GCN Circular 42186
Subject
GRB 251007A: Swift-BAT refined analysis
Event
Date
2025-10-10T14:08:25Z (2 days ago)
From
Takanori Sakamoto at AGU <tsakamoto@phys.aoyama.ac.jp>
Via
Web form
S. Laha (GSFC/UMBC), E. Ambrosi (INAF-IASFPA), 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-240 to T+303 sec from the recent telemetry downlink,
we report further analysis of BAT GRB 251007A (trigger #1402466)
(Ambrosi, et al., GCN Circ. 42146). The BAT ground-calculated position is
RA, Dec = 128.162, 21.810 deg which is
RA(J2000) = 08h 32m 38.8s
Dec(J2000) = +21d 48' 36.6"
with an uncertainty of 1.5 arcmin, (radius, sys+stat, 90% containment).
The partial coding was 85%.
The mask-weighted light curve shows a complex structure starting at ~T-1 sec,
peaking at T+56 sec, and decaying to background at T+110 sec.
T90 (15-350 keV) is 64.19 +- 5.17 sec (estimated error including systematics).
The time-averaged spectrum from T-0.04 to T+103.43 sec is best fit by a simple
power-law model. The power law index of the time-averaged spectrum is
1.32 +- 0.03. The fluence in the 15-150 keV band is 1.04 +- 0.02 x
10^-5 erg/cm2. The 1-sec peak photon flux measured from T+56.14 sec
in the 15-150 keV band is 9.5 +- 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/1402466