[vsnet-grb-info 17333] GRB 151215A: Swift-BAT refined analysis

[GCN Circulars]

TITLE:   GCN CIRCULAR
NUMBER:  18699
SUBJECT: GRB 151215A: Swift-BAT refined analysis
DATE:    15/12/15 22:29:18 GMT
FROM:    Tilan Ukwatta at LANL  <tilan.ukwatta at gmail.com>

J. R. Cummings (GSFC/UMBC), S. D. Barthelmy (GSFC),
N. Gehrels (GSFC), S. L. Gibson (U Leicester)
H. A. Krimm (GSFC/USRA), A. Y. Lien (GSFC/UMBC),
C. B. Markwardt (GSFC), D. M. Palmer (LANL),
T. Sakamoto (AGU), M. Stamatikos (OSU), T. N. Ukwatta (LANL)
(i.e. the Swift-BAT team):

Using the data set from T-240 to T+963 sec from the recent
telemetry downlink, we report further analysis of BAT
GRB 151215A (trigger #667392) (Gibson, et al., GCN
Circ. 18691). The BAT ground-calculated position is
RA, Dec = 93.622, 35.529 deg which is
   RA(J2000)  =  06h 14m 29.3s
   Dec(J2000) = +35d 31' 45.0"
with an uncertainty of 2.8 arcmin, (radius, sys+stat,
90% containment). The partial coding was 51%.

The mask-weighted light curve shows a multi-peak episode
starting ~T-15 sec, highest peak at ~T+0 sec, and the
episode ends around ~T+5 sec. T90 (15-350 keV)
is 17.8 +- 1.0 sec (estimated error including systematics).

The time-averaged spectrum from T-15.46 to T+3.13 sec is
best fit by a simple power-law model. The power law index
of the time-averaged spectrum is 1.99 +- 0.33. The fluence
in the 15-150 keV band is 3.1 +- 0.7 x 10^-07 erg/cm2.
The 1-sec peak photon flux measured from T-0.16 sec in
the 15-150 keV band is 1.6 +- 0.2 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/667392/BA/