Skip to main content
Testing. You are viewing the public testing version of GCN. For the production version, go to https://gcn.nasa.gov.
New Announcement Feature, Code of Conduct, Circular Revisions. See news and announcements

GCN Circular 32441

Subject
GRB 220803A: AstroSat CZTI detection
Date
2022-08-04T11:25:47Z (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 (Ashoka 
University/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 the detection of GRB 220803A which was also 
detected by Fermi-GBM (TrigNum: 681212354) and was reported in an 
IPN_RAW Notice (contributed by Konus-Wind).

The source was clearly detected in the 20-200 keV energy range. The 
light curve showed multiple peaks of emission with the strongest peak at 
2022-08-03 09:39:10.15 UTC. The measured peak count rate associated with 
the burst is 714 (+175, -87) counts/s above the background in the 
combined data of three (out of four) quadrants, with a total of 935 
(+238, -226) counts. The local mean background count rate was 349 (+5, 
-6) counts/s. Using cumulative rates, we measure a T90 of 3.9 (+4.3, 
-1.0) s.

It was also clearly detected in the CsI anticoincidence (Veto) detector 
in the 100-500 keV energy range. The light curve peaks at 2022-08-03 
09:39:09.32 UTC. The measured peak count rate is 274 (+72, -76) counts/s 
above the background in the combined Veto data of all quadrants, with a 
total of 842 (+310, -330) counts. The local mean background count rate 
was 1691 (+8, -9) counts/s. We measure a T90 of 6 (+2, -4) s from the 
cumulative Veto light curve.

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, URSC, IUCAA, SAC, 
and PRL. The Indian Space Research Organisation funded, managed, and 
facilitated the project.
Looking for U.S. government information and services? Visit USA.gov