[vsnet-grb-info 20297] GRB 180205A: Swift-BAT refined analysis

[GCN Circulars]

TITLE:   GCN CIRCULAR
NUMBER:  22393
SUBJECT: GRB 180205A: Swift-BAT refined analysis
DATE:    18/02/06 02:57:19 GMT
FROM:    Amy Lien at GSFC  <amy.y.lien at nasa.gov>

H. A. Krimm (NSF/USRA), S. D. Barthelmy (GSFC),
J. R. Cummings (CPI), P. A. Evans (U Leicester),
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+700 sec from the recent telemetry downlink,
we report further analysis of BAT GRB 180205A (trigger #808625)
(Evans et al., GCN Circ. 22381).  The BAT ground-calculated position is
RA, Dec = 126.819, 11.536 deg which is
  RA(J2000)  =  08h 27m 16.5s
  Dec(J2000) = +11d 32' 11.1"
with an uncertainty of 1.1 arcmin, (radius, sys+stat, 90% containment).
The partial coding was 50%.

The mask-weighted light curve shows a multi-peaked structure that starts
at ~T-7 s and ends at ~T+11 s. The two major peaks occur at ~T-5 s
and ~T0 s, respectively. T90 (15-350 keV) is 15.5 +- 3.1 sec (estimated
error including systematics).

The time-averaged spectrum from T-7.04 to T+10.87 sec is best fit by a simple
power-law model.  The power law index of the time-averaged spectrum is
2.04 +- 0.13.  The fluence in the 15-150 keV band is 1.0 +- 0.1 x 10^-6 erg/cm2.
The 1-sec peak photon flux measured from T-0.20 sec in the 15-150 keV band
is 3.4 +- 0.3 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/808625/BA/