Skip to main content
Testing. You are viewing the public testing version of GCN. For the production version, go to
New Announcement Feature, Code of Conduct, Circular Revisions. See news and announcements

GCN Circular 31733

GRB 220308A: AGILE detection
2022-03-10T14:05:01Z (2 years ago)
Alessandro Ursi at INAF/IAPS <>
A. Ursi (INAF/IAPS), A. Di Piano (INAF/OAS-Bologna), 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,
L. Foffano, G. Piano (INAF/IAPS), F. Lucarelli (SSDC, and INAF/OAR), A.
Bulgarelli, 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), F. Longo (Univ. Trieste and INFN
Trieste), A. Giuliani (INAF/IASF-Mi), report on behalf of the AGILE Team:

The AGILE satellite detected the long GRB 220308A at T0 = 2022-03-08
05:43:08 (UTC), reported by INTEGRAL/SPI-ACS (trig#9761), Fermi/GBM
(trigger no.668410535), CALET (GCN #31719), Konus-Wind (GCN #31723),
Swift/BAT (GCN #31716), and triangulated by IPN (GCN #31715).

The burst is clearly visible in the AGILE scientific ratemeters of the
SuperAGILE (SA; 20-60 keV), MiniCALorimeter (MCAL; 0.4-100 MeV), and
AntiCoincidence (AC; 50-200 keV) detectors. The event lasted about 22 s and
it released a total number of 2675 counts in the SA detector (above a
background rate of 140 Hz), 54840 counts in the MCAL detector (above a
background rate of 1300 Hz), and 104080 counts in the AC detector (above a
background rate of 3680 Hz). The AGILE ratemeter light curves can be found
at .

The event also triggered a partial high time resolution MCAL data
acquisition, covering the main peaks of the burst, from T1 = 2022-03-08
05:43:08.21 s +/- 0.01 (UTC) to T2 = 2022-03-08 05:43:15.06 +/- 0.01 s
(UTC), and released 16490 counts in the detector, above a background rate
of 640 Hz. The time-integrated spectrum of the burst in this time interval
can be fitted in the energy range 0.4-10 MeV with a Band function with
alpha = -0.70 (frozen), beta = -2.45 (-0.11/+0.09), and Epeak = 760
(-98/+97) keV, resulting in a reduced chi-squared of 1.32 (47 d.o.f.) and a
fluence of 1.4e-04 ergs/cm^2 (90% confidence level), in the same energy
range. The MCAL light curve can be found at: .

Additional analysis of AGILE data is in progress. Automatic MCAL GRB alert
Notices can be found at: Please
note that in the MCAL notice #573803008 the T0 was affected by a temporal
shift of about +19.5 sec due to episodic automated ground software problems
which are then corrected offline.
Looking for U.S. government information and services? Visit