[vsnet-grb-info 18430] GRB 160827A: Swift-BAT refined analysis

[GCN Circulars]

TITLE:   GCN CIRCULAR
NUMBER:  19878
SUBJECT: GRB 160827A: Swift-BAT refined analysis
DATE:    16/08/27 22:23:49 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), K. L. Page (U Leicester), D. M. Palmer (LANL),
T. Sakamoto (AGU), M. Stamatikos (OSU),
(i.e. the Swift-BAT team):
 
Using the data set from T-60 to T+243 sec from the recent telemetry downlink,
we report further analysis of BAT GRB 160827A (trigger #710050)
(Page, et al., GCN Circ. 19876).  The BAT ground-calculated position is
RA, Dec = 179.274, -29.178 deg, which is 
   RA(J2000)  =  11h 57m 05.8s 
   Dec(J2000) = -29d 10' 40.9" 
with an uncertainty of 2.4 arcmin, (radius, sys+stat, 90% containment).
The partial coding was 48%.
 
The mask-weighted light curve shows a few olverlapping peaks starting
at ~T-5 sec, peaking at ~T+3 sec, and ending at ~T+13 sec.
T90 (15-350 keV) is 13.3 +- 2.2 sec (estimated error including systematics).
 
The time-averaged spectrum from T-5.81 to T+8.78 sec is best fit by a simple
power-law model.  The power law index of the time-averaged spectrum is
1.95 +- 0.25.  The fluence in the 15-150 keV band is 4.0 +- 0.7 x 10^-7 erg/cm2.
The 1-sec peak photon flux measured from T+2.49 sec in the 15-150 keV band
is 0.7 +- 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/710050/BA/