma-Ray Imaging Detector (GRID) has detected significant gamma-ray emission above 100 MeV from a source positionally consistent with the blazar PKS 1510-089 (Position J2000.0: RA=15h12m50.5329s, DEC=-09d05m59.828s, redshift z = 0.361).

The source positional error box is centered at Galactic coordinates l = 351.15 deg, b = 40.02 deg with a radius of about 0.5 degrees and it is consistent with the source 1AGL J1511-0809 in the First AGILE Catalogue, identified with PKS 1510-089. This object is classified as a Flat Spectrum Radio Quasar (FSRQ) and was already known as an EGRET gamma-ray source, 3EG J1512-0849. Moreover this source was previously well detected during gamma-ray flares both by AGILE (Bulgarelli et al., ATel #1199; D'Ammando et al., ATel #1436; Pucella et al. 2008, A&A, 491, L21) and Fermi-LAT (Tramacere, ATel #1743, Ciprini et al., ATel #1897).

Preliminary analysis indicates that the source shows a significant increase of the gamma-ray activity starting on 8 March 2009 and a maximum likelihood analysis of the AGILE-GRID data obtained between 2009-03-08 14:00 UT and 2009-03-10 4:00 UT for photon energies above 100 MeV results in a detection significance of above 5 sigma with a source flux in excess of 200 x 10^-8 ph cm^-2 s^-1.

A preliminary analysis of the Super-AGILE data over the same time period and the same sky region does not show any counterpart in the 20-60 keV energy range, with a 3-sigma upper limit of 50 mCrab on the average flux. The AGILE monitoring of the field containing this source will continue until 2009-03-25. We strongly encourage multi-frequency observations of PKS 1510-089 during this gamma-ray high state.

 

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SuperAGILE detects a flare from the binary source 3A 0114+650

ATel #1917; L. Pacciani, E. Costa, E. Del Monte, I. Donnarumma, Y. Evangelista, M. Feroci, I. Lapshov, F. Lazzarotto, M. Rapisarda, P. Soffitta, A. Argan, A. Trois , M. Tavani, G. Piano, G. Pucella, F. D'Ammando, S. Sabatini, V. Vittorini (INAF/IASF Roma), A. Bulgarelli, F. Gianotti, M. Trifoglio, G. Di Cocco, C. Labanti, F. Fuschino, M. Marisaldi, M. Galli(INAF/IASF Bologna), A. Chen, S. Vercellone, A. Giuliani, S. Mereghetti, F. Perotti, F. Fornari, M. Fiorini, P. Caraveo (INAF/IASF Milano), A. Pellizzoni (OAC/INAF Cagliari), G.Barbiellini, F. Longo, E. Moretti, E. Vallazza (INFN Trieste), P. Picozza, A. Morselli (INFN Roma-2), M. Prest (Universita` dell'Insubria), P. Lipari, D. Zanello (INFN Roma-1), A. Rappoldi (INFN Pavia) and C. Pittori, F. Verrecchia, P.Santolamazza, B. Preger, P. Giommi (ASDC) and L. Salotti (ASI)
on 27 Jan 2009; 23:03 UT
Distributed as an Instant Email Notice (Request for Observations)
Password Certification: Marco Feroci (marco.feroci@iasf-roma.inaf.it)

Subjects: X-ray, Request for Observations, Binaries, Transients
Referred to by ATel #: 1918

During the current AGILE pointing at the Cygnus region, on 2009 January 27th SuperAGILE detected enhanced X-ray emission from the slowly-spinning high mass X-ray binary pulsar 3A 0114+650 (a.k.a. 4U 0114+650). The source was detected at an average flux level of 110 mCrab (20-60 keV energy range) for a time period of three AGILE orbits (approximately 5 hours total) between 08:50 and 13:50 UT. In the past days the source was not detected by SuperAGILE on the orbital timescale. An integration over the 24 hours preceding the flare provides only a marginal detection (3-sigma) at a flux level of 15-20 mCrab.

 

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AGILE detection of a possible rebrightening of the gamma-ray source AGL J2021+4032 in the Cygnus Region

ATel #1848; M. Tavani, G. Piano (INAF-IASF-Roma), A. Chen, A. Giuliani(INAF-IASF-Milano), A. Bulgarelli (INAF-IASF-Bologna), F. D'Ammando, G. Pucella, V. Vittorini, E. Costa, M. Feroci, I. Donnarumma, L. Pacciani, E. Del Monte, F. Lazzarotto, P. Soffitta, Y. Evangelista, I. Lapshov, M. Rapisarda, A. Argan, A. Trois, G. De Paris (INAF/IASF Roma), M. Marisaldi, F. Gianotti, M. Trifoglio, G. Di Cocco, C. Labanti, F. Fuschino, M. Galli (INAF/IASF Bologna), P. Caraveo, S. Mereghetti, A. Pellizzoni, S. Vercellone, F. Perotti, M. Fiorini, A. Zambra (INAF/IASF Milano), G. Barbiellini, F. Longo, E. Vallazza (INFN Trieste), P. Picozza, A. Morselli, S. Sabatini (INFN Roma-2), M. Prest (Universita` dell'Insubria), P. Lipari, D. Zanello (INFN Roma-1), P. Cattaneo (INFN Pavia), and D. Gasparrini, C. Pittori, F. Verrecchia, B. Preger, P. Santolamazza, S. Colafrancesco, P. Giommi (ASDC), L. Salotti (ASI)
on 17 Nov 2008; 20:19 UT
Distributed as an Instant Email Notice (Transients)
Password Certification: Marco Tavani (tavani@iasf-roma.inaf.it)

Subjects: Gamma Ray, Transients

During the current AGILE pointing centered near the Cygnus Region the Gamma-Ray Imaging Detector (GRID) has detected a source positionally consistent with the gamma-ray source previously reported in ATel#1585.

Integrating from 2008-11-16 14:33 UT to 2008-11-17 14:22 UT, a preliminary maximum likelihood analysis shows a detection at a significance level near 5 sigma, with a source flux more than two standard deviations above the mean flux reported in ATel#1585. The positional error box of the source AGL J2021+4032 (integrated over the total AGILE exposure of the field) is centered at Galactic coordinates l = 78.3 deg, b = 2.1 deg, and has a radius of about 0.2 degrees.

The AGILE monitoring of the field containing this source will continue until 2008-11-30 12:00 UT. We strongly encourage multi-frequency observations of the Cygnus field containing the gamma-ray source AGL J2021+4032.

 

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Swift Observation of the Microquasar Cygnus X-3

ATel #1830; G. Stratta (ASDC), F. D'Ammando, Y. Evangelista, M. Tavani (INAF/IASF Roma), N. Gehrels (NASA/GSFC), J. A. Kennea (PSU), G. Pucella, V. Vittorini, E. Costa, M. Feroci, I. Donnarumma, L. Pacciani, E. Del Monte, F. Lazzarotto, P. Soffitta, I. Lapshov, M. Rapisarda, S. Sabatini, G. Piano, A. Argan, A. Trois, G. De Paris (INAF/IASF Roma), M. Marisaldi, A. Bulgarelli, F. Gianotti, M. Trifoglio, G. Di Cocco, C. Labanti, F. Fuschino, M. Galli (INAF/IASF Bologna), A. Chen, P. Caraveo, A. Giuliani, S. Mereghetti, A. Pellizzoni, S. Vercellone, F. Perotti, M. Fiorini, A. Zambra (INAF/IASF Milano), G. Barbiellini, F. Longo, E. Vallazza (INFN Trieste), P. Picozza, A. Morselli (INFN Roma-2), M. Prest (Universita` dell'Insubria), P. Lipari, D. Zanello (INFN Roma-1), P.Cattaneo (INFN Pavia), and S. Cutini, C. Pittori, F. Verrecchia, B. Preger, P. Santolamazza, S. Colafrancesco, P. Giommi (ASDC), L. Salotti (ASI)
on 6 Nov 2008; 9:46 UT
Distributed as an Instant Email Notice (Request for Observations)
Password Certification: Marco Feroci (marco.feroci@iasf-roma.inaf.it)

Subjects: X-ray, Request for Observations, Binaries

SWIFT observed the Galactic microquasar Cygnus X-3 following the AGILE detection of the gamma-ray source AGL J2030+4043, whose position is consistent with that of Cygnus X-3 within the AGILE-GRID error box, as reported by Tavani et al. (ATel #1827). Very recently radio observations with the AMI Large Array showed an interesting low flux density of the source, which could precede a major radio flare (Pooley 2008, ATel #1828). SWIFT-XRT started the observation of Cygnus X-3 on 2008-11-04 at 04:44:28 UT. Data were taken in Windowed Timing mode for a total exposure of 5.9 ksec spanning a total of three orbits. During the first orbit (about 3 ksec) the 0.3-10 keV light curve shows an average count rate of 40-60 counts/s. During the second orbit, the count rate initially started at a value near 100 counts/s showing an increase by an additional 40% within a time scale of order of 500 sec. The third orbit shows an average count rate near 90 counts/s. The XRT spectrum in the 2.5-10 keV range during the first orbit can be fitted by an absorbed power law model plus an emission line (pcfabs*(power law + gaussian). Best fit parameters are N_H = (15 +/- 1)E22 cm^-2 with covering factor of 0.93, photon index = 4.0 +/- 0.1, E_line = 6.66 +/- 0.03 keV (sigma = 0.1 keV fixed). The average 2.5-10 keV flux is 3.6E-9 erg cm^-2 s^-1. During the second orbit, data can be fitted by the same model from 2.5 keV up to 9 keV, showing an excess at energies above 9 keV. The emission line is no more visible. Best fit parameters are N_H = (11 +/- 1)E22 cm^-2 and photon index = 3.6 +/- 0.1. The average 2.5-9 keV flux is 9.8E-9 erg cm^-2 s^-1. Compared to the previous SWIFT-XRT observations of Cygnus X-3, in which the 2-10 keV flux ranged between 0.78 and 20.2 E-9 (Moore et al. 2008, ATel #1655), the flux now observed is high with a rapid increase of the activity of the source during the second orbit. Further multifrequency observations of Cygnus X-3 are encouraged

AGILE detection of the gamma-ray source AGL J2030+4043

ATel #1827; M. Tavani, S. Sabatini, G. Piano, F. D'Ammando, G. Pucella, V. Vittorini, E. Costa, M. Feroci, I. Donnarumma, L. Pacciani, E. Del Monte, F. Lazzarotto, P. Soffitta, Y. Evangelista, I. Lapshov, M. Rapisarda, A. Argan, A. Trois, G. De Paris (INAF/IASF Roma), M. Marisaldi, A. Bulgarelli, F. Gianotti, M. Trifoglio, G. Di Cocco, C. Labanti, F. Fuschino, M. Galli (INAF/IASF Bologna), A. Chen, P. Caraveo, A. Giuliani, S. Mereghetti, A. Pellizzoni, S. Vercellone, F. Perotti, M. Fiorini, A. Zambra (INAF/IASF Milano), G. Barbiellini, F. Longo, E. Vallazza (INFN Trieste), P. Picozza, A. Morselli (INFN Roma-2), M. Prest (Universita` dell'Insubria), P. Lipari, D. Zanello (INFN Roma-1), P. Cattaneo (INFN Pavia), and S. Cutini, C. Pittori, F. Verrecchia, B. Preger, P. Santolamazza, S. Colafrancesco, P. Giommi (ASDC), L. Salotti (ASI)
on 4 Nov 2008; 19:29 UT
Distributed as an Instant Email Notice (Transients)
Password Certification: Marco Tavani (tavani@iasf-roma.inaf.it)

Subjects: Gamma Ray, Transients

During the current AGILE pointing centered near the Cygnus Region the Gamma-Ray Imaging Detector (GRID) detected a variable gamma-ray source.

Integrating from 2008-11-02 20:43 UT to 2008-11-03 20:32 UT, a preliminary maximum likelihood analysis shows a detection at a significance level above 4 sigma, with a source flux in excess of about 150e-8 ph/cm2/s for photon energies larger than 100 MeV.

The source positional error box is centered at Galactic coordinates l = 79.44 deg, b = 0.85 deg (R.A. = 20h 30m 31s, DEC = +40d 43m 09s) and has a preliminary 95% confidence radius of 0.9 degrees.

A preliminary analysis of the Super-AGILE data over the same time period and the same sky region does not show any counterpart in the 20-60 keV energy range, with a 3-sigma upper limit of 30 mCrab on the average flux.

We notice the presence in the AGILE-GRID error box of the prominent micro-quasar Cygnus X-3.

The AGILE monitoring of the field containing this source will continue until 2008-11-30 12:00 UT. We strongly encourage multi-frequency observations of the AGL J2030+4043 field, and in particular of Cygnus X-3.

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Vela X-1 in highly active hard X-ray state

ATel #1782; P. Soffitta, E. Costa, E. Del Monte, I. Donnarumma, Y. Evangelista, M. Feroci, I. Lapshov, F. Lazzarotto, L. Pacciani, M. Rapisarda, A. Argan, A. Trois , M. Tavani, G. Piano, G. Pucella, F. D'Ammando, V. Vittorini (INAF/IASF Roma), A. Bulgarelli, F. Gianotti, M. Trifoglio, G. Di Cocco, C. Labanti, F. Fuschino, M. Marisaldi, M. Galli, (INAF/IASF Bologna), A. Chen, S. Vercellone, A. Giuliani, S. Mereghetti, F. Perotti, P. Caraveo (INAF/IASF Milano), A. Pellizzoni (OAC/INAF Cagliari), G.Barbiellini, F. Longo, E. Vallazza (INFN Trieste), P. Picozza, A. Morselli (INFN Roma-2), M. Prest (Universita` dell'Insubria), P. Lipari, D. Zanello (INFN Roma-1), A. Rappoldi (INFN Pavia) and C. Pittori, F. Verrecchia, P.Santolamazza, B. Preger, P. Giommi (ASDC) and L. Salotti (ASI)
on 15 Oct 2008; 14:54 UT
Distributed as an Instant Email Notice (Request for Observations)
Password Certification: Marco Feroci (marco.feroci@iasf-roma.inaf.it)

Subjects: X-ray, Request for Observations, Binaries, Neutron Stars, Transients

The current pointing of the AGILE mission at (l,b)=(256,-20), started on 10th October 2008, includes the Vela region. In particular, Vela X-1 lies at approximately 25 degrees off-axis. Between MJD 54750 and 54752 (October 11-13) this source was detected by SuperAGILE with a flux varying in the range 250 mCrab - 1 Crab in 20-60 keV. Starting on MJD 54752.5 the flux showed a large and intense flare lasting approximately 12 hours and peaking at 2.3 Crab (AGILE orbit - 90 minutes - average), with a rise time of about 7 hours. After the flare, the source flux averaged again at about 500 mCrab for one day and at MJD 54753.8 (October 14) started a new flare that is currently ongoing. In its brightest periods, the 283.5-s spin pulsation of the source was directly visible on the raw light curve of the SuperAGILE experiment. During this period of large activity the source also exhibited intense activity on short time scale. A short flare occurred today, 15th October 2008, at 05:49 UT and lasted about 100 s, during which the source average flux was about 4 Crabs. The AGILE pointing to the Vela region is planned to end on 17th October 2008, 12 UT. The SuperAGILE orbital light curve of Vela X-1 may be found at the AGILE Science Data Center website: http://agile.asdc.asi.it/news.html.

 

 

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SuperAGILE detects an X-ray burst from SAX J1750.8-2900

ATel #1775; L. Pacciani, E. Costa, E. Del Monte, I. Donnarumma, Y. Evangelista, M. Feroci, I. Lapshov, F. Lazzarotto, M. Rapisarda, P. Soffitta, A. Argan, A. Trois , M. Tavani, G. Piano, G. Pucella, F. D'Ammando, V. Vittorini (INAF/IASF Roma), A. Bulgarelli, F. Gianotti, M. Trifoglio, G. Di Cocco, C. Labanti, F. Fuschino, M. Marisaldi, M. Galli, (INAF/IASF Bologna), A. Chen, S. Vercellone, A. Giuliani, S. Mereghetti, F. Perotti, F. Fornari, M. Fiorini, P. Caraveo (INAF/IASF Milano), A. Pellizzoni (OAC/INAF Cagliari), G.Barbiellini, F. Longo, E. Vallazza (INFN Trieste), P. Picozza, A. Morselli (INFN Roma-2), M. Prest (Universita` dell'Insubria), P. Lipari, D. Zanello (INFN Roma-1), A. Rappoldi (INFN Pavia) and C. Pittori, F. Verrecchia, P.Santolamazza, B. Preger, P. Giommi (ASDC) and L. Salotti (ASI)
on 10 Oct 2008; 13:33 UT
Distributed as an Instant Email Notice (Transients)
Password Certification: Marco Feroci (marco.feroci@iasf-roma.inaf.it)

Subjects: Binaries, Neutron Stars, Transients

While pointing at the Galactic Center region, SuperAGILE detected an X-ray burst from a position consistent with the neutron star transient SAX J1750.8-2900. This source was recently reported by Linares et al. (ATel #1662) as returning to a quiescent state, based on a Swift/XRT observation on August 14th 2008 (ATel #1662), after a long outburst started on March 2008 (Markwardt & Swank, ATel #1425), during which also SuperAGILE detected the source at hard X-rays at a flux level of about 80 mCrab (Pacciani et al., ATel #1428). The observed X-ray burst lasted approximately 60 sec, starting on 9 October 2008 at 21:26:04 UT. The average flux in the 17-25 keV energy range was about 2.3 Crab, while no significant signal is detected above 25 keV. A search in the SuperAGILE data in the 60 and 600 sec preceding and following the burst provided no evidence of prolonged source activity. The source is currently not detected by SuperAGILE in the standard 20-60 keV energy range, on a daily timescale, with a 3-sigma upper limit of about 20 mCrab.

 

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SuperAGILE detects an X-ray burst from the Millisecond Pulsar SAX J1808.4-3658

ATel #1732; E. Del Monte, Y. Evangelista, M. Feroci, I. Donnarumma, F. Lazzarotto, L. Pacciani, P. Soffitta, E. Costa, I. Lapshov, M. Rapisarda, M. Tavani, G. Pucella, F. D'Ammando, V. Vittorini, A. Argan, A. Trois (INAF/IASF Rome), A. Giuliani, S. Vercellone, A. Chen, S. Mereghetti, A. Pellizzoni, F. Perotti, F. Fornari, P. Caraveo (INAF/IASF Milan), A. Bulgarelli, F. Gianotti, M. Trifoglio, G. Di Cocco, C. Labanti, F. Fuschino, M. Marisaldi, M. Galli, (INAF/IASF Bologna), G. Barbiellini, F. Longo, E. Vallazza (INFN Trieste), P. Picozza, A. Morselli (INFN Roma-2), M. Prest, (Universita` dell'Insubria), P. Lipari, D. Zanello (INFN Roma-1), and C. Pittori, F. Verrecchia, B. Preger, P. Santolamazza, S. Colafrancesco, P. Giommi (ASDC) and L. Salotti (ASI)
on 23 Sep 2008; 20:04 UT
Distributed as an Instant Email Notice (Request for Observations)
Password Certification: Marco Feroci (marco.feroci@iasf-roma.inaf.it)

Subjects: X-ray, Request for Observations, Binaries, Transients
Referred to by ATel #: 1748

On 2008 September 23, 16:59:40 UT SuperAGILE detected and localized a bright X-ray burst, approximately 15 s long. The event is clearly detected only at energies below about 25 keV. The reconstructed position is RA=272.0930 and Dec=-36.9624, with an error radius of 3 arcmin. This position lies only 1.4 arcmin from the millisecond pulsar SAX J1808.4-3658. This source was recently reported by RXTE/PCA (Markwardt and Swank, ATel #1728) to have entered a new period of activity. SuperAGILE thus confirms the new outburst from SAX J1808.4-3658 and detects its renewed bursting activity.

 

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SuperAGILE detects IGR J16318-4848 in a bright state at hard X-rays

ATel #1713; L. Pacciani, M. Feroci, E. Del Monte, Y. Evangelista, I. Donnarumma, F. Lazzarotto, P. Soffitta, E. Costa, I. Lapshov, M. Rapisarda, M. Tavani, G. Pucella, F. D'Ammando, V. Vittorini, A. Argan, A. Trois (INAF/IASF Rome), A. Giuliani, S. Vercellone, A. Chen, S. Mereghetti, A. Pellizzoni, F. Perotti, F. Fornari, P. Caraveo (INAF/IASF Milan), A. Bulgarelli, F. Gianotti, M. Trifoglio, G. Di Cocco, C. Labanti, F. Fuschino, M. Marisaldi, M. Galli, (INAF/IASF Bologna), G. Barbiellini, F. Longo, E. Vallazza (INFN Trieste), P. Picozza, A. Morselli (INFN Roma-2), M. Prest, (Universita` dell'Insubria), P. Lipari, D. Zanello (INFN Roma-1), and C. Pittori, F. Verrecchia, B. Preger, P. Santolamazza, S. Colafrancesco, P. Giommi (ASDC) and L. Salotti (ASI)
on 10 Sep 2008; 20:20 UT
Distributed as an Instant Email Notice (Request for Observations)
Password Certification: Marco Feroci (marco.feroci@iasf-roma.inaf.it)

Subjects: X-ray, Request for Observations, Binaries, Transients

The AGILE mission started today (2008, Sept. 10, satellite maneuver started at 12:00pm) a 1-month pointing towards the Galactic Center region. The first data taken by SuperAGILE showed the Compton-thick X-ray binary IGR J16318-4848 (Walter et al. 2003, A&A 411, L427) in a bright state. The average 20-60 keV flux measured by SuperAGILE is about 300 mCrab, that turns out to be 10 times larger than its average 20-40 keV flux level of 25 mCrab, as reported in the 3rd INTEGRAL/ISGRI catalog (Bird et al. 2007, ApJS 170, 175). A preliminary analysis of the SuperAGILE data shows an increasing trend of the hard X-ray flux. AGILE will continue to monitor the Galactic Center region until 2008, October 10.

 

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SGR 0501+4516: AGILE observations

ATel #1705; M. Feroci, L. Pacciani, E. Del Monte, Y. Evangelista, I. Donnarumma, F. Lazzarotto, P. Soffitta, E. Costa, I. Lapshov, M. Rapisarda (INAF/IASF Rome), A. Giuliani, S. Vercellone, A. Chen, S. Mereghetti, A. Pellizzoni, F. Perotti, F. Fornari, P. Caraveo (INAF/IASF Milan), A. Bulgarelli, F. Gianotti, M. Trifoglio, G. Di Cocco, C. Labanti, F. Fuschino, M. Marisaldi, M. Galli, (INAF/IASF Bologna), M. Tavani, G. Pucella, F. D'Ammando, V. Vittorini, A. Argan, A. Trois (INAF/IASF Rome), G. Barbiellini, F. Longo (INFN Trieste), P. Picozza, A. Morselli (INFN Roma-2), M. Prest, E. Vallazza (Universita` dell'Insubria), P. Lipari, D. Zanello (INFN Roma-1), and C. Pittori, F. Verrecchia, B. Preger, P. Santolamazza, S. Colafrancesco, P. Giommi (ASDC) and L. Salotti (ASI)
on 8 Sep 2008; 15:07 UT
Password Certification: Marco Feroci (marco.feroci@iasf-roma.inaf.it)

Subjects: X-ray, Gamma Ray, Soft Gamma-ray Repeaters

The AGILE mission started a Target of Opportunity observation on the new soft gamma repeater SGR 0501+4516 (Barthelmy et al., GCN 8113) on 2008 August 31st, 12 UT. After the first week of observation, only 2 short bursts were detected with SuperAGILE from this source. Under the assumption of a Crab-like spectrum, the burst properties in the 17-60 keV energy range are:

          Date         Duration     10-ms Peak Flux   Fluence 
(UT) (ms) (erg/cm2/s) (erg/cm2)

2008-09-03 10:06:38 50 2.3e-6 6.4e-8
2008-09-03 18:53:51 70 1.9e-6 7.6e-8
Other events may have occurred in the periods when the source was occulted to the AGILE view by the Earth (approximately 35% of the time, on the average). Another event had been detected by SuperAGILE through the collimator shields on 2008-08-26 03:16:15 UT (100 ms, very bright, also detected by Konus-Wind, Konus-Wind team, private communication), when AGILE was pointing 140 degrees away from the SGR.
The two bursts of 2008-09-03 were not detected by the MCAL and GRID instruments. The MCAL 3-sigma upper limit is 4e-8 erg/cm2 in the 0.5-1 MeV energy range, over the burst duration as observed by SuperAGILE.
No persistent emission was observed at the position of SGR 0501+4516 by either SuperAGILE or GRID. The 3-sigma upper limit in the 20-60 keV energy range is about 8 mCrab, consistent with the 2 mCrab detection by INTEGRAL (Hurley & Gotz, GCN 8163). The 2-sigma upper limit in the >100 MeV energy range is 13e-8 ph/cm2/s.
The AGILE observation will continue until 2008 September 10th.
 

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AGILE detection of the high Galactic latitude transient gamma-ray source AGL J0229+2054

ATel #1641; A. Bulgarelli (INAF/IASF Bologna), M. Tavani, G. Pucella, F. D'Ammando, V. Vittorini, G. Piano, E. Costa, M. Feroci, I. Donnarumma, L. Pacciani, E. Del Monte, F. Lazzarotto, P. Soffitta, Y. Evangelista, I. Lapshov, M. Rapisarda, A. Argan, A. Trois, G. De Paris, A. Rubini, (INAF/IASF Roma), F. Gianotti, M. Trifoglio,G. Di Cocco, C. Labanti, F. Fuschino, M. Marisaldi, E. Morelli, M. Galli (INAF/IASF Bologna), A. Chen, P. Caraveo, A. Giuliani, S. Mereghetti, A. Pellizzoni, S. Vercellone, F. Perotti, F. Fornari, M. Fiorini, A. Zambra (INAF/IASF Milano), G. Barbiellini, F. Longo, E. Vallazza (INFN Trieste), P. Picozza, A. Morselli (INFN Roma-2), M. Prest (Universita` dell'Insubria), P. Lipari, D. Zanello (INFN Roma-1), P. Cattaneo (INFN Pavia), C. Pittori, F. Verrecchia, D. Gasparrini, P. Santolamazza, S. Colafrancesco, P. Giommi (ASDC) and L. Salotti (ASI)
on 1 Aug 2008; 15:24 UT
Password Certification: Marco Tavani (tavani@iasf-roma.inaf.it)

Subjects: X-ray, Gamma Ray, AGN, Transients
Referred to by ATel #: 1645

During the current AGILE pointing centered at Galactic coordinates l = 134.7, b = -23.1, the Gamma-Ray Imaging Detector (GRID) discovered a fast variable gamma-ray source at high Galactic latitude. Integrating from 2008-07-30 15:34 UT to 2008-07-31 15:23, a maximum likelihood analysis shows a detection at a significance level above 5 sigma, with a source flux in excess of about 100e-8 ph/cm2/s for photon energies larger than 100 MeV. The source positional error box is centered at Galactic coordinates l = 151.7 deg, b = -36.4 deg (R.A. = 02h 29m 33s, DEC = +20d 54m 47s) and has a preliminary 95% confidence radius of about 1 degree. We name this source AGL J0229+2054. A preliminary analysis of the Super-AGILE data during the same time period and in the same sky region does not show any hard X-ray counterpart in the 20-60 keV energy range, with a 3-sigma upper limit of 30 mCrab on the average flux. We note that the source is now under the AGILE-GRID detection threshold, implying a strong variability above 100 MeV on short time-scales. We notice the presence at approximately 22' from the GRID error box centroid of a 100 mJy radio source at 5 GHz (CRATES J023030+211241). In addition, we notice the presence near the AGILE-GRID error box of the prominent blazar 1ES 0229+200, at a position approximately 61.3' from the GRID error box centroid. The AGILE monitoring of the field including this source will continue until 2008-08-15 12:00 UT. We strongly encourage multi-frequency observations of the AGL J0229+2054 field, and in particular of the blazar 1ES 0229+200 and of the source CRATES J023030+211241.

 

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AGILE detection of continued gamma-ray activity of the blazar 3C 454.3

ATel #1634; C. Pittori, F. Verrecchia (ASDC), S. Vercellone (INAF/IASF Milan), F. D'Ammando (INAF/IASF Rome), M. Marisaldi (INAF/IASF Bologna), A. Chen, A. Giuliani, S. Mereghetti, A. Pellizzoni, F. Perotti, F. Fornari, M. Fiorini, P. Caraveo, A. Zambra (INAF/IASF Milan), A. Bulgarelli, G. Di Cocco, F. Fuschino, M. Galli, F. Gianotti, C. Labanti, M. Trifoglio (INAF/IASF Bologna), A. Argan, E. Costa, E. Del Monte, G. De Paris, I. Donnarumma, Y. Evangelista, M. Feroci, I. Lapshov, F. Lazzarotto, L. Pacciani, G. Piano, G. Pucella, M. Rapisarda, P. Soffitta, M. Tavani, A. Trois, V. Vittorini (INAF/IASF Rome), G. Barbiellini, F. Longo, E. Vallazza (INFN Trieste), P. Picozza, A. Morselli (INFN Roma-2), M. Prest, (Universita` dell'Insubria), P. Lipari, D. Zanello (INFN Roma-1), F. Boffelli, P. Cattaneo (INFN Pavia), P.Santolamazza, B. Preger, S. Colafrancesco, P. Giommi (ASDC) and L. Salotti (ASI)
on 28 Jul 2008; 14:27 UT
Password Certification: Carlotta Pittori (carlotta.pittori@asdc.asi.it)

Subjects: Gamma Ray, >GeV, AGN, Quasars
Referred to by ATel: #1849

AGILE detection of continued gamma-ray activity of the blazar 3C 454.3 During a dedicated Target of Opportunity repointing, triggered by the GLAST-LAT detection of 3C 454.3 above 100 MeV (ATEL #1628), the AGILE Gamma Ray Imaging Detector (GRID) detected 3C 454.3 in high state in the period between 2008-07-25 18:00 UT and 2008-07-28 03:00 UT. A preliminary maximum likelihood analysis shows a detection at a significance level above 5 sigma, with a source flux in excess of about 200e-8 ph/cm2/s for E>100 MeV. The AGILE monitoring of the source will continue till 2008-07-31 12:00 UT. We strongly encourage multi-frequency observations of 3C 454.3 during this gamma-ray high-state monitored by AGILE and GLAST.

 

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GRO J1008-57 entering a new outburst at hard X-rays

ATel #1619; Y. Evangelista, I. Donnarumma, E. Del Monte, M. Feroci, E. Costa, I. Lapshov, F. Lazzarotto, L. Pacciani, M. Rapisarda, P. Soffitta, A. Argan, A. Trois , M. Tavani, G. Pucella, F. D'Ammando, V. Vittorini (INAF/IASF Roma), A. Chen, S. Vercellone, A. Giuliani, S. Mereghetti, A. Pellizzoni, F. Perotti, F. Fornari, M. Fiorini, P. Caraveo (INAF/IASF Milano), A. Bulgarelli, F. Gianotti, M. Trifoglio, G. Di Cocco, C. Labanti, F. Fuschino, M. Marisaldi, M. Galli, (INAF/IASF Bologna), G. Barbiellini, F. Longo, E. Vallazza (INFN Trieste), P. Picozza, A. Morselli (INFN Roma-2), M. Prest (Universita` dell'Insubria), P. Lipari, D. Zanello (INFN Roma-1), P. Cattaneo (INFN Pavia), C. Pittori, B. Preger, P. Santolamazza, F. Verrecchia, P. Giommi (ASDC) and L. Salotti (ASI)
on 18 Jul 2008; 11:31 UT
Distributed as an Instant Email Notice (Request for Observations)
Password Certification: Marco Feroci (marco.feroci@iasf-roma.inaf.it)

Subjects: X-ray, Request for Observations, Binaries, Neutron Stars, Transients

During the current AGILE pointing at the Vela region, started on 2008 June 30, SuperAGILE detects increasing hard X-ray emission from the Be transient binary pulsar GRO J1008-57, usually below the detection threshold on day-timescale. In the 20-60 keV energy range the source was detected at 30 mCrab level in the 24 hours starting on 2008 July 15 09:00 UT. In the subsequent 24 hours the average flux increased to 45 mCrab, and in the last 24 hours it rose to about 65 mCrab. The last reported outburst from this source dates to November 2007 (Krimm et al., ATel #1298, Wilms et al. ATel #1304), thus the time of the ongoing outburst confirms the good agreement between the recurrence time of outbursts and the proposed binary period of about 248 days (e.g., Coe et al., 2007, MNRAS 378, 1427).

 

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AGILE detection of new flaring activity from blazar 3C 454.3

ATel #1592; D. Gasparrini, C. Pittori, F. Verrecchia, B. Preger, P. Santolamazza, S. Colafrancesco, P. Giommi (ASDC), S. Vercellone, A. Chen, A. Giuliani (INAF/IASF Milan), I. Donnarumma, F. D'Ammando, L. Pacciani, G. Pucella, V. Vittorini (INAF/IASF Rome), F. Longo (INFN, Trieste), A. Bulgarelli (INAF/IASF Bologna), S. Mereghetti, A. Pellizzoni, F. Perotti, F. Fornari, M. Fiorini, P. Caraveo, A. Zambra (INAF/IASF Milan), F. Gianotti, M. Trifoglio, G. Di Cocco, C. Labanti, F. Fuschino, M. Marisaldi, M. Galli, (INAF/IASF Bologna), M. Tavani, E. Costa, M. Feroci, E. Del Monte, F. Lazzarotto, G. Piano, P. Soffitta, Y. Evangelista, I. Lapshov, M. Rapisarda, A. Argan, A. Trois, G. De Paris (INAF/IASF Rome), G. Barbiellini, E. Vallazza (INFN Trieste), P. Picozza, A. Morselli (INFN Roma-2), M. Prest, (Universita` dell'Insubria), P. Lipari, D. Zanello (INFN Roma-1), F. Boffelli, P. Cattaneo (INFN Pavia) and L. Salotti (ASI)
on 26 Jun 2008; 17:06 UT
Password Certification: Carlotta Pittori (carlotta.pittori@asdc.asi.it)

Subjects: Gamma Ray, >GeV, AGN, Quasars

During the current Observing Block started on 2008-06-15 12:00 UT, the AGILE Gamma Ray Imaging Detector (GRID) detected 3C 454.3 in high state in the period between 2008-06-25 03:00 UT and 2008-06-26 03:00 UT.

A preliminary maximum likelihood analysis shows a detection at a significance level above 5 sigma, with a source flux in excess of about 200e-8 ph/cm2/s for E>100 MeV.

3C 454.3 was previously detected in high state several times by the AGILE-GRID during 2007 and 2008 (see also ATels #1160, #1167, #1278, #1300 and #1545). A very recent gamma-ray flare episode is reported in ATel #1581.

The AGILE monitoring of the source will continue till 2008-06-30 12:00 UT. We strongly encourage multi-frequency observations of 3C 454.3 during this gamma-ray high-state.

 

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AGILE detection of the flaring gamma-ray source AGL2021+4029: a possible rebrightening of a strong source in the Cygnus region

ATel #1585; A. Chen, P. Caraveo, A. Giuliani, S. Mereghetti, A. Pellizzoni, S. Vercellone, F. Perotti, F. Fornari, M. Fiorini, A. Zambra (INAF/IASF Milano), M. Tavani, G. Pucella, F. D'Ammando, V. Vittorini, E. Costa, M. Feroci, I. Donnarumma, L. Pacciani, E. Del Monte, F. Lazzarotto, P. Soffitta, Y. Evangelista, I. Lapshov, M. Rapisarda, A. Argan, A. Trois, G. De Paris (INAF/IASF Roma), A. Bulgarelli, F. Gianotti, M. Trifoglio, G. Di Cocco, C. Labanti, F. Fuschino, M. Marisaldi, M. Galli (INAF/IASF Bologna), G. Barbiellini, F. Longo, E. Vallazza (INFN Trieste), P. Picozza, A. Morselli (INFN Roma-2), M. Prest (Universita` dell'Insubria), P. Lipari, D. Zanello (INFN Roma-1), P. Cattaneo (INFN Pavia) and C. Pittori, F. Verrecchia, B. Preger, P. Santolamazza, P. Giommi
on 23 Jun 2008; 17:31 UT
Password Certification: Andrew Chen (chen@iasf-milano.inaf.it)

Subjects: Gamma Ray, >GeV, Transients, Variables

Integrating from 2007-11-02 12:00 UT to 2008-05-01 00:00, AGILE-GRID (Gamma-Ray Imaging Detector) detects a gamma-ray point source above 19 sigma, with a source flux in excess of 100e-8 ph/cm2/s at energies above 100 MeV. The source positional error box is centered at Galactic coordinates l = 78.31 deg, b = 2.05 deg, and has a radius of about 0.25 degrees. The nearest EGRET source is 3EG J2020+4017 at (l,b) = (78.05,2.08) with an error radius of 0.16 degrees.

The position of this source is consistent with the transient sources previously reported in ATel #1492 and #1547. We note that although the flux reported in #1492 is significantly higher than the mean integrated flux, the flux during the #1547 is consistent with the mean value. We also note that the position of the proposed counterpart IGR J20187+4041 = 2MASX J20183871+4041003 (ATel #1497, #1498, #1518, #1584) lies OUTSIDE the 95% source location contour of the integrated source.

While pointing at the Cygnus region, AGILE detected renewed gamma-ray emission consistent with this source, beginning on 2008-06-20 UT. A preliminary maximum likelihood analysis of the gamma-ray data obtained between 2008-06-20 16:30 UT and 2008-06-21 16:30 UT for photon energies above 100 MeV results in a detection significance of about 4.9 sigma, with a source flux in excess of 200e-8 ph/cm2/s at energies above 100 MeV, two standard deviations higher than the mean flux of the integrated source. The source positional error box is centered at Galactic coordinates l = 78.6 deg, b = 1.7 deg, and has a radius of about 0.6 degrees. We note that the position is consistent with the integrated source, while 2MASX J20183871+4041003 lies outside the 95% source location contour.

A preliminary analysis of the Super-AGILE data over the same time period and the same sky region does not show any counterpart in the 20-60 keV energy range, with a 3-sigma upper limit of 20 mCrab on the average flux.

We strongly encourage multi-frequency observations of the field of the gamma-ray source detected by AGILE in an active gamma-ray flaring state, concentrating on the error box of the persistent source.

 

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AGILE detection of the blazar Mrk 421

ATel #1583; C. Pittori, Sara Cutini, Dario Gasparrini, F. Verrecchia, S. Colafrancesco, P. Giommi (ASDC),S. Vercellone, A. Chen, A. Giuliani (INAF/IASF Milan), I. Donnarumma, F. D'Ammando, L. Pacciani, G. Pucella, V. Vittorini (INAF/IASF Rome), F. Longo (INFN, Trieste), A. Bulgarelli (INAF/IASF Bologna), S. Mereghetti, A. Pellizzoni, F. Perotti, F. Fornari, M. Fiorini, P. Caraveo, A. Zambra (INAF/IASF Milan), F. Gianotti, M. Trifoglio, G. Di Cocco, C. Labanti, F. Fuschino, M. Marisaldi, M. Galli, (INAF/IASF Bologna), M. Tavani, E. Costa, M. Feroci, E. Del Monte, F. Lazzarotto, G. Piano, P. Soffitta, Y. Evangelista, I. Lapshov, M. Rapisarda, A. Argan, A. Trois, G. De Paris (INAF/IASF Rome), G. Barbiellini, E. Vallazza (INFN Trieste), P. Picozza, A. Morselli (INFN Roma-2), M. Prest, (Universita` dell'Insubria), P. Lipari, D. Zanello (INFN Roma-1), P. Cattaneo (INFN Pavia), L. Salotti (ASI), and J. Grube (University of Leeds)
on 17 Jun 2008; 12:47 UT
Password Certification: Carlotta Pittori (carlotta.pittori@asdc.asi.it)

Subjects: Gamma Ray, AGN, Quasars

The AGILE Gamma Ray Imaging Detector (GRID) detected Mrk 421 in the period between 2008-06-09 17:02 UT and 2008-06-15 02:17 UT during a Target of Opportunity (ToO) re-pointing towards W Comae. A preliminary maximum likelihood analysis shows a detection at a significance level of about 4 sigma, at energies above 100 MeV. During the AGILE ToO, the Super-AGILE hard X-ray monitor detected Mrk 421 in a relatively high-state, with a source flux of about 40 mCrab, in the energy range 18-60 keV (see Costa et al., ATEL #1574). The source is an approved target of the AGILE Announcement of Opportunity, Cycle 1 (PI: J. Grube).

 

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AGILE detection of the blazar W Comae in the gamma-ray energy band

ATel #1582; F. Verrecchia, Dario Gasparrini, Sara Cutini, B. Preger, C. Pittori, S. Colafrancesco, P. Giommi (ASDC), S. Vercellone, A. Chen, A. Giuliani (INAF/IASF Milan), I. Donnarumma, F. D'Ammando, L. Pacciani, G. Pucella, V. Vittorini (INAF/IASF Rome), F. Longo (INFN, Trieste), A. Bulgarelli (INAF/IASF Bologna), S. Mereghetti, A. Pellizzoni, F. Perotti, F. Fornari, M. Fiorini, P. Caraveo, A. Zambra (INAF/IASF Milan), F. Gianotti, M. Trifoglio, G. Di Cocco, C. Labanti, F. Fuschino, M. Marisaldi, M. Galli, (INAF/IASF Bologna), M. Tavani, E. Costa, M. Feroci, E. Del Monte, F. Lazzarotto, G. Piano, P. Soffitta, Y. Evangelista, I. Lapshov, M. Rapisarda, A. Argan, A. Trois, G. De Paris (INAF/IASF Rome), G. Barbiellini, E. Vallazza (INFN Trieste), P. Picozza, A. Morselli (INFN Roma-2), M. Prest, (Universita` dell'Insubria), P. Lipari, D. Zanello (INFN Roma-1), P. Cattaneo (INFN Pavia), L. Salotti (ASI), and E. Pian (INAF/OAT)
on 17 Jun 2008; 12:42 UT
Password Certification: Carlotta Pittori (carlotta.pittori@asdc.asi.it)

Subjects: Gamma Ray, >GeV, AGN, Quasars

The AGILE Gamma Ray Imaging Detector (GRID) detected W Comae in the period between 2008-06-09 17:02 UT and 2008-06-15 02:17 UT during a Target of Opportunity re-pointing in response to the source detection in the TeV energy band (see Swordy et al., ATEL #1565). A preliminary maximum likelihood analysis shows a detection at a significance level of about 4 sigma, at energies above 100 MeV. The source is an approved target of the AGILE Announcement of Opportunity, Cycle 1 (PI: E. Pian).

 

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Blazar 3C 454.3 in gamma-ray high state: new AGILE detection

ATel #1581; V. Vittorini, I. Donnarumma, F. D'Ammando, L. Pacciani, G. Pucella, (INAF/IASF Rome), A. Chen, A. Giuliani, S. Vercellone (INAF/IASF Milan), F. Longo (INFN, Trieste), A. Bulgarelli (INAF/IASF Bologna), S. Mereghetti, A. Pellizzoni, F. Perotti, F. Fornari, M. Fiorini, P. Caraveo, A. Zambra (INAF/IASF Milan), F. Gianotti, M. Trifoglio, G. Di Cocco, C. Labanti, F. Fuschino, M. Marisaldi, M. Galli, (INAF/IASF Bologna), M. Tavani, E. Costa, M. Feroci, E. Del Monte, F. Lazzarotto, G. Piano, P. Soffitta, Y. Evangelista, I. Lapshov, M. Rapisarda, A. Argan, A. Trois , G. De Paris (INAF/IASF Rome), G. Barbiellini, E. Vallazza (INFN Trieste), P. Picozza, A. Morselli (INFN Roma-2), M. Prest, (Universita` dell'Insubria), P. Lipari, D. Zanello (INFN Roma-1), P. Cattaneo (INFN Pavia) and C. Pittori, F. Verrecchia, B. Preger, P. Santolamazza, P. Giommi (ASDC) and L. Salotti (ASI)
on 16 Jun 2008; 16:21 UT
Password Certification: Stefano Vercellone (stefano@iasf-milano.inaf.it)

Subjects: Gamma Ray, AGN, Quasars

The AGILE Gamma Ray Imaging Detector (GRID) detected 3C 454.3 in high state in the period between 2008-06-15 10:46 UT and 2008-06-16 07:11 UT.

Despite the fact that the source is currently more than 35 degrees off-axis, a preliminary maximum likelihood analysis shows a detection at a significance level of about 5 sigma, with a source flux in excess of 100e-8 ph/cm2/s at energies above 100 MeV. This source was already detected in the gamma-ray energy band by the AGILE-GRID in July, November, and December 2007 (see ATELs #1160, #1167, #1278, and #1300) and also during the period May 24 - June 9 2008 (see ATEL #1545).

Monitoring of the source by AGILE will continue till 2008-06-30 12:00 UT. We strongly encourage multi-frequency observations of 3C 454.3 during this gamma-ray high-state.

 

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SuperAGILE detects enhanced hard X-ray emission from Mkn 421

ATel #1574; E. Costa, E. Del Monte, I. Donnarumma, Y. Evangelista, M. Feroci, I. Lapshov, F. Lazzarotto, L. Pacciani, M. Rapisarda, P. Soffitta, A. Argan, A. Trois , M. Tavani, G. Pucella, F. D'Ammando, V. Vittorini (INAF/IASF Roma), A. Chen, S. Vercellone, A. Giuliani, S. Mereghetti, A. Pellizzoni, F. Perotti, F. Fornari, M. Fiorini, P. Caraveo (INAF/IASF Milano), A. Bulgarelli, F. Gianotti, M. Trifoglio, G. Di Cocco, C. Labanti, F. Fuschino, M. Marisaldi, M. Galli, (INAF/IASF Bologna), G. Barbiellini, F. Longo, E. Vallazza (INFN Trieste), P. Picozza, A. Morselli (INFN Roma-2), M. Prest (Universita` dell'Insubria), P. Lipari, D. Zanello (INFN Roma-1), P. Cattaneo (INFN Pavia), C Pittori,F. Verrecchia, B. Preger, P. Giommi (ASDC) and L. Salotti (ASI)
on 12 Jun 2008; 15:42 UT
Distributed as an Instant Email Notice (Request for Observations)
Password Certification: Marco Feroci (marco.feroci@iasf-roma.inaf.it)

Subjects: X-ray, Gamma Ray, Request for Observations, AGN

During an AGILE pointing at the North Galactic Pole region aiming at WComae, started on 2008 June 9 18:00 UT, SuperAGILE detected enhanced hard X-ray emission from the BL Lac source Mkn 421, lying approximately 17 degrees off-axis with respect to the center of the field of view. The measured average 20-60 keV flux was 32 mCrab between 2008 June 10 06:30 UT and 2008 June 11 06:30 UT, and 41 mCrab between 2008 June 11 06:30 UT and 2008 June 12 08:00 UT. The latest reported hard X-ray activity of Mkn 421 was on 2008 March when Swift/BAT (Krimm et al., ATel #1449) detected flaring activity from 22 to 110 mCrab in the 15-50 keV energy range. AGILE will continue on monitoring the same sky region for the next 3 days, with both the hard X-ray monitor SuperAGILE and the gamma-ray imager GRID.

 

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Rebrightening of the variable AGILE source in the Cygnus region

ATel #1547; A. Giuliani, P. Caraveo, A. Chen, S. Mereghetti, A. Pellizzoni, S. Vercellone, F. Perotti, F. Fornari, M. Fiorini, A. Zambra (INAF/IASF Milano), M. Tavani, G. Pucella, F. D'Ammando, V. Vittorini, E. Costa, M. Feroci, I. Donnarumma, L. Pacciani, E. Del Monte, F. Lazzarotto, P. Soffitta, Y. Evangelista, I. Lapshov, M. Rapisarda, A. Argan, A. Trois, G. De Paris (INAF/IASF Roma), A. Bulgarelli, F. Gianotti, M. Trifoglio, G. Di Cocco, C. Labanti, F. Fuschino, M. Marisaldi, M. Galli, (INAF/IASF Bologna), G. Barbiellini, F. Longo, (INFN Trieste), P. Picozza, A. Morselli (INFN Roma-2), M. Prest, E. Vallazza (Universita` dell'Insubria), P. Lipari, D. Zanello (INFN Roma-1), P. Cattaneo (INFN Pavia) and P. Giommi, C. Pittori, D. Gasparrini, S. Cutini, B. Preger, P. Santolamazza, F. Verrecchia (ASDC) and L. Salotti (ASI)
on 27 May 2008; 17:29 UT
Password Certification: Andrew Chen (chen@iasf-milano.inaf.it)

Subjects: Gamma Ray, >GeV, Transients

While pointing at the Cygnus region, AGILE detected renewed gamma-ray emission from the transient gamma-ray source previously reported in ATel #1492, beginning on 2008-05-22 UT.

A preliminary maximum likelihood analysis of the AGILE-GRID (Gamma-Ray Imaging Detector) data obtained between 2008-05-22 06:00 UT and 2008-05-27 06:00 UT for photon energies above 100 MeV results in a detection significance of about 6 sigma, with a source flux in excess of 100e-8 ph/cm2/s at energies above 100 MeV. The source positional error box is centered at Galactic coordinates l = 77.9 deg, b = 2.6 deg, and has a radius of about 0.5 degrees. We note that the possible counterpart IGR J20187+4041 = 2MASX J20183871+4041003 (ATel #1497, #1498, #1518) lies within the 95% source location contour.

A preliminary analysis of the Super-AGILE data over the same time period and the same sky region does not show any counterpart in the 20-60 keV energy range, with a 3-sigma upper limit of 10 mCrab on the average flux.

We strongly encourage multi-frequency observations of the field of the gamma-ray source detected by AGILE in an active gamma-ray flaring state, including the possible counterpart IGR J20187+4041 = 2MASX J20183871+4041003.

 

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Renewed gamma ray activity of 3C 454.3 detected by AGILE

ATel #1545; I. Donnarumma, F. D'Ammando, L. Pacciani, G. Pucella, V. Vittorini (INAF/IASF Rome), A. Chen, A. Giuliani, S. Vercellone (INAF/IASF Milan), F. Longo (INFN, Trieste), A. Bulgarelli (INAF/IASF Bologna), S. Mereghetti, A. Pellizzoni, F. Perotti, F. Fornari, M. Fiorini, P. Caraveo, A. Zambra (INAF/IASF Milan), F. Gianotti, M. Trifoglio, G. Di Cocco, C. Labanti, F. Fuschino, M. Marisaldi, M. Galli, (INAF/IASF Bologna), M. Tavani, E. Costa, M. Feroci, E. Del Monte, F. Lazzarotto, P. Soffitta, Y. Evangelista, I. Lapshov, M. Rapisarda, A. Argan, A. Trois , G. De Paris (INAF/IASF Rome), G. Barbiellini, E. Vallazza (INFN Trieste), P. Picozza, A. Morselli (INFN Roma-2), M. Prest, (Universita` dell'Insubria), P. Lipari, D. Zanello (INFN Roma-1), P. Cattaneo (INFN Pavia) and P. Giommi, C. Pittori, D. Gasparrini, S. Cutini, B. Preger, P. Santolamazza, F. Verrecchia (ASDC) and L. Salotti (ASI)
on 27 May 2008; 13:10 UT
Distributed as an Instant Email Notice (Request for Observations)
Password Certification: Marco Feroci (marco.feroci@iasf-roma.inaf.it)

Subjects: Gamma Ray, AGN

The AGILE Gamma Ray Imaging Detector (GRID) detected new flaring activity from the blazar 3C 454.3 in the period between 2008-05-24 03:10 UT and 2008-05-27 04:17 UT. Despite the fact that the source is currently more than 35 degrees off-axis, a preliminary maximum likelihood analysis shows a detection at a significance level of about 9 sigma, with a source flux in excess of 100e-8 ph/cm2/s at energies above 100 MeV. This source was already detected in the gamma-ray energy band by the AGILE-GRID in July, November, and December 2007 (see ATELs #1160, #1167, #1278 and #1300). Monitoring of the source by AGILE will continue over the next weeks. We strongly encourage multi-frequency observations of 3C 454.3 during this new gamma-ray flaring state.

 

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Swift detection of the brightest X-ray flare from S50716+714

ATel #1495; P. Giommi(ASI/ASDC, Italy), M. Perri(ASDC/INAF, Italy), F. Verrecchia(ASDC/INAF, Italy ), C. Pittori(ASDC/INAF, Italy) , M. Tavani(INAF, Italy), N. Gehrels(NASA/GSFC, USA), M. Chester(PSU, USA)
on 29 Apr 2008; 13:52 UT
Password Certification: Claudia M. Raiteri (raiteri@oato.inaf.it)

Subjects: X-ray, AGN
Referred to by ATel #: 1500, 1502

On 28 April 2008 Swift detected the blazar S50716+714 at X-ray and UV flux levels significantly larger than ever observed before. An analysis of the XRT data gives a 0.3-10 keV X-ray flux of 4e-11 erg/cm2/s, about 50% larger than that observed at the peak of the giant X-ray flare of October-November 2007. Swift will continue the monitoring of S50716+714 over the next few days, while the AGILE Gamma-ray observatory will include this source within its field of view between April 30 and May 10, 2008. Multi-frequency observations are strongly encouraged.

 

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AGILE gamma-ray detection of a variable source in the Cygnus region

ATel #1492; F. Longo (INFN Trieste), A. Chen, S. Vercellone, P. Caraveo, A. Giuliani, S. Mereghetti, A. Pellizzoni, F. Perotti, F. Fornari, M. Fiorini (INAF/IASF Milano), A. Bulgarelli, F. Gianotti, M. Trifoglio, G. Di Cocco, C. Labanti, F. Fuschino, M. Marisaldi, M. Galli (INAF/IASF Bologna), M. Tavani, G. Pucella, F. D'Ammando, V. Vittorini, E. Costa, M. Feroci, I. Donnarumma, L. Pacciani, E. Del Monte, F. Lazzarotto, P. Soffitta, Y. Evangelista, I. Lapshov, M. Rapisarda, A. Argan, A. Trois, (INAF/IASF Roma), G. Barbiellini, E. Vallazza (INFN Trieste), P. Picozza, A. Morselli (INFN Roma-2), M. Prest (Universita` dell'Insubria), P. Lipari, D. Zanello (INFN Roma-1), P. Cattaneo (INFN Pavia), P. Giommi, C. Pittori, F. Verrecchia, P. Santolamazza, B. Preger (ASDC) and L. Salotti (ASI)
on 28 Apr 2008; 17:28 UT
Password Certification: Andrew Chen (chen@iasf-milano.inaf.it)

Subjects: X-ray, Gamma Ray, Transients

The AGILE satellite, currently in a Cycle-1 pointing centered approximately in the Vulpecula region, during the observing period that started on 2008-04-10 12:00 UT, detected significant and variable gamma-ray emission from the Galactic plane from a source positionally consistent with 3EG J2020+4017. The AGILE Quicklook Analysis provides the source positional error box that is centered at Galactic coordinates l = 78.01 deg, b = 2.19 deg, and has a radius of about 1 degree. A preliminary maximum likelihood analysis of the AGILE-GRID (Gamma-Ray Imaging Detector) data obtained between 2008-04-27 01:39 UT and 2008-04-28 01:27 UT for photon energies above 100 MeV results in a detection significance of about 5 sigma. A preliminary analysis of the Super-AGILE data over the same time period and the same sky region does not show any counterpart in the 20-60 keV energy range. The 3-sigma upper limit on the one-day average flux is 45 mCrab within the central region of the AGILE-GRID error box. Searches for counterparts in Chandra and ROSAT coverage of the 3EG~J2020+4017 error box (Weisskopf et al. 2006, ApJ, 652, 387; Becker et al., 2004, ApJ, 615, 897) yielded no compelling counterparts. We remark thatone of the many possible counterparts within the AGILE-GRID error box is the galaxy 2MASX J20183871+4041003 which has been claimed to have blazar-like characteristics (Iyudin et al., 2007, A&A, 468, 919). We strongly encourage multi-frequency observations of the entire field of the gamma-ray source detected by AGILE in an active gamma-ray flaring state.

 

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SuperAGILE detects an X-ray burst from a position consistent with IGR J17473-2721

ATel #1445; E. Del Monte, Y. Evangelista, M. Feroci, E. Costa, I. Donnarumma, I. Lapshov, F. Lazzarotto, L. Pacciani,M. Rapisarda, P. Soffitta, A. Argan, A. Trois , M. Tavani, G. Pucella, F. D'Ammando, V. Vittorini (INAF/IASF Roma), A. Chen, S. Vercellone, A. Giuliani, S. Mereghetti, A. Pellizzoni, F. Perotti, F. Fornari, M. Fiorini, P. Caraveo (INAF/IASF Milano), A. Bulgarelli, F. Gianotti, M. Trifoglio, G. Di Cocco, C. Labanti, F. Fuschino, M. Marisaldi, M. Galli, (INAF/IASF Bologna), G. Barbiellini, F. Longo, E. Vallazza (INFN Trieste), P. Picozza, A. Morselli (INFN Roma-2), M. Prest (Universita` dell'Insubria), P. Lipari, D. Zanello (INFN Roma-1), P. Cattaneo (INFN Pavia) and C Pittori, F. Verrecchia, B. Preger, P. Giommi (ASDC) and L. Salotti (ASI)
on 27 Mar 2008; 13:41 UT
Distributed as an Instant Email Notice(Transients)
Password Certification: Marco Feroci (marco.feroci@iasf-roma.inaf.it)

Subjects: X-ray, Binaries, Neutron Stars, Transients

During the AGILE pointing at the Galactic Center region SuperAGILE detected a burst from the sky position RA=266.842, Dec=-27.339 (error radius 3 arcmin). This position lies approximately 1.1 arcmin from the position of the source IGR J17473-2721 (Grebenev et al., ATel #467) and approximately 1 arcmin from the proposed counterpart detected by Swift/XRT (Kennea et al., ATel #500) and Chandra (Juett et al., ATel #521). The burst was detected on 26 March 2008, 23:19:40 UT, lasted approximately 40 s and it was significantly detected only in the energy range 17-25 keV. The average flux of the event was about 2.5 Crab. If the identification with IGR J17473-2721 is correct, assuming a distance of 8.5 kpc, the observed average flux corresponds to approximately 0.9 x 10^38 erg/s (17-25 keV), consistent with an Eddington limited flux for a neutron star mass. Considering the intensity, the temporal and spectral properties of the event as well as the spatial coincidence with the source IGR J17473-2721 near the Galactic Center, we propose that the burst observed by SuperAGILE was indeed a Type I X-ray burst, and suggest that IGR J17473-2721 is an X-ray burster.

 

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AGILE detection of a gamma-ray source coincident with Blazar PKS 1510-08

ATel #1436; F. D'Ammando (INAF/IASF Roma), A. Bulgarelli (INAF/IASF Bologna), S. Vercellone, A. Giuliani, A. Chen, S. Mereghetti, A. Pellizzoni, F. Perotti, F. Fornari, M. Fiorini, P. Caraveo, A. Zambra (INAF/IASF Milano), F. Gianotti, M. Trifoglio, G. Di Cocco, C. Labanti, F. Fuschino, M. Marisaldi, M. Galli, (INAF/IASF Bologna), M. Tavani, G. Pucella, V. Vittorini, E. Costa, M. Feroci, I. Donnarumma, L. Pacciani, E. Del Monte, F. Lazzarotto, P. Soffitta, Y. Evangelista, I. Lapshov, M. Rapisarda, A. Argan, A. Trois , G. De Paris (INAF/IASF Roma), G. Barbiellini, F. Longo, E. Vallazza (INFN Trieste), P. Picozza, A. Morselli (INFN Roma-2), M. Prest, (Universita` dell'Insubria), P. Lipari, D. Zanello (INFN Roma-1), F. Mauri (INFN Pavia) and P. Giommi, C. Pittori, D. Gasparrini, S. Cutini, B. Preger, P. Santolamazza, F. Verrecchia (ASDC) and L. Salotti (ASI)
on 20 Mar 2008; 15:08 UT
Password Certification: Stefano Vercellone (stefano@iasf-milano.inaf.it)

Subjects: Gamma Ray, AGN, Quasars

The AGILE satellite, currently in a Cycle-1 pointing centered on the Galactic Center region, during the observing period that started on 2008-03-16 12:00 UT, detected significant gamma-ray emission from a source at approximately 40 degrees off the AGILE pointing direction. The AGILE Quicklook Analysis provides the source positional error box that is centered at Galactic coordinates l = 351.61 deg, b = 40.09 deg, and has a radius of about 0.5 degrees. We note that this position is consistent with the radio position of the blazar PKS 1510-08 that has been associated with the gamma-ray source 3EG J1512-0849. This source was already detected by the AGILE-GRID (Gamma-Ray Imaging Detector) between 2007-08-27 14:48 UT and 2007-08-30 10:50 UT (see ATEL #1199 and ATEL #1204). A preliminary maximum likelihood analysis of the AGILE-GRID data obtained between 2008-03-18 03:00 UT and 2008-03-20 03:00 UT for photon energies above 100 MeV results in a detection significance of about 7 sigma.During the same period, the source was outside the Super-AGILE field of view. We strongly encourage multi-frequency observations of PKS 1510-08 detected by AGILE in an active gamma-ray flaring state.

SA_IGR_J17473-2721 SA IGR_J17473-2721

One-dimensional images of the X-ray burst as detected by SuperAGILE in its two sets of one-dimensional detectors, in the 17-25 keV energy range.

3D synthesis of the two one-dimensional images of the X-ray burst as
detected by SuperAGILE in its two sets of one-dimensional detectors, in the 17-25 keV energy range.

 

 

 

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SuperAGILE detects the new outburst of SAX J1750.8-2900 a hard X-rays

ATel #1428; L. Pacciani, E. Costa, E. Del Monte, I. Donnarumma, Y. Evangelista, M. Feroci, I. Lapshov, F. Lazzarotto, M. Rapisarda, P. Soffitta, A. Argan, A. Trois , M. Tavani, G. Pucella, F. D'Ammando, V. Vittorini (INAF/IASF Roma), A. Chen, S. Vercellone, A. Giuliani, S. Mereghetti, A. Pellizzoni, F. Perotti, F. Fornari, M. Fiorini, P. Caraveo (INAF/IASF Milano), A. Bulgarelli, F. Gianotti, M. Trifoglio, G. Di Cocco, C. Labanti, F. Fuschino, M. Marisaldi, M. Galli, (INAF/IASF Bologna), G. Barbiellini, F. Longo, E. Vallazza (INFN Trieste), P. Picozza, A. Morselli (INFN Roma-2), M. Prest (Universita` dell'Insubria), P. Lipari, D. Zanello (INFN Roma-1), F. Mauri (INFN Pavia) and C Pittori, F. Verrecchia, B. Preger, L.A. Antonelli, P. Giommi (ASDC) and L. Salotti (ASI)
on 17 Mar 2008; 15:53 UT
Password Certification: Marco Feroci (marco.feroci@iasf-roma.inaf.it)

Subjects: X-ray, Binaries, Neutron Stars, Transients
Referred to by ATel #: 1431

The neutron star transient SAX J1750.8-2900, detected in a new outburst by RXTE/PCA on March 15th (ATel #1425), is currently within the field of view of SuperAGILE, which is pointing at the Galactic Center region. The 20-60 keV average flux detected by SuperAGILE during the time period between 2008-03-16 13:00 UT and 2008-03-17 08:00 UT is approximately 80 mCrab. The AGILE monitoring of the same sky region will continue for the next two weeks.

 

 

 

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AGILE gamma-ray detection of a variable source in the Musca region

ATel #1394; C. Pittori, F. Verrecchia, P. Santolamazza, B. Preger, P. Giommi (ASDC), S. Vercellone, A. Chen, A. Giuliani, S. Mereghetti, A. Pellizzoni, F. Perotti, F. Fornari, M. Fiorini, P. Caraveo, A. Zambra (INAF/IASF Milano), A. Bulgarelli, F. Gianotti, M. Trifoglio, G. Di Cocco, C. Labanti, F. Fuschino, M. Marisaldi, M. Galli, (INAF/IASF Bologna), M. Tavani, G. Pucella, F. D'Ammando, V. Vittorini, E. Costa, M. Feroci, I.Donnarumma, L. Pacciani,E. Del Monte, F. Lazzarotto, P. Soffitta, Y. Evangelista, I. Lapshov, M. Rapisarda, A. Argan, A. Trois , G. De Paris (INAF/IASF Roma), G. Barbiellini, F. Longo (INFN Trieste), P. Picozza, A. Morselli (INFN Roma-2), M. Prest, E. Vallazza (Universita` dell'Insubria), P. Lipari, D. Zanello (INFN Roma-1), F. Mauri (INFN Pavia) and L. Salotti (ASI)
on 22 Feb 2008; 17:13 UT
Password Certification: Stefano Vercellone (stefano@iasf-milano.inaf.it)

Subjects: X-ray, Gamma Ray, Transients
Referred to by ATel #: 1419

The AGILE satellite, currently in a Cycle-1 pointing centered approximately in the Musca region, during the observing period that started on 2008-02-14 12:00 UT, detected significant and variable gamma-ray emission from the Galactic plane from a source positionally consistent with 3EG J1410-6147. The AGILE Quicklook Analysis (AQA) provides the source positional error box that is centered at Galactic coordinates l = 312.2 deg, b = -0.3 deg, and has a AQA radius of about 0.5 degree. A preliminary maximum likelihood analysis of the AGILE-GRID (Gamma-Ray Imaging Detector) data obtained between 2008-02-21 06:00 UT and 2008-02-22 07:30 UT for photon energies above 100 MeV results in a detection significance of about 4 sigma. A preliminary analysis of the Super-AGILE data over the same time period and the same sky region does not show any counterpart in the 20-60 keV energy range. The 3-sigma upper limit on the one-day average flux is 25 mCrab. We strongly encourage multi-frequency observations of the field of the gamma-ray source detected by AGILE in an active gamma-ray flaring state.

 

 

 

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SuperAGILE limits on the hard X-ray flux of the AGILE bright gamma-ray transient in the Cygnus field

ATel #1320;F. Lazzarotto, Y. Evangelista, I. Donnarumma, L. Pacciani,E. Costa, E. Del Monte, M. Feroci, I. Lapshov, M. Rapisarda, P. Soffitta, A. Argan, A. Trois , M. Tavani, G. Pucella, F. D'Ammando, V. Vittorini (INAF/IASF Roma), A. Chen, S. Vercellone, A. Giuliani, S. Mereghetti, A. Pellizzoni, F. Perotti, F. Fornari, M. Fiorini, P. Caraveo (INAF/IASF Milano), A. Bulgarelli, F. Gianotti, M. Trifoglio, G. Di Cocco, C. Labanti, F. Fuschino, M. Marisaldi, M. Galli, (INAF/IASF Bologna), G. Barbiellini, F. Longo, E. Vallazza (INFN Trieste), P. Picozza, A. Morselli (INFN Roma-2), M. Prest (Universita` dell'Insubria), P. Lipari, D. Zanello (INFN Roma-1), F. Mauri (INFN Pavia) and C. Pittori, F. Verrecchia, B. Preger, L.A. Antonelli, P. Giommi (ASDC) and L. Salotti (ASI)
on 4 Dec 2007; 17:35 UT
Password Certification: Stefano Vercellone (stefano@iasf-milano.inaf.it)

Subjects: X-ray, Gamma Ray, Transients

We analyzed the hard X-ray (20-60 keV) data collected by SuperAGILE between 2007-11-09 and 2007-11-23 from the sky region including the bright and rapid gamma-ray transient detected by the AGILE-GRID (Chen et al., ATel #1308). Due to the satellite attitude, one of the two SuperAGILE coordinates is confused by the source EXO 2030+375 and we considered safer to exclude it from this analysis. Using the other coordinate only (half of the SuperAGILE effective area), we do not find any significant X-ray emission at the position of the gamma-ray transient, neither on the orbital, daily or weekly timescales. The SuperAGILE 3-sigma upper limits are 40 mCrab (orbital), 21 mCrab (daily) and 12 mCrab (weekly), including a significant systematics at exposures of one day (50%) and one week (60%), due to the yet preliminary status of the experiment in-flight calibrations.

 

 

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AGILE gamma-ray detection of a strongly variable source in the Cygnus region

ATel #1308; A. Chen, S. Vercellone, A. Giuliani, S. Mereghetti, A. Pellizzoni, F. Perotti, F. Fornari, M. Fiorini, P. Caraveo, A. Zambra (INAF/IASF Milano), A. Bulgarelli, F. Gianotti, M. Trifoglio, G. Di Cocco, C. Labanti, F. Fuschino, M. Marisaldi, M. Galli, (INAF/IASF Bologna), M. Tavani, G. Pucella, F. D'Ammando, V. Vittorini, E. Costa, M. Feroci, I. Donnarumma, L. Pacciani, E. Del Monte, F. Lazzarotto, P. Soffitta, Y. Evangelista, I. Lapshov, M. Rapisarda, A. Argan, A. Trois , G. De Paris (INAF/IASF Roma), G. Barbiellini, F. Longo (INFN Trieste), P. Picozza, A. Morselli (INFN Roma-2), M. Prest, E. Vallazza (Universita` dell'Insubria), P. Lipari, D. Zanello (INFN Roma-1), F. Mauri (INFN Pavia) and P. Giommi, C. Pittori, L. A. Antonelli, D. Gasparrini, S. Cutini, F. Verrecchia (ASDC) and L. Salotti (ASI)

on 27 Nov 2007; 19:19 UT
Password Certification: Andrew Chen (chen@iasf-milano.inaf.it)

Subjects: Gamma Ray, >GeV, Transients

The AGILE satellite, currently in its Science Verification Phase, during the Observing Block that started on 2007-11-02 12:00 UT, detected significant and strongly variable gamma-ray emission from the Cygnus region lasting only about 1 day.

The variable source positional error box is centered at Galactic coordinates l = 75.0 deg, b = -0.4 deg, and has a radius of about 1 degree.

A preliminary maximum likelihood analysis of the AGILE-GRID (Gamma-Ray Imaging Detector) data obtained between 2007-11-23 03:58:55 and 2007-11-24 03:58:55 for photon energies above 100 MeV results in a detection significance of over 5 sigma.

A very preliminary analysis of the SuperAGILE data over the same time period and the same sky region does not show any counterpart in the 20-60 keV energy range with an average flux brighter than approximately 30 mCrab.

We strongly encourage multi-frequency observations of the field of the gamma-ray source detected by AGILE.

 

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AGILE detection of day-to-day gamma-ray variability from Blazar 3C 454.3

ATel #1300; G. Pucella, M. Tavani, F. D'Ammando, V. Vittorini, E. Costa, M. Feroci, I. Donnarumma, L. Pacciani, E. Del Monte, F. Lazzarotto, P. Soffitta, Y. Evangelista, I. Lapshov, M. Rapisarda, A. Argan, A. Trois , G. De Paris (INAF/IASF Roma), S. Vercellone, A. Chen, A. Giuliani, S. Mereghetti, A. Pellizzoni, F. Perotti, F. Fornari, M. Fiorini, P. Caraveo, A. Zambra (INAF/IASF Milano), A. Bulgarelli, F. Gianotti, M. Trifoglio, G. Di Cocco, C. Labanti, F. Fuschino, M. Marisaldi, M. Galli, (INAF/IASF Bologna), G. Barbiellini, F. Longo (INFN Trieste), P. Picozza, A. Morselli (INFN Roma-2), M. Prest, E. Vallazza (Universita` dell'Insubria), P. Lipari, D. Zanello (INFN Roma-1), F. Mauri (INFN Pavia) and P. Giommi, C. Pittori, L. A. Antonelli, D. Gasparrini, S. Cutini, F. Verrecchia (ASDC) and L. Salotti (ASI)
on 22 Nov 2007; 18:33 UT
Password Certification: Andrew Chen (chen@iasf-milano.inaf.it)

Subjects: Gamma Ray, >GeV, AGN, Quasars

The AGILE satellite, currently in its Science Verification Phase, during the Observing Block that started on 2007-11-02 12:00 UT, detected significant gamma-ray emission from a source coincident with the blazar 3C 454.3, as reported in ATEL #1278. The source continues to be active in > 100 MeV gamma rays, showing variability on day-to-day time scales, with particular activity within the last two days. We strongly encourage continued multi-frequency observations of the field of the gamma-ray source detected by AGILE.

 

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AGILE detection of a gamma-ray source coincident with Blazar 3C 454.3
ATel #1278; A. Chen, S. Vercellone, A. Giuliani, S. Mereghetti, A. Pellizzoni, F. Perotti, F. Fornari, M. Fiorini, P. Caraveo, A. Zambra (INAF/IASF Milano), A. Bulgarelli, F. Gianotti, M. Trifoglio, G. Di Cocco, C. Labanti, F. Fuschino, M. Marisaldi, M. Galli, (INAF/IASF Bologna), M. Tavani, G. Pucella, F. D'Ammando, V. Vittorini, E. Costa, M. Feroci, I. Donnarumma, L. Pacciani, E. Del Monte, F. Lazzarotto, P. Soffitta, Y. Evangelista, I. Lapshov, M. Rapisarda, A. Argan, A. Trois , G. De Paris (INAF/IASF Roma), G. Barbiellini, F. Longo (INFN Trieste), P. Picozza, A. Morselli (INFN Roma-2), M. Prest, E. Vallazza (Universita` dell'Insubria), P. Lipari, D. Zanello (INFN Roma-1), F. Mauri (INFN Pavia) and P. Giommi, C. Pittori, L. A. Antonelli, D. Gasparrini, S. Cutini, F. Verrecchia (ASDC) and L. Salotti (ASI)

on 14 Nov 2007; 10:07 UT
Password Certification: Andrew Chen (chen@iasf-milano.inaf.it)
Subjects: Gamma Ray, >GeV, AGN, Quasars

The AGILE satellite, currently in its Science Verification Phase, during the Observing Block that started on 2007-11-02 12:00 UT, detected significant gamma-ray emission from a source coincident with the blazar 3C 454.3.

A preliminary maximum likelihood analysis of the AGILE-GRID (Gamma-Ray Imaging Detector) data obtained between 2007-11-02 13:50 UT and 2007-11-12 17:01 UT for photon energies above 100 MeV results in a detection significance of about 5.4 sigma, slightly over our current, conservatively estimated detection threshold.

Considering that the in-flight calibration of the GRID is still ongoing, and despite the fact that the source was more than 40 degrees off-axis, a region in the field of view whose calibration is still highly uncertain, we encourage multi-frequency observations of the field of the gamma-ray source detected by AGILE. The AGILE pointing of the Galactic plane region that includes this gamma-ray source will continue until 2007-12-01 12:00 UT.

 

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AGILE detection of a gamma-ray source possibly associated with Blazar TXS 0716+714

ATel #1221; A. Giuliani, S. Vercellone, A. Chen, S. Mereghetti, A. Pellizzoni, F. Perotti, F. Fornari, M. Fiorini, P. Caraveo, A. Zambra (INAF/IASF Milano), A. Bulgarelli, F. Gianotti, M. Trifoglio, G. Di Cocco, C. Labanti, F. Fuschino, M. Marisaldi, M. Galli, (INAF/IASF Bologna), M. Tavani, G. Pucella, F. D'Ammando, V. Vittorini, E. Costa, M. Feroci, I. Donnarumma, L. Pacciani, E. Del Monte, F. Lazzarotto, P. Soffitta, Y. Evangelista, I. Lapshov, M. Rapisarda, A. Argan, A. Trois , G. De Paris (INAF/IASF Roma), G. Barbiellini, F. Longo (INFN Trieste), P. Picozza, A. Morselli (INFN Roma-2), M. Prest, E. Vallazza (Universita` dell'Insubria), P. Lipari, D. Zanello (INFN Roma-1), F. Mauri (INFN Pavia) and P. Giommi, C. Pittori, L. A. Antonelli, D. Gasparrini, S. Cutini, F. Verrecchia (ASDC) and L. Salotti (ASI)
on 21 Sep 2007; 15:53 UT
Password Certification: Stefano Vercellone (stefano@iasf-milano.inaf.it)

Subjects: Gamma Ray, AGN, Quasars
Referred to by ATel #: 1223

The AGILE satellite, currently in its science performance verification phase, during the Observing Block that started on 2007-09-04 12:00 UT, detected significant gamma-ray emission from a source possibly associated with blazar TXS 0716+714.

A preliminary maximum likelihood analysis of the AGILE-GRID (Gamma-Ray Imaging Detector) data obtained between 2007-09-10 13:50 UT and 2007-09-20 10:13 UT for photon energies above 100 MeV results in a detection significance of about 8 sigma. The positional error box, that does not yet take into account possible systematic effects, is centered at Galactic coordinates l = 143.8 deg, b = 27.6 deg. The 95% confidence level contour has a radius of about 0.4 degrees. The blazar TXS 0716+714, that has been associated with the gamma-ray source 3EG J0721+7120, lies at a distance of 0.44 degrees from the best fit position of the gamma-ray source. We therefore tentatively associate the AGILE source with this blazar.

Considering that the in-flight calibration of the GRID is still ongoing, and despite the preliminary GRID positioning capability at off-axis angles (20 to 40 deg for this observation), we strongly encourage multi-frequency observations of the field of the gamma-ray source detected by AGILE. The AGILE pointing of the Galactic plane region that includes this gamma-ray source will continue until 2007-09-23 12:00 UT.

 

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AGILE detection of a gamma-ray source off the Galactic Plane

ATel #1199; A. Bulgarelli (INAF/IASF Bologna), S. Vercellone, A. Giuliani, A. Chen, S. Mereghetti, A. Pellizzoni, F. Perotti, F. Fornari, M. Fiorini, P. Caraveo, A. Zambra (INAF/IASF Milano), M. Tavani, G. Pucella, F. D'Ammando, V. Vittorini, E. Costa, M. Feroci, I. Donnarumma, L. Pacciani, E. Del Monte, F. Lazzarotto, P. Soffitta, Y. Evangelista, I. Lapshov, M. Rapisarda, A. Argan, A. Trois (INAF/IASF Roma), G. Barbiellini, F. Longo (INFN Trieste), G. Di Cocco, C. Labanti, F. Fuschino, M. Marisaldi, M. Galli, F. Gianotti, M. Trifoglio (INAF/IASF Bologna), P. Picozza, A. Morselli (INFN Roma-2), M. Prest, E. Vallazza (Universita` dell'Insubria), P. Lipari (INFN Roma-1) and P. Giommi, C. Pittori, L. A. Antonelli, D. Gasparrini, S. Cutini, F. Verrecchia (ASDC) and L. Salotti (ASI)
on 31 Aug 2007; 16:53 UT
Password Certification: Stefano Vercellone (stefano@iasf-milano.inaf.it)

Subjects: Gamma Ray, AGN, Quasars, Transients
Referred to by ATel #: 1204

The AGILE satellite, currently in its science performance verification phase, during an observation centered near the Galactic plane (l=334.44, b=10.06) that started on 2007-08-27 12:00 UT, detected significant gamma-ray emission from a source at approximately 33 degrees off the AGILE pointing direction. A preliminary maximum likelihood analysis of the AGILE-GRID (Gamma-Ray Imaging Detector) data obtained between 2007-08-27 14:48 UT and 2007-08-30 10:50 UT for photon energies above 100 MeV results in a detection significance of about 4 sigma. The positional error box derived from our preliminary maximum likelihood analysis (that does not, as yet, take into account possible systematic effects) results in a 95% contour level centered at the position l = 351.1, b = 39.7 with a radius of about 0.5 degrees. We note that this position is marginally consistent with the radio position of the blazar TXS 1510-089 that has been associated with the gamma-ray source 3EG J1512-0849. Considering that the in-flight calibration of the GRID is still ongoing, and despite the preliminary GRID positioning capability at substantial off-axis angles, we strongly encourage multi-frequency observations of the field of the gamma-ray source detected by AGILE. The AGILE pointing of the Galactic plane region that includes this gamma-ray source will continue until 2007-09-01 12:00 UT.

 

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AGILE pointing at 3C 454.3: end of the observations and preliminary results.

ATel #1167; A. Bulgarelli (INAF/IASF Bologna), A. Chen, S. Vercellone, A. Giuliani, S. Mereghetti, A. Pellizzoni, F. Perotti, F. Fornari, F. Fiorini (INAF/IASF Milano), G. Pucella, F. D'Ammando (INAF/IASF Roma), F. Longo (INFN Trieste), M. Prest, E. Vallazza (INFN Insubria), M. Tavani (INAF/IASF Roma), G. Barbiellini (INFN Trieste), P. Caraveo (INAF/IASF Milano), E. Costa (INAF/IASF Roma), G. Di Cocco (INAF/IASF Bologna), P. Picozza (INFN Roma), M. Feroci, I. Donnarumma, L. Pacciani, E. Del Monte, F. Lazzarotto, P. Soffitta, Y. Evangelista, I. Lapshov, M. Rapisarda (INAF/IASF Roma), C. Labanti, F. Fuschino, M. Marisaldi, M. Galli, F. Gianotti, M. Trifoglio (INAF/IASF Bologna), A. Argan, A. Trois (INAF/IASF Roma), A. Zambra (INAF/IASF Milano), Lipari (INFN Roma), on behalf of the AGILE Team and P. Giommi, C. Pittori, L. A. Antonelli, D. Gasparrini, S. Cutini, F. Verrecchia (ASDC) and L. Salotti (ASI)
on 2 Aug 2007; 15:52 UT
Password Certification: Stefano Vercellone (stefano@iasf-milano.inaf.it)

Subjects: Gamma Ray, AGN, Transients

The AGILE satellite, currently in the scientific performance verification phase, has observed the 3C 454.3 field starting on 2007-07-24 14:30 UT, and ending on 2007-07-30 11:40 UT. The AGILE repointing followed a significant flaring activity of this blazar, as detected in the optical and X-ray bands. AGILE subsequently detected the source in the gamma-ray energy band during the early phase of the observation (see ATel #1160).

Based on all the data accumulated in 5.8 days by the AGILE GRID (Gamma-Ray Imaging Detector) on 3C 454.3, and considering that the in-flight calibration is still ongoing, the source detection significance turns out to be equal to 9.9 sigma as derived from a maximum likelihood analysis (note that this significance does not take systematic errors into account). The average flux is consistent, within the uncertainties, with the previously reported AGILE flux estimate (ATel. #1160). A time variability analysis is in progress.

 

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AGILE gamma-ray detection of the Blazar 3C 454.3

ATel #1160; S. Vercellone, A. Chen, A. Giuliani, A. Pellizzoni, S. Mereghetti, F. Fornari, P. Caraveo, F. Perotti, M. Fiorini (INAF/IASF Milano), A. Bulgarelli, G. Di Cocco, C. Labanti, M. Marisaldi, F. Fuschino, M. Galli, F. Gianotti, M. Trifoglio (INAF/IASF Bologna), M. Tavani, G. Pucella, F. D'Ammando, E. Costa, M. Feroci, I. Donnarumma, L. Pacciani, E. Del Monte, A. Argan, A.Trois, (INAF/IASF Roma), M. Prest, E. Vallazza (INFN-Como), G. Picozza, P. Lipari (INFN-Roma), F. Longo, G. Barbiellini (INFN-Trieste) on behalf of the AGILE Team and P. Giommi, C. Pittori, L.A. Antonelli, D. Gasparrini, S. Cutini, G. Fanari, F. Verrecchia (ASDC) and L. Salotti (ASI)
on 27 Jul 2007; 15:45 UT
Password Certification: Adamantia Paizis (ada@iasf-milano.inaf.it)

Subjects: Gamma Ray, AGN, Transients
Referred to by ATel #: 1167

The AGILE satellite, currently in the science performance verification phase, started to observe the 3C454.3 field on July 24, 2007, following the significant flaring activity of this blazar recently detected in the optical and X-ray energy bands. A gamma-ray source positionally consistent with 3C 454.3 is detected with a maximum likelihood analysis giving a significance of 4.9 sigma in the AGILE GRID (Gamma-Ray Imaging Detector) data acquired between 2007-07-24 14:30 UT and 2007-07-27 05:27 UT. Due to satellite constraints, 3C 454.3 is about 36 degrees off-axis. Considering that the in-flight calibration of the GRID is still ongoing, we can only provide at this moment a preliminary estimate of the gamma-ray flux of (3+/-1)*10E-6 ph/cm2/s for E>100 MeV. AGILE will point at the 3C 454.3 field until July 30, 12:00 UT. Multifrequency observations of the source are encouraged.