TITLE: GCN CIRCULAR NUMBER: 36072 SUBJECT: GRB 240411B: Swift-BAT refined analysis DATE: 24/04/12 17:35:46 GMT FROM: Mike Moss at NASA GSFC <mikejmoss3@gmail.com> A. Y. Lien (U Tampa), S. D. Barthelmy (GSFC), H. A. Krimm (NSF), S. Laha (GSFC/UMBC), C. B. Markwardt (GSFC), M. J. Moss (GSFC), D. M. Palmer (LANL), T. Parsotan (GSFC), 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 240411B (trigger #1221183) (Parsotan, et al., GCN Circ. 36063). The BAT ground-calculated position is RA, Dec = 231.562, -2.172 deg which is RA(J2000) = 15h 26m 14.8s Dec(J2000) = -02d 10' 20.9" with an uncertainty of 3.3 arcmin, (radius, sys+stat, 90% containment). The partial coding was 53%. The mask-weighted light curve shows two spikes separated by an interval of ~15 seconds. The estimated T90 (15-350 keV) is 33.26 +- 1.49 sec (estimated error including systematics). The time-averaged spectrum from T-0.37 to T+33.92 sec is best fit by a simple power-law model. The power law index of the time-averaged spectrum is 1.69 +- 0.41. The fluence in the 15-150 keV band is 4.9 +- 1.2 x 10^-07 erg/cm2. The 1-sec peak photon flux measured from T+32.87 sec in the 15-150 keV band is 0.9 +- 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/1221183 View this GCN Circular online at https://gcn.nasa.gov/circulars/36072. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0LW...