[vsnet-grb-info 3042] GRB 060313: Further analysis of the Swift-BAT bright short hard burst

[GCN Circulars]

TITLE:   GCN GRB OBSERVATION REPORT
NUMBER:  4879
SUBJECT: GRB 060313:  Further analysis of the Swift-BAT bright short hard burst
DATE:    06/03/14 00:11:51 GMT
FROM:    Scott Barthelmy at NASA/GSFC  <Scott at lheamail.gsfc.nasa.gov>

S. Barthelmy (GSFC), J. Cummings (GSFC/NRC), N. Gehrels (GSFC),
H. Krimm (GSFC/USRA), J. Norris (GSFC), T. Sakamoto (GSFC/NRC),
D. Palmer (LANL
on behalf of the Swift-BAT team:

Using the data set from T-300 to T+300 sec from additional telemetry
downlinks, we report further analysis of BAT GRB 060313 (trigger #201487)
(Pagani, et al., GCN 4867; Markwardt, et al., 4873).  This short burst
does not show any sign of extended emission in the T+1 to T+300 sec range
at an upper limit of 0.001 cnt/detector/sec.  This corresponds to a
flux ratio upper limit between the initial peak and the peak of any
potential extended emission of 2000.  We reference SHBs 050724 and 051227
which had ratios of 46 and ~10, respectively.

The lag analysis shows this burst to be cleanly in the short hard burst class
(Norris and Bonnell, 2006, ApJ, accepted; see, Figure 3).
Specifically, the measured lags are:
 50-100 keV to 15-25 keV:  0.8 ms +- 0.6 ms
100-350 keV to 25-50 keV:  0.3 ms +- 0.7 ms

We further note that the lightcurve has multiple structures.  There are
at least 20 statistically significant peaks with FWHM in the 5-15 msec range.
There is no perdiodic structure in the lightcurve for at least
the first 100 sec.