[vsnet-grb-info 15887] GRB 141212A: Swift-BAT refined analysis

[GCN Circulars]

TITLE:   GCN CIRCULAR
NUMBER:  17175
SUBJECT: GRB 141212A: Swift-BAT refined analysis
DATE:    14/12/13 05:02:51 GMT
FROM:    Tilan Ukwatta at MSU  <tilan.ukwatta at gmail.com>

D. M. Palmer (LANL), S. D. Barthelmy (GSFC),
W. H. Baumgartner (GSFC/UMBC), J. R. Cummings (GSFC/UMBC),
N. Gehrels (GSFC), H. A. Krimm (GSFC/USRA),
A. Y. Lien (GSFC/UMBC), C. B. Markwardt (GSFC),
T. Sakamoto (AGU), M. Stamatikos (OSU),
J. Tueller (GSFC), T. N. Ukwatta (LANL)
(i.e. the Swift-BAT team):

Using the data set from T-240 to T+962 sec from the recent
telemetry downlink, we report further analysis of BAT GRB
141212A (trigger #621229) (Ukwatta, et al., GCN Circ. 17158).
The BAT ground-calculated position is RA, Dec =
39.167, 18.163 deg which is
   RA(J2000)  =  02h 36m 40.1s
   Dec(J2000) = +18d 09' 47.1"
with an uncertainty of 1.9 arcmin, (radius, sys+stat, 90%
containment). The partial coding was 58%.

BAT light curve shows a strong FRED like peak starting
around T-0.05 sec and ending around T+0.2 sec. Another
softer peak can be seen starting at T+0.2 sec, peaking
at T+0.3 sec and ending around T+0.35 sec. T90 (15-350 keV)
is 0.30 +- 0.08 sec (estimated error including systematics).

The time-averaged spectrum from T+0.00 to T+0.34 sec is
best fit by a simple power-law model.  The power law index
of the time-averaged spectrum is 1.61 +- 0.23.  The fluence
in the 15-150 keV band is 7.2 +- 1.2 x 10^-08 erg/cm2.
The 1-sec peak photon flux measured from T-0.33 sec in
the 15-150 keV band is 1.2 +- 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/621229/BA/