[vsnet-grb-info 17069] GRB 151001B: Swift-BAT refined analysis

[GCN Circulars]

TITLE:   GCN CIRCULAR
NUMBER:  18382
SUBJECT: GRB 151001B: Swift-BAT refined analysis
DATE:    15/10/02 13:09:51 GMT
FROM:    Scott Barthelmy at NASA/GSFC  <scott at lheamail.gsfc.nasa.gov>

T. N. Ukwatta (LANL), 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), T. Sakamoto (AGU),
M. Stamatikos (OSU),
(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 151001B (trigger #657321)
(Krimm, et al., GCN Circ. 18374).  The BAT ground-calculated position is
RA, Dec = 336.974, 64.637 deg, which is 
   RA(J2000)  =  22h 27m 53.7s 
   Dec(J2000) = +64d 38' 13.5" 
with an uncertainty of 2.1 arcmin, (radius, sys+stat, 90% containment).
The partial coding was 28%.
 
The mask-weighted light curves shows several overlapping peaks starting
at ~T-40 sec, peaking at ~T+50 sec, and ending at ~T+150 sec.
T90 (15-350 keV) is 109 +- 17 sec (estimated error including systematics).
 
The time-averaged spectrum from T-23.3 to T+97 sec is best fit by a simple
power-law model.  The power law index of the time-averaged spectrum is
2.12 +- 0.27.  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+47.47 sec in the 15-150 keV band
is 0.5 +- 0.3 ph/cm2/sec.  All the quoted errors are at the 90% confidence
level. 
 
The results of the batgrbproduct analysis are available at
http://gcn.gsfc.nasa.gov/notices_s/657321/BA/