TITLE: GCN CIRCULAR NUMBER: 35503 SUBJECT: GRB 240107A: AstroSat CZTI detection DATE: 24/01/09 07:01:04 GMT FROM: Gaurav Waratkar at IIT Bombay <gauravwaratkar@iitb.ac.in> J. Joshi (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-duration GRB 240107A which was also detected by MAXI-GSC (Kurihara et al., GCN Circ. 35495). The source was 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 2024-01-07 19:16:32.4 UTC. The measured peak count rate associated with the burst is 191 (+66, -13) counts/s above the background in the combined data of three quadrants (out of four), with a total of 6807 (+1623, -1781) counts. The local mean background count rate was 1088 (+3, -4) counts/s. We measure a T90 of 160 (+18, -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 View this GCN Circular online at https://gcn.nasa.gov/circulars/35503. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0LW...