GCN Circular 5887
Subject
GRB 061202, Swift-BAT refined analysis
Date
2006-12-02T15:30:16Z (17 years ago)
From
Scott Barthelmy at NASA/GSFC <scott@lheamail.gsfc.nasa.gov>
T. Sakamoto (GSFC/ORAU), L. Barbier (GSFC), S. D. Barthelmy (GSFC),
J. Cummings (GSFC/UMBC), E. Fenimore (LANL), N. Gehrels (GSFC),
D. Hullinger (BYU-Idaho), H. Krimm (GSFC/USRA), C. Markwardt (GSFC/UMD),
D. Palmer (LANL), A. Parsons (GSFC), G. Sato (GSFC/ISAS),
M. Stamatikos (GSFC/ORAU), J. Tueller (GSFC)
on behalf of the Swift-BAT team:
Using the data set from T-239 to T+962 sec from recent telemetry downlinks,
we report further analysis of BAT GRB 061202 (trigger #241963)
(Sakamoto, et al., GCN Circ. 5886). The BAT ground-calculated position
is RA, Dec = 105.180, -74.587 deg which is
RA(J2000) = 07h 00m 43.2s
Dec(J2000) = -74d 35' 12.5"
with an uncertainty of 5.8 arcmin, (radius, sys+stat, 90% containment).
The partial coding was 76%.
The mask-weighted lightcurve shows that it started with low-level emission
at ~T-95 sec, then BAT triggered on a small peak at T+0 sec which returned
to instrumental background level at ~T+20 sec. Then some low level emission
starting at ~T+45 sec, then a much larger FRED peak started at ~T+70 sec,
peaking at T+75 sec, and ending at T+200 sec. T90 (15-350 keV) is 91 +- 5 sec
(estimated error including systematics).
The time-averaged spectrum from T-0.8 to T+147.4 is best fit by a simple
power-law model. The power law index of the time-averaged spectrum is
1.63 +- 0.07. The fluence in the 15-150 keV band is 3.5 +- 0.1 x 10^-6 erg/cm2.
The 1-sec peak photon flux measured from T+75.04 sec in the 15-150 keV band
is 2.6 +- 0.2 ph/cm2/sec. All the quoted errors are at the 90% confidence
level.