TITLE:   GCN CIRCULAR
NUMBER:  27353
SUBJECT: GRB 200306C: Swift-BAT refined analysis
DATE:    20/03/09 06:03:42 GMT
FROM:    Amy Lien at GSFC  <amy.y.lien@nasa.gov>

M. Stamatikos (OSU), S. D. Barthelmy (GSFC),
J. R. Cummings (CPI), J.D. Gropp (PSU),
H. A. Krimm (NSF), S. Laha (GSFC/UMBC),
A. Y. Lien (GSFC/UMBC), C. B. Markwardt (GSFC),
D. M. Palmer (LANL), T. Sakamoto (AGU),
T. N. Ukwatta (LANL) (i.e. the Swift-BAT team):

Using the data set from T-240 to T+1065 sec from the recent telemetry
downlink,
we report further analysis of BAT GRB 200306C (trigger #960102)
(Gropp et al., GCN Circ. 27326).  The BAT ground-calculated position is
RA, Dec = 198.577, 11.263 deg which is
   RA(J2000)  =  13h 14m 18.6s
   Dec(J2000) = +11d 15' 47.7"
with an uncertainty of 1.3 arcmin, (radius, sys+stat, 90% containment).
The partial coding was 42%.

The mask-weighted light curve shows several overlapping pulses
that start at ~T-12 s and end at ~T+50 s. T90 (15-350 keV)
is 53.5 +- 12.8 sec (estimated error including systematics).

The time-averaged spectrum from T-12.33 to T+50.70 sec is best fit by a
simple
power-law model.  The power law index of the time-averaged spectrum is
0.83 +- 0.12.  The fluence in the 15-150 keV band is 2.8 +- 0.2 x 10^-6
erg/cm2.
The 1-sec peak photon flux measured from T+3.45 sec in the 15-150 keV band
is 1.3 +- 0.3 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/960102/BA/