{
  "bibcode": "2020GCN.28345....1S",
  "body": "M. Stamatikos (OSU), S. D. Barthelmy (GSFC),\nJ. R. Cummings (CPI), H. A. Krimm (NSF),\nS. Laha (GSFC/UMBC), A. Y. Lien (GSFC/UMBC),\nC. B. Markwardt (GSFC), D. M. Palmer (LANL),\nT. Sakamoto (AGU), B. Sbarufatti (PSU),\nT. N. Ukwatta (LANL) (i.e. the Swift-BAT team):\n\nUsing the data set from T-239 to T+963 sec from the recent telemetry\ndownlink,\nwe report further analysis of BAT GRB 200901B (trigger #994165)\n(Sbarufatti et al., GCN Circ. 28337).  The BAT ground-calculated position is\nRA, Dec = 217.860, -38.704 deg which is\n   RA(J2000)  =  14h 31m 26.5s\n   Dec(J2000) = -38d 42' 15.2\"\nwith an uncertainty of 3.0 arcmin, (radius, sys+stat, 90% containment).\nThe partial coding was 82%.\n\nThe mask-weighted light curve shows some weak emission that\nstarts at ~T0 and ends at ~T+900 s. The available event data end\nat T+963 s, and the burst went out of the BAT FOV soon afterwards\n(~T+1000 s). T90 (15-350 keV) is 705.94 +- 148.71 sec (estimated error\nincluding systematics).\n\nThe time-averaged spectrum from T+32.14 to T+901.32 sec is best fit by a\npower law\nwith an exponential cutoff.  This fit gives a photon index 0.95 +- 0.63,\nand Epeak of 46.7 +- 8.6 keV (chi squared 61.80 for 56 d.o.f.).  For this\nmodel the total fluence in the 15-150 keV band is 4.3 +- 0.4 x 10^-6 erg/cm2\nand the 1-sec peak flux measured from T+68.62 sec in the 15-150 keV band is\n0.4 +- 0.2 ph/cm2/sec.  A fit to a simple power law gives a photon index\nof 1.95 +- 0.13 (chi squared 71.14 for 57 d.o.f.).  All the quoted errors\nare at the 90% confidence level.\n\nThe results of the batgrbproduct analysis are available at\nhttp://gcn.gsfc.nasa.gov/notices_s/994165/BA/",
  "circularId": 28345,
  "createdOn": 1599003712000,
  "email": "amy.y.lien@nasa.gov",
  "subject": "GRB 200901B: Swift-BAT refined analysis",
  "submitter": "Amy Lien at GSFC  <amy.y.lien@nasa.gov>",
  "eventId": "GRB 200901B"
}