GCN Circular 42200
Subject
GRB 251010A: AstroSat CZTI detection
Event
Date
2025-10-11T12:09:34Z (a day ago)
From
Anuraag Arya at IIT Bombay <aryaanuraag910@gmail.com>
Via
Web form
A. Goyal (IITB), A. Arya (IITB), U. Pathak (IITB), S. Salunke (IUCAA), M. Tembhurnikar (IUCAA), Harsha K. H. (IUCAA), G. Waratkar (Caltech/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 251010A which was also detected by Fermi GBM (GCN Circ. 42192).
The source was clearly detected in the CZT detectors in the 20-200 keV energy range. The light curve showed a broad peak of emission with the strongest peak at 2025-10-10 17:44:27.50 UTC. The measured peak count rate associated with the burst is 82 (+38, -8) counts/s above the background in the combined data of all quadrants, with a total of 628 (+155, -170) counts. The local mean background count rate was 292 (+3, -4) counts/s. Using cumulative rates, we measure a T90 of 9.5 (+3.1, -2.3) s.
The source was also faintly detected in the CsI anticoincidence (Veto) detector in the 100-500 keV energy range.
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