{
  "bibcode": "2021GCN.29537....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, we report further analysis of BAT GRB 210218A (trigger #1033328)\n(Sbarufatti et al., GCN Circ. 29529).  The BAT ground-calculated position is\nRA, Dec = 47.318, 35.322 deg which is\n   RA(J2000)  =  03h 09m 16.3s\n   Dec(J2000) = +35d 19' 18.9\"\nwith an uncertainty of 1.4 arcmin, (radius, sys+stat, 90% containment).\nThe partial coding was 57%.\n\nThe mask-weighted light curve shows a multi-peaked structure that\nstarts at ~T-15 s and peaks at ~T0. The burst emission lasted\nuntil the burst went out of the BAT FOV at T+287 s.\nUsing the available data, the lower limit of T90 is ~ 240 s.\n\nThe time-averaged spectrum from T-14.27 to T+266.26 sec is best fit by\na power law with an exponential cutoff.  This fit gives a photon\nindex 0.77 +- 0.49, and Epeak of 91.3 +- 48.2 keV (chi squared 50.53\nfor 56 d.o.f.).  For this model the total fluence in the 15-150 keV\nband is 4.3 +- 0.3 x 10^-6 erg/cm2 and the 1-sec peak flux measured\nfrom T+0.09 sec in the 15-150 keV band is 1.0 +- 0.2 ph/cm2/sec.\nA fit to a simple power law gives a photon index of 1.46 +- 0.11\n(chi squared 57.43 for 57 d.o.f.).  All the quoted errors are at\nthe 90% confidence level.\n\nThe results of the batgrbproduct analysis are available at\nhttp://gcn.gsfc.nasa.gov/notices_s/1033328/BA/",
  "circularId": 29537,
  "createdOn": 1613700109000,
  "email": "amy.y.lien@nasa.gov",
  "subject": "GRB 210218A: Swift-BAT refined analysis",
  "submitter": "Amy Lien at GSFC  <amy.y.lien@nasa.gov>",
  "eventId": "GRB 210218A"
}