T. Sakamoto (AGU), S. D. Barthelmy (GSFC), J. R. Cummings (GSFC/UMBC),
N. Gehrels (GSFC), H. A. Krimm (GSFC/USRA), A. Y. Lien (GSFC/UMBC),
C. B. Markwardt (GSFC), D. M. Palmer (LANL), J. L. Racusin (NASA/GSFC),
M. Stamatikos (OSU), T. N. Ukwatta (LANL) (i.e. the Swift-BAT team):
Using the data set from T-239 to T+963 sec from the recent telemetry downlinks,
we report further analysis of BAT GRB 150925A (trigger #656604)
(Racusin, et al., GCN Circ. 18365). The BAT ground-calculated position is
RA, Dec = 227.538, -19.640 deg, which is
RA(J2000) = 15h 10m 09.0s
Dec(J2000) = -19d 38' 22.3"
with an uncertainty of 2.0 arcmin, (radius, sys+stat, 90% containment).
The partial coding was 56%.
The mask-weighted light curve show several overlapping peaks starting at ~T-0,
peaking at ~T+25 sec, and ending at ~T+180 sec. T90 (15-350 keV) is
121 +- 27 sec (estimated error including systematics).
The time-averaged spectrum from T+3.51 to T+149.61 sec is best fit by a simple
power-law model. The power law index of the time-averaged spectrum is
2.19 +- 0.20. The fluence in the 15-150 keV band is 1.4 +- 0.2 x 10^-6 erg/cm2.
The 1-sec peak photon flux measured from T+30.68 sec in the 15-150 keV band
is 0.6 +- 0.2 ph/cm2/sec. All the quoted errors are at the 90% confidence
The results of the batgrbproduct analysis are available at