[vsnet-grb-info 4749] GRB 070610, Swift-BAT refined analysis

[GCN Circulars]

TITLE:   GCN CIRCULAR
NUMBER:  6491
SUBJECT: GRB 070610, Swift-BAT refined analysis
DATE:    07/06/11 00:01:17 GMT
FROM:    Scott Barthelmy at NASA/GSFC  <scott at lheamail.gsfc.nasa.gov>

J. Tueller (GSFC), L. Barbier (GSFC), S. D. Barthelmy (GSFC),
J. Cummings (GSFC/UMBC), E. Fenimore (LANL), N. Gehrels (GSFC),
H. Krimm (GSFC/USRA), C. Markwardt (GSFC/UMD), C. Pagani (PSU),
D. Palmer (LANL), A. Parsons (GSFC), T. Sakamoto (GSFC/ORAU),
G. Sato (GSFC/ISAS), M. Stamatikos (GSFC/ORAU), T. Ukwatta (GWU)
(i.e. the Swift-BAT team):
 
Using the data set from T-239 to T+427 sec from the recent telemetry downlink,
we report further analysis of BAT GRB 070610 (trigger #281993)
(Pagani, et al., GCN Circ. 6489).  The BAT ground-calculated position is
RA, Dec = 298.805, 26.256 deg  which is 
   RA(J2000)  = 19h 55m 13.1s 
   Dec(J2000) = 26d 15' 20" 
with an uncertainty of 1.8 arcmin, (radius, sys+stat, 90% containment).
The partial coding was 52%.
 
The mask-weighted light curve shows a single peak starting at ~T-2 sec
and ending at ~T+6 sec.  T90 (15-350 keV) is 4.6 +- 0.4 sec
(estimated error including systematics).
 
The time-averaged spectrum from T-0.8 to T+4.4 sec is best fit by a simple
power-law model.  The power law index of the time-averaged spectrum is
1.76 +- 0.25.  The fluence in the 15-150 keV band is 2.4 +- 0.4 x 10^-7 erg/cm2.
The 1-sec peak photon flux measured from T+1.76 sec in the 15-150 keV band
is 0.9 +- 0.2 ph/cm2/sec.  All the quoted errors are at the 90% confidence
level.