[vsnet-grb-info 17892] GRB 160424A: Swift-BAT refined analysis

[GCN Circulars]

TITLE:   GCN CIRCULAR
NUMBER:  19338
SUBJECT: GRB 160424A: Swift-BAT refined analysis
DATE:    16/04/24 20:17:34 GMT
FROM:    Scott Barthelmy at NASA/GSFC  <scott at lheamail.gsfc.nasa.gov>

H. A. Krimm (GSFC/USRA), S. D. Barthelmy (GSFC), J. R. Cummings (GSFC/UMBC),
N. Gehrels (GSFC), 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-61 to T+243 sec from the recent telemetry downlinks,
we report further analysis of BAT GRB 160424A (trigger #683906)
(Lien, et al., GCN Circ. 19335).  The BAT ground-calculated position is
RA, Dec = 319.482, -60.408 deg, which is 
   RA(J2000)  =  21h 17m 55.7s 
   Dec(J2000) = -60d 24' 29.8" 
with an uncertainty of 1.2 arcmin, (radius, sys+stat, 90% containment).
The partial coding was 33%.
 
The mask-weighted light curve shows a FRED-like peak starting at ~T-0.5 sec,
peaking at ~T+0.4 sec, and ending at ~T+10 sec.  T90 (15-350 keV) is
6.3 +- 1.0 sec (estimated error including systematics).
 
The time-averaged spectrum from T-1.51 to T+6.63 sec is best fit by a simple
power-law model.  The power law index of the time-averaged spectrum is
1.40 +- 0.10.  The fluence in the 15-150 keV band is 1.2 +- 0.1 x 10^-6 erg/cm2.
The 1-sec peak photon flux measured from T+0.06 sec in the 15-150 keV band
is 5.1 +- 0.4 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/683906/BA/