[vsnet-grb-info 4356] GRB 070224, Swift-BAT refined analysis

[GCN Circulars]

TITLE:   GCN CIRCULAR
NUMBER:  6141
SUBJECT: GRB 070224, Swift-BAT refined analysis
DATE:    07/02/25 00:34:25 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), D. Palmer (LANL),
A. Parsons (GSFC), J. L. Racusin (PSU), T. Sakamoto (GSFC/ORAU),
G. Sato (GSFC/ISAS), M. Stamatikos (GSFC/ORAU)
on behalf of the Swift-BAT team:
 
Using the data set from T-239 to T+482 sec from the recent telemetry
downlink, we report further analysis of BAT GRB 070224 (trigger #261880)
(Racusin, et al., GCN Circ. 6137).  The BAT ground-calculated position
is RA, Dec = 178.987, -13.356 deg which is 
   RA(J2000)  =  11h 55m 57.0s 
   Dec(J2000) = -13d 21' 20.1" 
with an uncertainty of 2.0 arcmin, (radius, sys+stat, 90% containment).
The partial coding was 100%.
 
The mask-weighted lightcurve shows two overlapping peaks starting at ~T-20 sec
and decaying back to background at ~T+50 sec.  T90 (15-350 keV) is 34 +- 1 sec
(estimated error including systematics).
 
The time-averaged spectrum from T-13.8 to T+24.3 is best fit by a simple
power-law model.  The power law index of the time-averaged spectrum is
2.42 +- 0.30.  The fluence in the 15-150 keV band is 3.1 +- 0.5 x 10^-7 erg/cm2.
The 1-sec peak photon flux measured from T-13.76 sec in the 15-150 keV band
is 0.3 +- 0.1 ph/cm2/sec.  All the quoted errors are at the 90%
confidence level.