GCN Circular 31575
Subject
GRB 220210A: AGILE detection
Date
2022-02-11T11:44:38Z (2 years ago)
From
Alessandro Ursi at INAF/IAPS <alessandro.ursi@gmail.com>
A. Ursi, L. Foffano (INAF/IAPS), F. Verrecchia, C. Pittori (SSDC, and
INAF/OAR), M. Tavani (INAF/IAPS, and Univ. Roma Tor Vergata), A. Argan, M.
Cardillo, C. Casentini, Y. Evangelista, E. Menegoni, G. Piano (INAF/IAPS),
F. Lucarelli (SSDC, and INAF/OAR), A. Bulgarelli, A. Di Piano, V. Fioretti,
F. Fuschino, N. Parmiggiani (INAF/OAS-Bologna), M. Marisaldi
(INAF/OAS-Bologna, and Bergen University), M. Pilia, A. Trois
(INAF/OA-Cagliari), I. Donnarumma (ASI), A. Giuliani (INAF/IASF-Mi), F.
Longo (Univ. Trieste and INFN Trieste), and P. Tempesta (TeleSpazio),
report on behalf of the AGILE Team:
The AGILE satellite detected the long GRB 220210A at T0 = 2022-02-10
23:56:38.40 +/- 0.01 s (UTC), reported by Fermi GBM (GCN #31568) and Swift
BAT (GCN #31572).
The burst is clearly visible in the AGILE scientific ratemeters of the
MiniCALorimeter (MCAL; 0.4-100 MeV) and AntiCoincidence (AC; 50-200 keV)
detectors. The event lasted about 1.9 s (in the 0.4-100 MeV energy range)
and it released a total number of 2110 counts in the MCAL detector (above a
background rate of 1230 Hz), and 3910 counts in the AC detector (above a
background rate of 3330 Hz). The AGILE ratemeters light curves can be found
at http://www.agilescienceapp.it/notices/GRB220210A_AGILE_RM.png .
The event also triggered a high time resolution MCAL data acquisition,
which released 1440 counts in the detector, above a background rate of 505
Hz. The time-integrated spectrum of the burst, from T0-0.19 s to T0+1.73 s,
can be fitted in the energy range 0.4-5 MeV with a power-law with ph.ind. =
-1.81 (-0.19,+0.21), resulting in a reduced chi-squared of 1.18 (36 d.o.f.)
and a fluence of 3.40e-06 erg/cm^2 (90% confidence level), in the same
energy range. The MCAL light curve can be found at
http://www.agilescienceapp.it/notices/076950_GRB_571622198.404213.png . At
the T0, the event was 15 deg off-axis.
Additional analysis of AGILE data is in progress. Automatic MCAL GRB alert
Notices can be found at: https://gcn.gsfc.nasa.gov/agile_mcal.html.