{
  "bibcode": "2023GCN.33400....1N",
  "body": "P K. Navaneeth (IUCAA), R. Gopalakrishnan (IUCAA), G. Waratkar (IITB), \nA. Vibhute (IUCAA), V. Bhalerao (IITB), D. Bhattacharya (Ashoka \nUniversity/IUCAA), A. R. Rao (IUCAA/TIFR), and S. Vadawale (PRL) report \non behalf of the AstroSat CZTI collaboration:\n\nAnalysis of AstroSat CZTI data with the CIFT framework (Sharma et al., \n2021, JApA, 42, 73) showed the detection of a GRB 230304B which was also \ndetected by Fermi GBM (GCN Circ. 33396) and GRBAlpha (Dafcikova et al., \nGCN Circ. 33398).\n\nThe source was clearly detected in the 20-200 keV energy range. The \nlight curve showed multiple peaks of emission with the strongest peak at \n2023-03-04 14:35:49.5 UTC. The measured peak count rate associated with \nthe burst is 640 (+51, -54) counts/s above the background in the \ncombined data of three quadrants (out of four), with a total of 4194 \n(+351, -404) counts. The local mean background count rate was 319 (+3, \n-5) counts/s. Using cumulative rates, we measure a T90 of 22.11 (+3, -4) \ns.\n\nIt was also clearly detected in the CsI anticoincidence (Veto) detector \nin the 100-500 keV energy range. The light curve peaks at 2023-03-04 \n14:35:48.9 UTC. The measured peak count rate is 1900 (+90, -100) \ncounts/s above the background in the combined Veto data of all \nquadrants, with a total of 12984 (+592, -623) counts. The local mean \nbackground count rate was 1314 (+7, -6) counts/s. We measure a T90 of \n20.5 (+2, -2) s from the cumulative Veto light curve.\n\nCZTI GRB detections are reported regularly on the payload site at \nhttp://astrosat.iucaa.in/czti/?q=grb. CZTI is built by a TIFR-led \nconsortium of institutes across India, including VSSC, URSC, IUCAA, SAC, \nand PRL. The Indian Space Research Organisation funded, managed, and \nfacilitated the project.",
  "circularId": 33400,
  "createdOn": 1678084788000,
  "email": "gauravwaratkar@iitb.ac.in",
  "subject": "GRB 230304B: AstroSat CZTI detection",
  "submitter": "Gaurav Waratkar at IIT,Bombay  <gauravwaratkar@iitb.ac.in>",
  "eventId": "GRB 230304B"
}