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
Credential Certification: Marco Feroci (email@example.com)
Subjects: X-ray, Gamma Ray, Soft Gamma-ray Repeater
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.