TITLE: GCN CIRCULAR NUMBER: 40609 SUBJECT: GRB 250530C: Swift-BAT refined analysis DATE: 25/06/02 19:11:33 GMT FROM: Mike Moss at NASA GSFC <mikejmoss3@gmail.com> D. Sadaula (GSFC/UMBC), S. D. Barthelmy (GSFC), R. Caputo (NASA/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), T. Sakamoto (AGU) (i.e. the Swift-BAT team): Using the data set from T-240 to T+885 sec from the recent telemetry downlink, we report further analysis of BAT GRB 250530C (trigger #1319125) (Caputo, et al., GCN Circ. 40585). The BAT ground-calculated position is RA, Dec = 55.146, -22.457 deg which is RA(J2000) = 03h 40m 35.1s Dec(J2000) = -22d 27' 26.1" with an uncertainty of 1.8 arcmin, (radius, sys+stat, 90% containment). The partial coding was 96%. The mask-weighted light curve displays a complex structure with multiple dim pulses. The T90 (15-350 keV) is 42.86 +- 6.04 sec (estimated error including systematics). The time-averaged spectrum from T-29.77 to T+21.26 sec is best fit by a simple power-law model. The power law index of the time-averaged spectrum is 1.32 +- 0.17. The fluence in the 15-150 keV band is 8.5 +- 0.9 x 10^-07 erg/cm2. The 1-sec peak photon flux measured from T-0.28 sec in the 15-150 keV band is 0.8 +- 0.2 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/1319125 View this GCN Circular online at https://gcn.nasa.gov/circulars/40609. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0LW...