{
  "circularId": 43354,
  "bibcode": "2026GCN.43354....1M",
  "createdOn": 1767927604173,
  "submitter": "Tyler Parsotan  at NASA GSFC <tyler.parsotan@nasa.gov>",
  "body": "C. B. Markwardt (GSFC), S. D. Barthelmy (GSFC),\nS. B. Cenko (GSFC), R. Gupta (GSFC),\nH. A. Krimm (NSF), S. Laha (GSFC/UMBC),\nA. Y. Lien (U Tampa), M. J. Moss (GSFC),\nD. M. Palmer (LANL), T. Parsotan (GSFC),\nD. Sadaula (GSFC/UMBC), T. Sakamoto (AGU)\n(i.e. the Swift-BAT team):\n\nUsing the data set from T-239 to T+1066 sec from the recent telemetry downlink,\nwe report further analysis of BAT GRB 260101A (trigger #1429608)\n(Cenko, et al., GCN Circ. 43285).  The BAT ground-calculated position is\nRA, Dec = 86.442, 63.583 deg which is\n   RA(J2000)  =  05h 45m 46.2s\n   Dec(J2000) = +63d 34' 57.2\"\nwith an uncertainty of 1.1 arcmin, (radius, sys+stat, 90% containment).\nThe partial coding was 78%.\n\nThe mask-weighted light curve shows a complex light curve with many emission episodes. T90 (15-350 keV) is 48.00 +- 16.00 sec (estimated error including systematics).\n\nThe time-averaged spectrum from T-31.26 to T+64.74 sec is best fit by a power law\nwith an exponential cutoff.  This fit gives a photon index 1.28 +- 0.23,\nand Epeak of 109.2 +- 64.4 keV (chi squared 55.17 for 56 d.o.f.).  For this\nmodel the total fluence in the 15-150 keV band is 4.5 +- 0.2 x 10^-06 erg/cm2\nand the 1-sec peak flux measured from T+24.24 sec in the 15-150 keV band is\n4.6 +- 0.3 ph/cm2/sec.  A fit to a simple power law gives a photon index\nof 1.62 +- 0.06 (chi squared 62.07 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 https://swift.gsfc.nasa.gov/results/batgrbcat/BAT_refined_circular/1429608\n\n\n\n",
  "eventId": "GRB 260101A",
  "submittedHow": "email",
  "subject": "GRB 260101A: Swift-BAT refined analysis"
}