TITLE:   GCN CIRCULAR
NUMBER:  31786
SUBJECT: GRB 220323A: AstroSat CZTI detection
DATE:    22/03/25 06:39:21 GMT
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 a short GRB 220323A which was
also detected by Fermi - GBM (GCN 31782) and AGILE/MCAL (Ursi et al.,
GCN 31784). 

The source was clearly detected in the 20-200 keV energy range. The
light curve peaks at 2022-03-23 12:10:10.55 UT. The measured peak count
rate associated with the burst is 1120 (+888, -4) counts/s above the
background in the combined data of three quadrants, with a total of 141
(+48, -50) counts. The local mean background count rate was 386 (+13,
-34) counts/s. Using cumulative rates, we measure a T90 of 0.32 (+0.22,
-0.15) s. 

It was also 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 [1]. 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. 

Links:
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[1] http://astrosat.iucaa.in/czti/?q=grb