[vsnet-grb-info 25824] GRB 200612A: Swift-BAT refined analysis

[GCN Circulars]

TITLE:   GCN CIRCULAR
NUMBER:  27924
SUBJECT: GRB 200612A: Swift-BAT refined analysis
DATE:    20/06/13 01:19:49 GMT
FROM:    Sibasish Laha at GSFC  <sibasish.laha at nasa.gov>

C. B. Markwardt (GSFC), S. D. Barthelmy (GSFC),
J. R. Cummings (CPI), H. A. Krimm (NSF),
S. Laha (GSFC/UMBC), A. Y. Lien (GSFC/UMBC),
D. M. Palmer (LANL), T. Sakamoto (AGU),
E. Sonbas (Adiyaman Univ.), M. Stamatikos (OSU),
T. N. Ukwatta (LANL) (i.e. the Swift-BAT team):

Using the data set from T-60 to T+243 sec from the recent telemetry downlink,
we report further analysis of BAT GRB 200612A (trigger #977310)
(E. Sonbas et al., GCN Circ. 27915). The BAT ground-calculated position is
RA, Dec = 302.691, -45.354 deg which is
   RA(J2000)  =  20h 10m 45.8s
   Dec(J2000) = -45d 21' 12.7"
with an uncertainty of 1.5 arcmin, (radius, sys+stat, 90% containment).
The partial coding was 96%.

The mask weighted light curve shows a complex structure. The
overall structure starts at ~T-20 s and lasts till ~T+200 s.
T90 (15-350 keV) is 171.48 +- 19.74 sec (estimated error including systematics).

The time-averaged spectrum from T-11 to T+193 sec is best fit by a simple
power-law model.  The power law index of the time-averaged spectrum is
1.34 +- 0.09.  The fluence in the 15-150 keV band is 3.8 +- 0.2 x 10^-6 erg/cm2.
The 1-sec peak photon flux measured from T+4.03 sec in the 15-150 keV band
is 0.7 +- 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/977310/BA/