TITLE: GCN CIRCULAR NUMBER: 33401 SUBJECT: GRB 230304C: AstroSat CZTI detection DATE: 23/03/06 06:43:30 GMT FROM: Gaurav Waratkar at IIT,Bombay gauravwaratkar@iitb.ac.in
P K. Navaneeth (IUCAA), R. Gopalakrishnan (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 a GRB 230304C which was also detected by Fermi-GBM (Fermi GBM team, GCN Circ. 33397).
The source was clearly detected in the 20-200 keV energy range. The light curve peaks at 2023-03-04 22:01:39.5 UTC. The measured peak count rate associated with the burst is 93 (+42, -15) counts/s above the background in the combined data of three quadrants (out of four), with a total of 410 (+138, -140) counts. The local mean background count rate was 374 (+2, -3) counts/s. Using cumulative rates, we measure a T90 of 9.34 (+2, -4) 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. 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.