GCN Circular 32028
Subject
GRB 220511A: AstroSat CZTI detection
Date
2022-05-12T11:33:37Z (2 years ago)
From
Gaurav Waratkar at IIT,Bombay <gauravwaratkar@iitb.ac.in>
R. Gopalakrishnan (IUCAA), V. Prasad (IUCAA), G. Waratkar (IITB), A.
Vibhute (IUCAA), V. Bhalerao (IITB), D. Bhattacharya (IUCAA), A. R. Rao
(IUCAA/TIFR), and S. Vadawale (PRL) report on behalf of the AstroSat
CZTI collaboration:
Analysis of AstroSat CZTI data with the CIFT framework (Sharma et al.,
2021, JApA, 42, 73) showed detection of GRB 220511A which was also
reported by Fermi GBM (GCN #32018), AGILE (Ursi et al., GCN #32021), and
Swift/BAT-GUANO (DeLaunay et al., GCN #32023).
The source was clearly detected in the 20-200 keV energy range. The
light curve peaked at 2022-05-11 13:41:57.45 UT. The measured peak count
rate associated with the burst is 802 (+197, -74) counts/s above the
background in the combined data of four quadrants, with a total of 1126
(+156, -184) counts. The local mean background count rate was 525 (+9,
-9) counts/s. Using cumulative rates, we measure a T90 of 1.8 (+0.8,
-0.4) s.
It was also clearly detected in the CsI anticoincidence (Veto) detector
in the 100-500 keV energy range.
CZTI GRB detections are reported regularly on the payload site at
http://astrosat.iucaa.in/czti/?q=grb. CZTI is built by a TIFR-led
consortium of institutes across India, including VSSC, ISAC, IUCAA, SAC,
and PRL. The Indian Space Research Organisation funded, managed, and
facilitated the project.