[vsnet-grb-info 15758] GRB 141109B: Swift-BAT refined analysis

[GCN Circulars]

TITLE:   GCN CIRCULAR
NUMBER:  17046
SUBJECT: GRB 141109B: Swift-BAT refined analysis
DATE:    14/11/09 18:11:35 GMT
FROM:    Scott Barthelmy at NASA/GSFC  <scott at lheamail.gsfc.nasa.gov>

J. R. Cummings (GSFC/UMBC), S. D. Barthelmy (GSFC), W. H. Baumgartner (GSFC/UMBC),
N. Gehrels (GSFC), H. A. Krimm (GSFC/USRA), A. Y. Lien (GSFC/UMBC),
C. B. Markwardt (GSFC), A. Melandri (INAF-OAB), D. M. Palmer (LANL),
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-60 to T+243 sec from recent telemetry downlinks,
we report further analysis of BAT GRB 141109B (trigger #618032)
(Melandri, et al., GCN Circ. 17038).  The BAT ground-calculated position is
RA, Dec = 222.453, 73.141 deg, which is 
   RA(J2000)  =  14h 49m 48.8s 
   Dec(J2000) = +73d 08' 26.3" 
with an uncertainty of 2.6 arcmin, (radius, sys+stat, 90% containment).
The partial coding was 75%.
 
The mask-weighted light curve shows a couple overlapping peaks starting at 
~T-20 sec, peaking at ~T+28 sec, and ending at ~T+60 sec.
T90 (15-350 keV) is 54.2 +- 5.0 sec (estimated error including systematics).
 
The time-averaged spectrum from T-13.18 to T+44.18 sec is best fit by a simple
power-law model.  The power law index of the time-averaged spectrum is
1.85 +- 0.22.  The fluence in the 15-150 keV band is 6.3 +- 0.9 x 10^-7 erg/cm2.
The 1-sec peak photon flux measured from T+28.05 sec in the 15-150 keV band
is 0.4 +- 0.1 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/618032/BA/