TITLE:   GCN CIRCULAR
NUMBER:  29918
SUBJECT: GRB 210430A: Swift-BAT refined analysis
DATE:    21/05/01 00:02:11 GMT
FROM:    Amy Lien at GSFC  <amy.y.lien@nasa.gov>

H. A. Krimm (NSF), S. D. Barthelmy (GSFC),
J. R. Cummings (CPI), S. Laha (GSFC/UMBC),
A. Y. Lien (GSFC/UMBC), C. B. Markwardt (GSFC),
D. M. Palmer (LANL), T. Sakamoto (AGU),
B. Sbarufatti (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 210430A (trigger #1046014)
(Sbarufatti et al., GCN Circ. 29914).  The BAT ground-calculated
position is RA, Dec = 57.185, 45.080 deg which is
   RA(J2000)  =  03h 48m 44.3s
   Dec(J2000) = +45d 04' 46.9"
with an uncertainty of 1.7 arcmin, (radius, sys+stat, 90% containment).
The partial coding was 25%.

The mask-weighted light curve shows a single-peaked structure
that starts at ~T-3 s, peaks at ~T+2 s, and ends at ~T+15 s.
T90 (15-350 keV) is 11.53 +- 2.83 sec (estimated error including
systematics).

The time-averaged spectrum from T-2.72 to T+14.60 sec is best fit
by a simple power-law model.  The power law index of the time-averaged
spectrum is 2.15 +- 0.21.  The fluence in the 15-150 keV band is
9.9 +- 1.3 x 10^-7 erg/cm2. The 1-sec peak photon flux measured from
T+1.14 sec in the 15-150 keV band is 1.9 +- 0.4 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/1046014/BA/