TITLE: GCN CIRCULAR NUMBER: 44404 SUBJECT: GRB 260424A: AstroSat CZTI detection of a long burst DATE: 26/04/24 10:37:58 GMT FROM: Anuraag Arya at IIT Bombay <aryaanuraag910@gmail.com> Harsha K. H. (IUCAA), M. Tembhurnikar (IUCAA), S. Salunke (IUCAA), A. Arya (IITB), A. Goyal (IITB), 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 a long GRB 260424A. The source was clearly detected in the CZT detectors in the 20-200 keV energy range. The light curve peaks at 2026-04-24 00:22:01.50 UTC. The measured peak count rate associated with the burst is 91 (+33, -12) counts/s above the background in the combined data of all quadrants, with a total of 756 (+197, -209) counts. We caution that there is a 0.3 s readout dead time in CZT data during the burst which affects the calculated total counts. The local mean background count rate was 242 (+2.5, -3) counts/s. Using cumulative rates, we measure a T90 of 12.6 (+9.23, -2.96) s. 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 data products like interactive and downloadable light curves for this GRB can be found at https://astrosat.iucaa.in/cift/cift_products/514686101.74/S514686101.74_deta... . All 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/44404. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0LW...