[vsnet-grb-info 2452] GRB 051117A: Refined analysis of the Swift-BAT burst

[GCN Circulars]

TITLE:   GCN GRB OBSERVATION REPORT
NUMBER:  4289
SUBJECT: GRB 051117A:  Refined analysis of the Swift-BAT burst
DATE:    05/11/17 21:52:20 GMT
FROM:    Scott Barthelmy at NASA/GSFC  <Scott at lheamail.gsfc.nasa.gov>

D. Palmer (LANL), L. Barbier (GSFC), S. Barthelmy (GSFC),
L. Cominsky (Sonoma State U.), J. Cannizzo (GSFC-UMBC),
J. Cummings (GSFC/NRC), E. Fenimore (LANL), N. Gehrels (GSFC),
D. Hullinger (GSFC/UMD), H. Krimm (GSFC/USRA), C. Markwardt (GSFC/UMD), 
A. Parsons (GSFC), T. Sakamoto (GSFC/NRC), G. Sato (ISAS),
J. Tueller (GSFC)
on behalf of the Swift-BAT team:

Using the full data set from the recent telemetry downlink,
we report further analysis of Swift-BAT GRB 051117A (trigger #164268)
(Band, et al., GCN 4280).  The ground-analysis position is
RA,Dec 228.399,+30.870 {15h 13m 35.7s,+30d 51' 10.3"} (J2000)
with an uncertainty of 1.0 arcmin (radius, 90%, stat+sys).
T90 is at least 140 +- 10 sec.  The partial coding fraction is 72%.
The lightcurve has a long FRED-like peak at T-15 sec
lasting out to at least T+190 sec.  There is a hint of emission 
peaks at T+225 and T+350 (each ~30 sec in duration).
Fitting a simple power law over the interval from T-29 to T+157 sec,
the photon index is 1.83 +/- 0.07 with a fluence of at least
4.6 +/- 0.16 X 10^-6 erg/cm^2.  The peak flux in a 1-sec wide window
starting at T+2.47 sec is 0.93 +/- 0.17 ph/cm^2/sec.  All values are
in the 15-150 keV band at the 90% confidence level.