TITLE:   GCN CIRCULAR
NUMBER:  33743
SUBJECT: GRB 230506C: Swift-BAT refined analysis
DATE:    23/05/07 18:42:20 GMT
FROM:    Amy Lien at GSFC <amy.y.lien@nasa.gov>

H. A. Krimm (NSF), S. D. Barthelmy (GSFC),
S. Laha (GSFC/UMBC), A. Y. Lien (U Tampa),
C. B. Markwardt (GSFC), D. M. Palmer (LANL),
T. Parsotan (GSFC/UMBC), T. Sakamoto (AGU),
M. Stamatikos (OSU), A. Tohuvavohu (U Toronto)
(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 230506C (trigger #1167288)
(Tohuvavohu et al., GCN Circ. 33731).  The BAT ground-calculated position is
RA, Dec = 134.371, 45.131 deg which is
   RA(J2000)  =  08h 57m 29.1s
   Dec(J2000) = +45d 07' 50.7"
with an uncertainty of 1.4 arcmin, (radius, sys+stat, 90% containment).
The partial coding was 46%.

The mask-weighted light curve shows a multi-peaked structure that starts
at ~T-9 s and ends at ~T+28 s. The main peak occurs at ~T+1 s.
T90 (15-350 keV) is 31.00 +- 6.32 sec (estimated error
including systematics).

The time-averaged spectrum from T-8.59 to T+28.41 sec is best fit by
a simple power-law model.  The power law index of the time-averaged
spectrum is 1.89 +- 0.17.  The fluence in the 15-150 keV band
is 1.7 +- 0.2 x 10^-6 erg/cm2. The 1-sec peak photon flux measured
from T+0.41 sec in the 15-150 keV band is 2.4 +- 0.5 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/1167288/BA/