{
  "bibcode": "2023GCN.33482....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 long GRB 230304D which was \nalso detected by Fermi - GBM (Trigger Number - 699634754).\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 14:59:21.50 UTC. The measured peak count rate associated with \nthe burst is 313 (+45, -41) counts/s above the background in the \ncombined data of all quadrants, with a total of 2489 (+402, -322) \ncounts. The local mean background count rate was 443 (+2, -4) counts/s. \nUsing cumulative rates, we measure a T90 of 25.52 (+5, -2) s.\n\nThe source was also clearly detected in the CsI anticoincidence (Veto) \ndetector in the 100-500 keV energy range. The light curve showed \nmultiple peaks of emission with the strongest peak at 2023-03-04 \n14:59:20.91 UTC. The measured peak count rate associated with the burst \nis 390 (+67, -68) counts/s above the background in the combined data of \nall quadrants, with a total of 2433 (+610, -813) counts. The local mean \nbackground count rate was 1355 (+5, -5) counts/s. We measure a T90 of \n25.84 (+11, -17) s from the cumulative Veto light curve.\n\nCZTI is built by a TIFR-led consortium of institutes across India, \nincluding VSSC, URSC, IUCAA, SAC, and PRL. The Indian Space Research \nOrganisation funded, managed, and facilitated the project.\n\nCZTI GRB detections are reported regularly on the payload site at:\nhttp://astrosat.iucaa.in/czti/?q=grb",
  "circularId": 33482,
  "createdOn": 1678981988000,
  "email": "gauravwaratkar@iitb.ac.in",
  "subject": "GRB 230304D: AstroSat CZTI detection",
  "submitter": "Gaurav Waratkar at IIT,Bombay  <gauravwaratkar@iitb.ac.in>",
  "eventId": "GRB 230304D"
}