TITLE: GCN CIRCULAR NUMBER: 35472 SUBJECT: GRB 240101B: Swift-BAT refined analysis DATE: 24/01/03 14:03:29 GMT FROM: Hans Krimm at NSF/NASA-GSFC <hkrimm@nsf.gov> C. B. Markwardt (GSFC), S. D. Barthelmy (GSFC), S. B. Cenko (GSFC), H. A. Krimm (NSF), S. Laha (GSFC/UMBC), A. Y. Lien (U Tampa), 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-60 to T+243 sec from the recent telemetry downlink, we report further analysis of BAT GRB 240101B (trigger #1205744) (Cenko, et al., GCN Circ. 35449). The BAT ground-calculated position is RA, Dec = 352.147, 51.646 deg which is RA(J2000) = 23h 28m 35.3s Dec(J2000) = +51d 38' 46.9" with an uncertainty of 3.3 arcmin, (radius, sys+stat, 90% containment). The partial coding was 100%. The mask-weighted light curve shows a single peak from approximately T+0 To T+18 seconds. There is a possible precursor at T-50 sec. T90 (15-350 keV) is 43.1 +- 12.6 sec (estimated error including systematics). The time-averaged spectrum from T+2.18 to T+48.32 sec is best fit by a simple power-law model. The power law index of the time-averaged spectrum is 1.70 +- 0.26. The fluence in the 15-150 keV band is 4.6 +- 0.8 x 10^-7 erg/cm2. The 1-sec peak photon flux measured from T+10.28 sec in the 15-150 keV band is 0.5 +- 0.1 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/1205744/BA/ View this GCN Circular online at https://gcn.nasa.gov/circulars/35472. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0LW...