[vsnet-grb-info 25813] GRB 200608A: Swift-BAT refined analysis

[GCN Circulars]

TITLE:   GCN CIRCULAR
NUMBER:  27913
SUBJECT: GRB 200608A: Swift-BAT refined analysis
DATE:    20/06/09 19:07:12 GMT
FROM:    Amy Lien at GSFC  <amy.y.lien at nasa.gov>

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

Using the data set from T-239 to T+963 sec from the recent telemetry
downlink,
we report further analysis of BAT GRB 200608A (trigger #976692)
(Moss et al., GCN Circ. 27906).  The BAT ground-calculated position is
RA, Dec = 309.628, -31.194 deg which is
   RA(J2000)  =  20h 38m 30.7s
   Dec(J2000) = -31d 11' 39.4"
with an uncertainty of 2.3 arcmin, (radius, sys+stat, 90% containment).
The partial coding was 53%.

The mask-weighted light curve shows several overlapping pulses that start
at ~T+20 s and ends at ~T+150 s. The two main peaks occur at
~T+18 s and ~T+70 s, respectively. There may be an additional weak pulse
at ~T-100 s. T90 (15-350 keV) is 119.2 +- 34.7 sec (estimated error
including systematics).

The time-averaged spectrum from T+18.09 to T+147.94 sec is best fit by a
simple
power-law model.  The power law index of the time-averaged spectrum is
2.05 +- 0.22.  The fluence in the 15-150 keV band is 1.5 +- 0.2 x 10^-6
erg/cm2.
The 1-sec peak photon flux measured from T+70.29 sec in the 15-150 keV band
is 0.7 +- 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/976692/BA/