TITLE:   GCN CIRCULAR
NUMBER:  33193
SUBJECT: GRB 230116C: Swift-BAT refined analysis
DATE:    23/01/18 22:23:03 GMT
FROM:    Sibasish Laha at GSFC  <sibasish.laha@nasa.gov>

A. Y. Lien (U Tampa), S. D. Barthelmy (GSFC),
H. A. Krimm (NSF), S. Laha (GSFC/UMBC),
C. B. Markwardt (GSFC), D. M. Palmer (LANL),
T. Parsotan (GSFC/UMBC), T. Sakamoto (AGU),
M. Stamatikos (OSU)(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 230116C (trigger #1149250)
(Sonbas et al., GCN Circ. 33173).  The BAT ground-calculated position is
RA, Dec = 223.467, -16.883 deg which is
   RA(J2000)  =  14h 53m 52.0s
   Dec(J2000) = -16d 52' 57.5"
with an uncertainty of 1.4 arcmin, (radius, sys+stat, 90% containment).
The partial coding was 65%.

The BAT light curve showed a complex structure with a duration of about 400 sec.
T90 (15-350 keV) is 316.77 +- 52.50 sec (estimated error including systematics).

The time-averaged spectrum from T-35.86 to T+346.68 sec is best fit by a simple
power-law model.  The power law index of the time-averaged spectrum is
1.72 +- 0.14.  The fluence in the 15-150 keV band is 6.1 +- 0.5 x 10^-06 erg/cm2.
The 1-sec peak photon flux measured from T+247.71 sec in the 15-150 keV band
is 0.8 +- 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/1149250/BA/