TITLE:   GCN CIRCULAR
NUMBER:  27742
SUBJECT: GRB 200512A: Swift-BAT refined analysis
DATE:    20/05/14 23:33:47 GMT
FROM:    Amy Lien at GSFC  <amy.y.lien@nasa.gov>

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

Using the data set from T-240 to T+962 sec from the recent telemetry
downlink,
we report further analysis of BAT GRB 200512A (trigger #971846)
(Simpson et al., GCN Circ. 27726).  The BAT ground-calculated position is
RA, Dec = 7.417, -2.217 deg which is
   RA(J2000)  =  00h 29m 40.2s
   Dec(J2000) = -02d 13' 01.1"
with an uncertainty of 1.5 arcmin, (radius, sys+stat, 90% containment).
The partial coding was 100%.

The mask-weighted light curve shows a single-pulse structure.
The main emission starts at ~T-3 s, peaks at ~T+3 s, and ends at
~T+40 s. In addition, there are some weak emission that lasts
until ~T+80 s. T90 (15-350 keV) is 74.0 +- 14.3 sec (estimated
error including systematics).

The time-averaged spectrum from T-2.86 to T+78.14 sec is best fit by a
simple
power-law model.  The power law index of the time-averaged spectrum is
1.68 +- 0.18.  The fluence in the 15-150 keV band is 8.1 +- 1.0 x 10^-7
erg/cm2.
The 1-sec peak photon flux measured from T+3.14 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/971846/BA/