[vsnet-grb-info 25337] GRB 200325A: AGILE/MCAL observations

[GCN Circulars]

TITLE:   GCN CIRCULAR
NUMBER:  27437
SUBJECT: GRB 200325A: AGILE/MCAL observations
DATE:    20/03/25 11:17:45 GMT
FROM:    Alessandro Ursi at INAF/IAPS  <alessandro.ursi at gmail.com>

A. Ursi (INAF/IAPS), F. Verrecchia (SSDC, and INAF/OAR), M. Tavani
(INAF/IAPS, and Univ. Roma Tor Vergata), A. Argan, M. Cardillo, C.
Casentini, Y. Evangelista, G. Piano (INAF/IAPS), F. Lucarelli, C. Pittori,
(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 short burst GRB 200325A reported by
Fermi/GBM (GCN #27434), that also triggered the automatic AGILE
Mini-CALorimeter (MCAL) GRB alert Notice (ID 512191111), published at:
https://gcn.gsfc.nasa.gov/agile_mcal.html.

The event was detected by MCAL at T0 = 2020-03-25 03:18:31.71 +/- 0.01 s
(UTC), lasting ~1.2 s and releasing a total number of ~1000 counts in the
detector, above a background rate of ~580 Hz. The MCAL light curve can be
found at:
http://www.agilescienceapp.it/notices/GRB_067078_512191111.714274.png. The
time-integrated spectrum of the burst in 1.2 s can be fitted in the energy
range 0.4-10 MeV with a single power-law with ph.ind. = 1.72 -0.17/+0.20,
resulting in a reduced chi-squared of 1.03 (36 d.o.f.). The burst fluence
in the same energy range and time interval is 3.62e-06 erg/cm^2 (90%
confidence level).

The event localization according to Fermi/GBM, RA = 22.1, Dec = -29.1
(J2000; GCN #27434), is within the AGILE Gamma-Ray Imaging Detector (GRID)
Field-of-View, but no detection is obtained in the integrations (T0;T0+5s)
and (T0;T0+10s).

The AGILE-MCAL detector is a CsI detector with a 4 pi FoV, sensitive in the
energy range 0.4-100 MeV. Additional analysis of AGILE data is in progress.