TITLE:   GCN CIRCULAR
NUMBER:  20151
SUBJECT: GRB 161108A, Swift-BAT refined analysis
DATE:    16/11/08 22:14:28 GMT
FROM:    Amy Lien at GSFC  <amy.y.lien@nasa.gov>

D. M. Palmer (LANL), S. D. Barthelmy (GSFC),
A. P. Beardmore (U Leicester), J. R. Cummings (GSFC/UMBC),
N. Gehrels (GSFC), H. A. Krimm (GSFC/USRA),
A. Y. Lien (GSFC/UMBC), C. B. Markwardt (GSFC),
T. Sakamoto (AGU), 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 161108A (trigger #721234)
(Beardmore, et al., GCN Circ. 20145).  The BAT ground-calculated position is
RA, Dec = 180.776, 24.905 deg which is
  RA(J2000)  =  12h 03m 06.1s
  Dec(J2000) = +24d 54' 19.4"
with an uncertainty of 1.9 arcmin, (radius, sys+stat, 90% containment).
The partial coding was 95%.

The mask-weighted light curve shows a multi-peaked structure that starts
at ~ T-5 s and ends at ~ T+ 130 s. The main peak occurs at ~T0.
T90 (15-350 keV) is 105.1 +- 11.9 sec (estimated error including systematics).

The time-averaged spectrum from T-1.9 to T+126.8 sec is best fit by a simple
power-law model.  The power law index of the time-averaged spectrum is
1.85 +- 0.17.  The fluence in the 15-150 keV band is 1.1 +- 0.1 x 10^-6 erg/cm2.
The 1-sec peak photon flux measured from T-1.80 sec in the 15-150 keV band
is 0.6 +- 0.1 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/721234/BA/