GCN Circular 12424

W. H. Baumgartner (GSFC/UMBC),S. D. Barthelmy (GSFC), J. R. Cummings (GSFC/UMBC),
E. E. Fenimore (LANL), N. Gehrels (GSFC), H. A. Krimm (GSFC/USRA),
C. B. Markwardt (GSFC), D. M. Palmer (LANL), T. Sakamoto (GSFC/UMBC),
C. J. Saxton (UCL-MSSL), M. Stamatikos (OSU), J. Tueller (GSFC),
T. N. Ukwatta (MSU) (i.e. the Swift-BAT team):

Using the data set from T-240 to T+302 sec from the recent telemetry downlink,
we report further analysis of BAT GRB 111008A (trigger #505054)
(Saxton, et al., GCN Circ. 12423
Not found
 
 
).  The BAT ground-calculated position is
RA, Dec = 60.439, -32.708 deg which is
    RA(J2000)  =  04h 01m 45.3s
    Dec(J2000) = -32d 42' 29.3"
with an uncertainty of 1.2 arcmin, (radius, sys+stat, 90% containment).
The partial coding was 9%.

The mask-tagged light curve shows three clusters of peaks, each containing at least
two subpeaks, and with returns to the baseline between clusters.  Each cluster
is softer and weaker than the one preceding it. The first cluster runs from
T-10 sec to T+10 sec, the second runs from T+28 sec to T+35 sec, and the third
from T+58 to T+65 sec.  We note that there is a gap in the telemetry from T+180
to T+240 sec, but there is no indication of any emission between the last peak
and the gap or after the gap. T90 (15-350 keV) is 63.46 +- 2.19 sec (estimated
error including systematics).

The time-averaged spectrum from T-2.64 to T+68.80 sec is best fit by a simple
power-law model.  The power law index of the time-averaged spectrum is
1.86 +- 0.09.  The fluence in the 15-150 keV band is 5.3 +- 0.3 x 10^-6 erg/cm2.
The 1-sec peak photon flux measured from T+0.04 sec in the 15-150 keV band
is 6.4 +- 0.7 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/505054/BA/