TITLE:   GCN CIRCULAR
NUMBER:  12815
SUBJECT: GRB 120106A: Swift-BAT refined analysis
DATE:    12/01/06 23:27:37 GMT
FROM:    Scott Barthelmy at NASA/GSFC  <scott@lheamail.gsfc.nasa.gov>

S. D. Barthelmy (GSFC), T. Sakamoto (GSFC/UMBC), W. H. Baumgartner (GSFC/UMBC),
J. R. Cummings (GSFC/UMBC), E. E. Fenimore (LANL), N. Gehrels (GSFC),
S. Immler (CRESST/GSFC/UMD), H. A. Krimm (GSFC/USRA), C. B. Markwardt (GSFC),
F. E. Marshall (NASA/GSFC), D. M. Palmer (LANL), G. Sato (ISAS),
M. Stamatikos (OSU), J. Tueller (GSFC), T. N. Ukwatta (MSU)
(i.e. the Swift-BAT team):
 
Using the data set from T-240 to T+962 sec from recent telemetry downlinks,
we report further analysis of BAT GRB 120106A (trigger #511235)
(Immler, et al., GCN Circ. 12810).  The BAT ground-calculated position is
RA, Dec = 66.129, 64.050 deg, which is 
   RA(J2000)  =  04h 24m 30.9s 
   Dec(J2000) = +64d 03' 00.0" 
with an uncertainty of 1.3 arcmin, (radius, sys+stat, 90% containment).
The partial coding was 75%.
 
The mask-weighted light curve shows the first peak starting at ~T-7 sec,
peaking at ~T+1 sec, and ending at ~T+13 sec. There is a second, weaker peak
starting at ~T+50 sec and ending at ~T+65 (possibly T+85) sec. 
T90 (15-350 keV) is 61.6 +- 4.1 sec (estimated error including systematics).
 
The time-averaged spectrum from T-6.24 to T+60.24 sec is best fit by a simple
power-law model.  The power law index of the time-averaged spectrum is
1.53 +- 0.17.  The fluence in the 15-150 keV band is 9.7 +- 1.1 x 10^-7 erg/cm2.
The 1-sec peak photon flux measured from T+0.46 sec in the 15-150 keV band
is 1.5 +- 0.2 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/511235/BA/