TITLE:   GCN CIRCULAR
NUMBER:  23294
SUBJECT: GRB 181002A: Swift-BAT refined analysis 
DATE:    18/10/02 22:58:09 GMT
FROM:    Amy Lien at GSFC  <amy.y.lien@nasa.gov>

J. R. Cummings (CPI), S. D. Barthelmy (GSFC),
J.D. Gropp (PSU), H. A. Krimm (NSF/USRA),
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 181002A (trigger #865036)
(Gropp et al., GCN Circ. 23290).  The BAT ground-calculated position is
RA, Dec = 64.739, 15.248 deg which is
  RA(J2000)  =  04h 18m 57.4s
  Dec(J2000) = +15d 14' 51.6"
with an uncertainty of 1.8 arcmin, (radius, sys+stat, 90% containment).
The partial coding was 70%.

The mask-weighted light curve shows a weak pulse that starts at ~T-30 s and
ends at ~T+45 s. T90 (15-350 keV) is 63.4 +- 12.4 sec (estimated error
including systematics).

The time-averaged spectrum from T-28.38 to T+43.62 sec is best fit by a simple
power-law model.  The power law index of the time-averaged spectrum is
2.15 +- 0.23.  The fluence in the 15-150 keV band is 8.8 +- 1.3 x 10^-7 erg/cm2.
The 1-sec peak photon flux measured from T+11.39 sec in the 15-150 keV band
is 0.6 +- 0.2 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/865036/BA/