TITLE: GCN CIRCULAR NUMBER: 43563 SUBJECT: GRB 260127A: Swift-BAT refined analysis DATE: 26/01/29 21:16:56 GMT FROM: D. R. Sadaula at NASA GSFC <dev.r.sadaula@nasa.gov> T. Parsotan (GSFC), S. D. Barthelmy (GSFC), R. Gupta (GSFC), H. A. Krimm (NSF), S. Laha (GSFC/UMBC), A. Y. Lien (U Tampa), C. B. Markwardt (GSFC), M. J. Moss (GSFC), D. M. Palmer (LANL), T. Parsotan (GSFC), D. Sadaula (GSFC/UMBC), T. Sakamoto (AGU) (i.e. the Swift-BAT team) Using the data set from T-239 to T+963 sec from the recent telemetry downlink, we report further analysis of BAT GRB 260127A (trigger #1444088) (Kilingler et al., GCN Circ. 43529). The BAT ground-calculated position is RA, Dec = 231.879, 6.758 deg which is RA(J2000) = 15h 27m 30.9s Dec(J2000) = +06d 45' 28.4" with an uncertainty of 1.7 arcmin, (radius, sys+stat, 90% containment). The partial coding was 40%. The classic pulse has a single peak that started around T+20 sec and has a structure before it at ~T+5 sec. The duration of the burst is ~100 sec. T90 (15-350 keV) is 104.06 +- 19.41 sec (estimated error including systematics). The time-averaged spectrum using multiple GTIs from T-2.68 to T+7.62, T+9.00 to T+84.43 sec, and T+86.00 to T+117.04 sec is best fit by a simple power-law model. The power law index of the time-averaged spectrum is 1.76 +- 0.15. The fluence in the 15-150 keV band is 2.3 +- 0.2 x 10^-06 erg/cm2. The 1-sec peak photon flux measured from T+33.36 sec in the 15-150 keV band is 2.1 +- 0.3 ph/cm2/sec. All the quoted errors are at the 90% confidence level. The results of the batgrbproduct analysis are available at https://swift.gsfc.nasa.gov/results/batgrbcat/BAT_refined_circular/1444088 View this GCN Circular online at https://gcn.nasa.gov/circulars/43563. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0LW...