[vsnet-grb-info 26016] GRB 200716A: AGILE detection

[GCN Circulars]

TITLE:   GCN CIRCULAR
NUMBER:  28116
SUBJECT: GRB 200716A: AGILE detection
DATE:    20/07/16 12:56:58 GMT
FROM:    Alessandro Ursi at INAF/IAPS  <alessandro.ursi at gmail.com>

A. Ursi (INAF/IAPS), C. Pittori, F. Verrecchia (SSDC, and INAF/OAR), P.
Tempesta (TeleSpazio), M. Tavani (INAF/IAPS, and Univ. Roma Tor Vergata),
F. Lucarelli (SSDC, and INAF/OAR), A. Argan, M. Cardillo, C. Casentini, Y.
Evangelista, G. Piano (INAF/IAPS), A. Bulgarelli, V. Fioretti, F. Fuschino,
N. Parmiggiani (INAF/OAS-Bologna), M. Marisaldi (INAF/OAS-Bologna, and
Bergen University), F. Longo (Univ. Trieste and INFN Trieste), M. Pilia, A.
Trois (INAF/OA-Cagliari), I. Donnarumma (ASI), A. Giuliani (INAF/IASF-Mi),
report on behalf of the AGILE Team:

The AGILE satellite detected the long GRB 200716A reported by Fermi-GBM
(GCN #28109, trigger 616555602.759372 / 200716060), occurring at T0 =
2020-07-16 01:26:37 s (UTC).

The event is clearly visible in the scientific ratemeters (RMs) of the
SuperAGILE (SA, 18-60 keV), MiniCALorimeter (MCAL, 0.4-100 MeV), and
Anti-Coincidence (50-200 keV) detectors. Their light curves show a
multi-peaked profile, lasting about ~60 s and releasing ~4200 counts in the
SA detector (above a background rate of 60 Hz), ~75200 counts in the MCAL
detector (above a background rate of 1200 Hz), and ~225000 counts in the AC
detector (above a background rate of 3700 Hz). The AGILE RMs light curves
can be found at
http://www.agilescienceapp.it/notices/GRB200716A_AGILE_RMs.png .

The intense episode occurring at about T0 + 30 s triggered a MCAL high time
resolution data acquisition. The time-integrated spectrum of this episode
in ~7 s can be fitted in the energy range 0.4-10 MeV with a single
power-law with ph.ind. = 1.51 -0.05/+0.05, resulting in a reduced
chi-squared of 1.6 (48 d.o.f.). The episode fluence in the same energy
range and time interval is 3.5e-05 ergs/cm^2 (90% confidence level).

Additional analysis of AGILE data is in progress.