[vsnet-grb-info 23947] GRB 191019A: Swift-BAT refined analysis

[GCN Circulars]

TITLE:   GCN CIRCULAR
NUMBER:  26046
SUBJECT: GRB 191019A: Swift-BAT refined analysis
DATE:    19/10/20 16:54:32 GMT
FROM:    Amy Lien at GSFC  <amy.y.lien at nasa.gov>

H. A. Krimm (NSF), S. D. Barthelmy (GSFC),
J. R. Cummings (CPI), S. Laha (GSFC/UMBC),
A. Y. Lien (GSFC/UMBC), C. B. Markwardt (GSFC),
D. M. Palmer (LANL), T. Sakamoto (AGU),
K. K. Simpson (PSU), M. Stamatikos (OSU),
T. N. Ukwatta (LANL) (i.e. the Swift-BAT team):

Using the data set from T-239 to T+963 sec from the recent telemetry
downlink, we report further analysis of BAT GRB 191019A (trigger #930285)
(Simpson et al., GCN Circ. 26031).  The BAT ground-calculated position is
RA, Dec = 340.035, -17.340 deg which is
   RA(J2000)  =  22h 40m 08.3s
   Dec(J2000) = -17d 20' 23.9"
with an uncertainty of 1.0 arcmin, (radius, sys+stat, 90% containment).
The partial coding was 46%.

The mask-weighted light curve shows a complex structure with many
overlapping
pulses that starts at ~T0 and ends at ~T+90 s. The burst went out of the
BAT FOV at ~T+400 s. T90 (15-350 keV) is 64.35 +- 4.45 sec (estimated error
including systematics).

The time-averaged spectrum from T-0.83 to T+84.28 sec is best fit by a
simple
power-law model.  The power law index of the time-averaged spectrum is
2.25 +- 0.05.  The fluence in the 15-150 keV band is 1.0 +- 0.03 x 10^-5
erg/cm2.
The 1-sec peak photon flux measured from T-0.14 sec in the 15-150 keV band
is 5.7 +- 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/930285/BA/