TITLE:   GCN CIRCULAR
NUMBER:  29163
SUBJECT: GRB 201223A: Swift-BAT refined analysis
DATE:    20/12/24 01:56:53 GMT
FROM:    Amy Lien at GSFC  <amy.y.lien@nasa.gov>

S. Laha (GSFC/UMBC), S. D. Barthelmy (GSFC),
J.D. Gropp (PSU), H. A. Krimm (NSF),
A. Y. Lien (GSFC/UMBC), C. B. Markwardt (GSFC),
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+882 sec from the recent telemetry
downlink, we report further analysis of BAT GRB 201223A (trigger #1014316)
(Gropp et al., GCN Circ. 29158).  The BAT ground-calculated position is
RA, Dec = 132.735, 71.176 deg which is
   RA(J2000)  =  08h 50m 56.3s
   Dec(J2000) = +71d 10' 34.9"
with an uncertainty of 1.4 arcmin, (radius, sys+stat, 90% containment).
The partial coding was 53%.

The mask-weighted light curve shows a multi-peaked structure that
starts at ~T-25 s and ends at ~T+8 s. The main peak occurs at ~T0.
T90 (15-350 keV) is 29.0 +- 6.7 sec (estimated error including
systematics).

The time-averaged spectrum from T-25.18 to T+7.82 sec is best fit
by a simple power-law model.  The power law index of the time-averaged
spectrum is 1.35 +- 0.13.  The fluence in the 15-150 keV band is
1.3 +- 0.1 x 10^-06 erg/cm2. The 1-sec peak photon flux measured from
T-0.18 sec in the 15-150 keV band is 1.5 +- 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/1014316/BA/