[vsnet-grb-info 16356] GRB 150323C, Swift-BAT refined analysis

[GCN Circulars]

TITLE:   GCN CIRCULAR
NUMBER:  17637
SUBJECT: GRB 150323C, Swift-BAT refined analysis
DATE:    15/03/24 20:28:56 GMT
FROM:    Amy Lien at GSFC  <amy.y.lien at nasa.gov>

D. M. Palmer (LANL), Amaral-Rogers (U Leicester), 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-274 to T+800 sec from the recent telemetry downlink,
we report further analysis of BAT GRB 150323C (trigger #636005)
(Amaral-Rogers, et al., GCN Circ. 17621).  The BAT ground-calculated position is
RA, Dec = 192.625, 50.165 deg which is
  RA(J2000)  =  12h 50m 30.1s
  Dec(J2000) = +50d 09' 55.3"
with an uncertainty of 2.4 arcmin, (radius, sys+stat, 90% containment).
The partial coding was 26%.

The mask-weighted light curve shows several weak overlapping pulses. The main
burst structure starts at ~ T-20 s and ends at ~T+20 s, followed by another weaker
pulse lasting till ~ T+160 s. T90 (15-350 keV) is 159.4 +- 54.0 sec (estimated error
including systematics).

The time-averaged spectrum from T-22.9 to T+166.3 sec is best fit by a simple
power-law model.  The power law index of the time-averaged spectrum is
2.09 +- 0.32.  The fluence in the 15-150 keV band is 1.3 +- 0.3 x 10^-6 erg/cm2.
The 1-sec peak photon flux measured from T+5.98 sec in the 15-150 keV band
is 1.1 +- 0.3 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/636005/BA/