TITLE:   GCN CIRCULAR
NUMBER:  22921
SUBJECT: GRB 180706A: Swift-BAT refined analysis
DATE:    18/07/06 18:11:57 GMT
FROM:    Amy Lien at GSFC  <amy.y.lien@nasa.gov>

T. Sakamoto (AGU), S. D. Barthelmy (GSFC),
J. R. Cummings (CPI), H. A. Krimm (NSF/USRA),
A. Y. Lien (GSFC/UMBC), C. B. Markwardt (GSFC),
D. M. Palmer (LANL), 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 180706A (trigger #846395)
(Stamatikos et al., GCN Circ. 22909).  The BAT ground-calculated position is
RA, Dec = 181.687, 66.044 deg which is
  RA(J2000)  =  12h 06m 45.0s
  Dec(J2000) = +66d 02' 40.1"
with an uncertainty of 1.1 arcmin, (radius, sys+stat, 90% containment).
The partial coding was 86%.

The mask-weighted light curve shows a double-peaked structure that starts
at ~T-20 s and ends at ~T+50 s. The smaller peak occurs at ~T+2 s, and
the larger peak happens at ~T+28 s. T90 (15-350 keV) is 42.7 +- 8.7 sec
(estimated error including systematics).

The time-averaged spectrum from T-18.77 to T+50.99 sec is best fit by a simple
power-law model.  The power law index of the time-averaged spectrum is
1.90 +- 0.08.  The fluence in the 15-150 keV band is 2.4 +- 0.1 x 10^-6 erg/cm2.
The 1-sec peak photon flux measured from T+27.82 sec in the 15-150 keV band
is 3.2 +- 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/846395/BA/