GCN Circular 15479
Subject
GRB 131108A: AGILE/GRID observation
Date
2013-11-09T21:41:41Z (11 years ago)
From
Andrea Giuliani at IASF/INAF <giuliani@iasf-milano.inaf.it>
A. Giuliani (INAF/IASF-Mi), F. Longo (University of Trieste and INFN Trieste),
F. Verrecchia, C. Pittori (ASDC and INAF/OAR), M. Marisaldi, F. Fuschino
(INAF/IASF-Bo), F. Lucarelli (ASDC and INAF/OAR),
E. Del Monte, F. Lazzarotto, I. Donnarumma, Y. Evangelista, M. Feroci, L.
Pacciani, P. Soffitta, E. Costa,
I. Lapshov, M. Rapisarda (INAF/IAPS Rome), G. Barbiellini, (INFN Trieste),
A. Bulgarelli, F. Gianotti, M. Trifoglio, G. Di Cocco, C. Labanti, V.
Fioretti, M. Galli (INAF/IASF-Bo),
A. Chen, S. Mereghetti, F. Perotti, P. Caraveo (INAF/IASF-Mi),
M. Cardillo, E. Striani, M. Tavani (INAF/IAPS Rome, and Univ. Roma Tor Vergata),
A. Argan, G. Piano, S. Sabatini, V. Vittorini (INAF/IAPS Rome),
G. Pucella (ENEA Frascati), A. Pellizzoni, A. Trois (INAF/OA Cagliari),
M. Pilia (ASTRON), S. Vercellone (INAF/IASF-Pa),
P. W. Cattaneo, A. Rappoldi (INFN Pavia), A. Morselli, P. Picozza (INFN Roma-2),
M. Prest, E. Vallazza (Universita` dell'Insubria),
P. Lipari, D. Zanello (INFN Roma-1), P. Giommi (ASI), and G. Valentini (ASI),
on behalf of the AGILE Team, report:
GRB 131108A (GCN 15464) transited in the field of view of AGILE
approximately between t0-20 and t0+150 sec (with t0 = 08:41:55 UT).
A preliminary analysis of the Gamma-Ray Imaging Detector (GRID) data in
temporal and spatial coincidence with the GRB shows a significant excess of
gamma-ray events above 30 MeV at the location of the event.
During the first 80 seconds after t0 the GRID instrument detected 66
photons compatible with the GRB, most of which below 100 MeV, corresponding
to a fluence of 2.56 +- 0.32 1e-5 erg / cm^2 in the energy band 30 MeV -
1 GeV.
The energy distribution of photons in the same energy band is compatible
with a power-law of index -2.35 +-0.2 .
An analysis of the AGILE/MCAL data is also in progress.
More observations of this interesting burst are strongly encouraged.
This message may be cited.
[GCN OPS NOTE(09nov13): This was delayed by ~1 hour because the submitor's
new account had to added to the Circulars list.]