GCN Circular 33772
Subject
GRB 230510B: AstroSat CZTI detection
Date
2023-05-11T15:03:27Z (a year ago)
From
Gaurav Waratkar at IIT Bombay <gauravwaratkar@iitb.ac.in>
P K. Navaneeth (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 long GRB 230510B which was also detected by Fermi (Fermi GBM Team, GCN Circ. 33759), MAXI/GSC (Nakajima et al., GCN Circ. 33760), and CALET (Marrocchesi et al., GCN Circ. 33763).
The source was detected in the 20-200 keV energy range. The light curve showed multiple peaks of emission with the strongest peak at 2023-05-10 21:21:52.50 UTC. The measured peak count rate associated with the burst is 98 (+43, -2) counts/s above the background in the combined data of three quadrants (out of four), with a total of 4971 (+1144, -1220) counts. The local mean background count rate was 313 (+1, -1) counts/s. Using cumulative rates, we measure a T90 of 270 (+36, -58) s.
The source was also clearly detected in the CsI anticoincidence (Veto) detector in the 100-500 keV energy range.The light curve showed multiple peaks of emission with the strongest peak at 2023-05-10 21:21:52.50 UTC. The measured peak count rate associated with the burst is 316 (+77, -19) counts/s above the background in the combined data of all quadrants, with a total of 11559 (+2752, -3027) counts. The local mean background count rate was 1315 (+3, -3) counts/s. We measure a T90 of 202 (+36, -10) s from the cumulative Veto light curve.
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.
CZTI GRB detections are reported regularly on the payload site at:
http://astrosat.iucaa.in/czti/?q=grb