[vsnet-grb-info 7178] GRB 081230, Swift-BAT refined analysis

[GCN Circulars]

TITLE:   GCN CIRCULAR
NUMBER:  8759
SUBJECT: GRB 081230, Swift-BAT refined analysis
DATE:    08/12/31 15:07:48 GMT
FROM:    Hans Krimm at NASA-GSFC  <hans.a.krimm at nasa.gov>

D. M. Palmer (LANL), S. D. Barthelmy (GSFC), W. H. Baumgartner (GSFC/UMBC),
J. R. Cummings (GSFC/UMBC), E. E. Fenimore (LANL), N. Gehrels (GSFC),
H. A. Krimm (GSFC/USRA), V. La Parola (INAF-IASFPA), C. B. Markwardt 
(GSFC/UMD),
K. McLean (GSFC/UMD), A. M. Parsons (GSFC), T. Sakamoto (GSFC/UMBC),
G. Sato (ISAS), M. Stamatikos (GSFC/ORAU), J. Tueller (GSFC),
T. N. Ukwatta (GWU) (i.e. the Swift-BAT team):

Using the data set from T-300 to T+1197 sec from the recent telemetry downlink,
we report further analysis of BAT GRB 081230 (trigger #338633)
(La Parola, et al., GCN Circ. 8753).  The BAT ground-calculated position is
RA, Dec = 37.330, -25.145 deg which is 
   RA(J2000)  =  02h 29m 19.2s 
   Dec(J2000) = -25d 08' 42.6" 
with an uncertainty of 1.4 arcmin, (radius, sys+stat, 90% containment).
The partial coding was 100%.
 
The mask-weighted light curve consists of a series of overlapping peaks ranging
from T+5 sec to T+70 sec, with the strongest emission at ~T+50 seconds.
T90 (15-350 keV) is 60.7 +- 13.8 sec (estimated error including systematics).
 
The time-averaged spectrum from T-14.4 to T+62.4 sec is best fit by a simple
power-law model.  The power law index of the time-averaged spectrum is
1.97 +- 0.16.  The fluence in the 15-150 keV band is 8.2 +- 0.8 x 10^-7 erg/cm2.
The 1-sec peak photon flux measured from T+46.63 sec in the 15-150 keV band
is 0.7 +- 0.1 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/338633/BA/