{
  "bibcode": "2021GCN.29437....1W",
  "body": "G. Waratkar (IITB), D. Nadella (NITK), V. Shenoy (IITB), A. Vibhute \n(IUCAA), S. Gupta (IUCAA), P. Sawant (IUCAA), V. Bhalerao (IITB), D. \nBhattacharya (IUCAA), A. R. Rao (IUCAA/TIFR), and S. Vadawale (PRL) \nreport on behalf of the AstroSat CZTI collaboration:\n\nAnalysis of AstroSat CZTI data with the CIFT framework (Sharma et al, \n2020, arxiv:2011.07067) showed detection of a bright long GRB 210207B, \nwhich was also detected by Swift (BAT - GCN #29420, #29435, XRT - \n#29422, #29427) Konus-Wind (GCN #29426), AGILE-MCAL (GCN #29428) and \nInsight-HXMT/HE (GCN #29434).\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 \n2021-02-07 21:52:49 UT in all four quadrants. The measured peak count \nrate associated with the burst is 517 (+52, -57) cts/s above the \nbackground in the combined data of four quadrants, with a total of 3408 \n(+384, -451) cts. The local mean background count rate was 560 (+3, -3) \ncts/s. Using cumulative rates, we measure a T90 of 42 (+10, -2) s.\n\nIt was also clearly detected in the CsI anticoincidence (Veto) detector \nin the 100-500 keV energy range. The light curve showed multiple peaks \nof emission with the strongest peak at 2021-02-07 21:52:48 UT. The \nmeasured peak count rate is 994 (+88, -93) cts/s above the background in \nthe combined Veto data of four quadrants, with a total of 6364 (+849, \n-894) cts. The local mean background count rate was 1931.8 (+5, -5) \ncts/s. We measure a T90 of 44 (+9, -4) s from the cumulative Veto light \ncurve.\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, ISAC, IUCAA, SAC \nand PRL. The Indian Space Research Organisation funded, managed and \nfacilitated the project.",
  "circularId": 29437,
  "createdOn": 1612870934000,
  "email": "gauravwaratkar@iitb.ac.in",
  "subject": "GRB 210207B: AstroSat CZTI detection",
  "submitter": "Gaurav Waratkar at IIT,Bombay  <gauravwaratkar@iitb.ac.in>",
  "eventId": "GRB 210207B"
}