GCN Circular 6522
Subject
GRB 070612A, Swift-BAT refined analysis
Date
2007-06-12T20:36:55Z (17 years ago)
From
Scott Barthelmy at NASA/GSFC <scott@lheamail.gsfc.nasa.gov>
S. D. Barthelmy (GSFC), L. Barbier (GSFC), J. Cummings (GSFC/UMBC),
E. Fenimore (LANL), N. Gehrels (GSFC), D. Grupe (PSU),
H. Krimm (GSFC/USRA), C. Markwardt (GSFC/UMD), D. Palmer (LANL),
A. Parsons (GSFC), T. Sakamoto (GSFC/ORAU), G. Sato (GSFC/ISAS),
M. Stamatikos (GSFC/ORAU), J. Tueller (GSFC), T. Ukwatta (GWU)
(i.e. the Swift-BAT team):
Using the data set from T-239 to T+963 sec from the recent telemetry downlink,
we report further analysis of BAT GRB 070612A (trigger #282066)
(Grupe, et al., GCN Circ. 6509). The BAT ground-calculated position is
RA, Dec = 121.355, 37.258 deg which is
RA(J2000) = 8h 5m 25.2s
Dec(J2000) = 37d 15' 30"
with an uncertainty of 1.4 arcmin, (radius, sys+stat, 90% containment).
The partial coding was 11%.
The mask-weighted light curve shows two main overlapping peaks
with the first starting at ~T-20 sec and the second ending at ~T+400 sec.
The two peaks are at T+5 and T+200 sec. T90 (15-350 keV) is 370 +- 10 sec
(estimated error including systematics).
The time-averaged spectrum from T-4.7 to T+418 sec is best fit by a simple
power-law model. The power law index of the time-averaged spectrum is
1.69 +- 0.10. The fluence in the 15-150 keV band is 1.1 +- 0.1 x 10^-5 erg/cm2.
The 1-sec peak photon flux measured from T+10.39 sec in the 15-150 keV band
is 1.5 +- 0.4 ph/cm2/sec. All the quoted errors are at the 90% confidence
level.