[vsnet-grb-info 27264] GRB 210124B: AstroSat CZTI detection

[GCN Circulars]

TITLE:   GCN CIRCULAR
NUMBER:  29367
SUBJECT: GRB 210124B: AstroSat CZTI detection
DATE:    21/01/29 06:12:31 GMT
FROM:    Gaurav Waratkar at IIT,Bombay  <gauravwaratkar at iitb.ac.in>

D. Nadella (NITK), G. Waratkar (IITB), A. Vibhute (IUCAA), S. Gupta
(IUCAA), P. Sawant (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,
2020, arxiv:2011.07067) showed detection of the short GRB 210124B, which
was also detected by Insight-HXMT/HE (GCN #29353) & Konus-Wind (GCN
#29357).

The source was clearly detected in the 20-200 keV energy range in all
four quadrants. Quadrant D was noisy, and we excluded it from further
analysis. The light curve showed multiple peaks of emission with the
strongest peak at 2021-01-24 13:23:45.43 UT. The measured peak count
rate associated with the burst is 2348 (+928, -540) cts/s above the
background in the combined data of three quadrants, with a total of 88
(+52, -26) cts. The local mean background count rate was 362 (+2, -25)
cts/s. Using cumulative rates, we measure a T90 of 0.07 (+0.35, -0.04)
s.

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.