[vsnet-grb-info 15756] GRB 141109A: Swift-BAT refined analysis

[GCN Circulars]

TITLE:   GCN CIRCULAR
NUMBER:  17044
SUBJECT: GRB 141109A: Swift-BAT refined analysis
DATE:    14/11/09 18:02:52 GMT
FROM:    Scott Barthelmy at NASA/GSFC  <scott at lheamail.gsfc.nasa.gov>

W. H. Baumgartner (GSFC/UMBC), S. D. Barthelmy (GSFC), J. R. Cummings (GSFC/UMBC),
P. D'Avanzo (INAF-OAB), N. Gehrels (GSFC), H. A. Krimm (GSFC/USRA),
A. Y. Lien (GSFC/UMBC), C. B. Markwardt (GSFC), 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-239 to T+963 sec from recent telemetry downlinks,
we report further analysis of BAT GRB 141109A (trigger #618024)
(D'Avanzo, et al., GCN Circ. 17037).  The BAT ground-calculated position is
RA, Dec = 144.563, -0.581 deg, which is 
   RA(J2000)  =  09h 38m 15.0s 
   Dec(J2000) = -00d 34' 52.4" 
with an uncertainty of 3.0 arcmin, (radius, sys+stat, 90% containment).
The partial coding was 60%.
 
The mask-weighted light curve shows a weak peak from ~T+0 to ~T+40 sec,
then the bulk of the emission came from ~T+60 to ~T+190 sec,  and then a tail
extending out to ~T+380 sec.  T90 (15-350 keV) is 200 +- 47 sec
(estimated error including systematics).
 
The time-averaged spectrum from T+0.60 to T+323.15 sec is best fit by a simple
power-law model.  The power law index of the time-averaged spectrum is
1.52 +- 0.07.  The fluence in the 15-150 keV band is 6.8 +- 0.3 x 10^-6 erg/cm2.
The 1-sec peak photon flux measured from T+117.39 sec in the 15-150 keV band
is 2.5 +- 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/618024/BA/