TITLE: GCN CIRCULAR NUMBER: 35473 SUBJECT: GRB 240101A: Swift-BAT refined analysis DATE: 24/01/03 14:06:48 GMT FROM: Hans Krimm at NSF/NASA-GSFC <hkrimm@nsf.gov> A. Y. Lien (U Tampa), S. D. Barthelmy (GSFC), S. B. Cenko (GSFC), H. A. Krimm (NSF), S. Laha (GSFC/UMBC), C. B. Markwardt (GSFC), M. J. Moss (GSFC), D. M. Palmer (LANL), T. Parsotan (GSFC/UMBC), T. Sakamoto (AGU), M. Stamatikos (OSU) (i.e. the Swift-BAT team): Using the data set from T-10 to T+242 sec from the recent telemetry downlink, we report further analysis of BAT GRB 240101A (trigger #1205708) (Cenko, et al., GCN Circ. 35448). The trigger time, which was unavailable in the first circular was 2024-01-01 at 14:20:17.331 UTC. The BAT ground-calculated position is RA, Dec = 10.289, 8.540 deg which is RA(J2000) = 00h 41m 09.5s Dec(J2000) = +08d 32' 25.3" with an uncertainty of 3.8 arcmin, (radius, sys+stat, 90% containment). The partial coding was 66%. The mask-weighted light curve shows a weak, complex structure lasting from About T-5 to T+10 seconds. T90 (15-350 keV) is 15.8 +- 6.1 sec (estimated error including systematics). The time-averaged spectrum from T-1.94 to T+20.28 sec is best fit by a simple power-law model. The power law index of the time-averaged spectrum is 2.03 +- 0.34. The fluence in the 15-150 keV band is 3.3 +- 0.7 x 10^-7 erg/cm2. The 1-sec peak photon flux measured from T+2.11 sec in the 15-150 keV band is 0.9 +- 0.2 ph/cm2/sec. All the quoted errors are at the 90% confidence level. The results of the batgrbproduct analysis are available at http://gcn.gsfc.nasa.gov/notices_s/1205708/BA/ View this GCN Circular online at https://gcn.nasa.gov/circulars/35473. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0LW...