[vsnet-grb-info 12275] GRB 120816A: Swift-BAT refined analysis

[GCN Circulars]

TITLE:   GCN CIRCULAR
NUMBER:  13659
SUBJECT: GRB 120816A: Swift-BAT refined analysis
DATE:    12/08/17 02:28:16 GMT
FROM:    Scott Barthelmy at NASA/GSFC  <scott at lheamail.gsfc.nasa.gov>

S. D. Barthelmy (GSFC), W. H. Baumgartner (GSFC/UMBC), J. R. Cummings (GSFC/UMBC),
E. E. Fenimore (LANL), N. Gehrels (GSFC), H. A. Krimm (GSFC/USRA),
C. B. Markwardt (GSFC), K. L. Page (U Leicester), D. M. Palmer (LANL),
T. Sakamoto (GSFC/UMBC), G. Sato (ISAS), M. Stamatikos (OSU),
J. Tueller (GSFC), T. N. Ukwatta (MSU)
(i.e. the Swift-BAT team):
 
Using the data set from T-60 to T+192 sec from the recent telemetry downlink,
we report further analysis of BAT GRB 120816A (trigger #531223)
(Page, et al., GCN Circ. 13654).  The BAT ground-calculated position is
RA, Dec = 282.133, -6.981 deg, which is 
   RA(J2000)  =  18h 48m 32.0s 
   Dec(J2000) = -06d 58' 51.6" 
with an uncertainty of 2.5 arcmin, (radius, sys+stat, 90% containment).
The partial coding was 9%.
 
The mask-weighted light curve shows a single peak starting at ~T+0 sec,
peaking at ~T+1 sec, and ending at ~T+8 sec.  T90 (15-350 keV) is
7.6 +- 3.1 sec (estimated error including systematics).
 
The time-averaged spectrum from T-1.97 to T+6.66 sec is best fit by a simple
power-law model.  The power law index of the time-averaged spectrum is
2.54 +- 0.40.  The fluence in the 15-150 keV band is 4.3 +- 1.0 x 10^-7 erg/cm2.
The 1-sec peak photon flux measured from T+0.82 sec in the 15-150 keV band
is 2.1 +- 0.5 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/531223/BA/