GCN Circular 28223
Subject
GRB 200806A: Swift-BAT refined analysis
Date
2020-08-07T18:10:15Z (4 years ago)
From
Hans Krimm at NSF/NASA-GSFC <hkrimm@nsf.gov>
A. Y. Lien (GSFC/UMBC), E. Ambrosi (INAF-IASFPA), S. D. Barthelmy (GSFC),
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-60 to T+243 sec from the recent telemetry downlink,
we report further analysis of BAT GRB 200806A (trigger #987016)
(Ambrosi, et al., GCN Circ. 28211). The BAT ground-calculated position is
RA, Dec = 52.933, 37.076 deg which is
RA(J2000) = 03h 31m 43.9s
Dec(J2000) = +37d 04' 33.5"
with an uncertainty of 1.0 arcmin, (radius, sys+stat, 90% containment).
The partial coding was 57%.
The mask-weighted light curve shows a multi-peaked structure, with a sharp
rise close to T+0 sec. The emission peaked at T+22 sec and declined to
background by T+50 sec. T90 (15-350 keV) is 38.8 +- 1.1 sec (estimated error
including systematics).
The time-averaged spectrum from T-0.13 to T+61.22 sec is best fit by a power law
with an exponential cutoff. This fit gives a photon index 0.72 +- 0.12,
and Epeak of 148.1 +- 18.6 keV (chi squared 40.06 for 56 d.o.f.). For this
model the total fluence in the 15-150 keV band is 1.6 +- 0.02 x 10^-5 erg/cm2
and the 1-sec peak flux measured from T+22.24 sec in the 15-150 keV band is
14.1 +- 0.4 ph/cm2/sec. A fit to a simple power law gives a photon index
of 1.27 +- 0.03 (chi squared 111.98 for 57 d.o.f.). 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/987016/BA/