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GCN Circular 16218

Subject

GRB 140506A: Swift-BAT refined analysis

Date

2014-05-07T11:50:34Z (11 years ago)

From

Scott Barthelmy at NASA/GSFC <scott@lheamail.gsfc.nasa.gov>

C. B. Markwardt (GSFC), S. D. Barthelmy (GSFC), W. H. Baumgartner (GSFC/UMBC),
J. R. Cummings (GSFC/UMBC), N. Gehrels (GSFC), B.P. Gompertz (U Leicester),
H. A. Krimm (GSFC/USRA), A. Y. Lien (NASA/UMBC), D. M. Palmer (LANL),
T. Sakamoto (AGU), M. Stamatikos (OSU), J. Tueller (GSFC), T. N. Ukwatta (MSU)
(i.e. the Swift-BAT team):
 
Using the data set from T-240 to T+962 sec from recent telemetry downlinks,
we report further analysis of BAT GRB 140506A (trigger #598284)
(Gompertz, et al., GCN Circ. 16214Not found
 
 
).  The BAT ground-calculated position is
RA, Dec = 276.806, -55.556 deg, which is 
   RA(J2000)  =  18h 27m 13.5s 
   Dec(J2000) = -55d 33' 20.2" 
with an uncertainty of 1.6 arcmin, (radius, sys+stat, 90% containment).
The partial coding was 11%.
 
The mask-weighted light curve a bright initial pulse strting at ~T-5 sec,
peaking at ~T+0.2 sec, and returning to baseline at ~T+5 sec. Then there were
two weaker peaks at ~T+60 sec and at ~T+110 sec.  T90 (15-350 keV) is
111.1 +- 9.6 sec (estimated error including systematics).
 
The time-averaged spectrum from T-0.20 to T+120.18 sec is best fit by a simple
power-law model.  The power law index of the time-averaged spectrum is
1.68 +- 0.16.  The fluence in the 15-150 keV band is 2.8 +- 0.3 x 10^-6 erg/cm2.
The 1-sec peak photon flux measured from T+0.00 sec in the 15-150 keV band
is 10.9 +- 0.9 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/598284/BA/