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GCN Circular 26012

GRB 191016A: Swift-BAT refined analysis
2019-10-16T21:40:40Z (4 years ago)
Sibasish Laha at GSFC <>
S. D. Barthelmy (GSFC), J. R. Cummings (CPI),
J.D. Gropp (PSU), H. A. Krimm (NSF),
S. Laha (GSFC/UMBC), 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-240 to T+962 sec from the recent telemetry
 downlink, we report further analysis of BAT GRB 191016A (trigger #929744)
(Gropp et al., GCN Circ. 26008).  The BAT ground-calculated position is
RA, Dec = 30.268, 24.508 deg which is
   RA(J2000)  =  02h 01m 04.4s
   Dec(J2000) = +24d 30' 30.4"
with an uncertainty of 1.5 arcmin, (radius, sys+stat, 90% containment).
The partial coding was 64%.

The mask weighted light curve shows two overlapping pulses.
Overall structure starts at ~ T-40 s and lasts till ~ T+420 s.
The two peaks occur at ~ T-10 s and ~ T+35 s, respectively.
T90 (15-350 keV) is 219.70 +- 183.35 sec (estimated error including systematics).

The time-averaged spectrum from T-42.82 to T+422.61 sec is best fit by a simple
power-law model.  The power law index of the time-averaged spectrum is
1.55 +- 0.09.  The fluence in the 15-150 keV band is 6.5 +- 0.4 x 10^-06 erg/cm2.
The 1-sec peak photon flux measured from T-7.75 sec in the 15-150 keV band
is 1.5 +- 0.2 ph/cm2/sec.  All the quoted errors are at the 90% confidence

The results of the batgrbproduct analysis are available at
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