TITLE:   GCN CIRCULAR
NUMBER:  26897
SUBJECT: GRB 200125A: Swift-BAT refined analysis
DATE:    20/01/27 18:18:42 GMT
FROM:    Amy Lien at GSFC  <amy.y.lien@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),
M. Stamatikos (OSU), T. N. Ukwatta (LANL)
(i.e. the Swift-BAT team):

Using the data set from T-170 to T+808 sec from the recent telemetry
downlink,
we report further analysis of BAT GRB 200125A (trigger #952164)
(Lien et al., GCN Circ. 26876).  The BAT ground-calculated position is
RA, Dec = 228.069, -8.142 deg which is
   RA(J2000)  =  15h 12m 16.6s
   Dec(J2000) = -08d 08' 31.3"
with an uncertainty of 1.8 arcmin, (radius, sys+stat, 90% containment).
The partial coding was 42%.

The mask-weighted light curve shows a multi-pulse structure that starts
at ~T-40 s and ends at ~T+430 s. The three main pulses occurs at ~T0,
~T+200 s, and ~T+300 s, respectively. The highest peak is at ~T+287 s.
The burst went out of the BAT FOV at T+501 s. T90 (15-350 keV)
is 350.83 +- 34.03 sec (estimated error including systematics).

The time-averaged spectrum from T-36.22 to T+427.74 sec is best fit by a
simple
power-law model.  The power law index of the time-averaged spectrum is
1.95 +- 0.08.  The fluence in the 15-150 keV band is 8.7 +- 0.4 x 10^-6
erg/cm2.
The 1-sec peak photon flux measured from T+286.67 sec in the 15-150 keV band
is 4.0 +- 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/952164/BA/