T. Sakamoto (AGU), S. D. Barthelmy (GSFC),
H. A. Krimm (NSF), S. Laha (GSFC/UMBC),
A. Y. Lien (U Tampa), C. B. Markwardt (GSFC),
D. M. Palmer (LANL), T. Parsotan (GSFC/UMBC),
M. Stamatikos (OSU) (i.e. the Swift-BAT team):
Using the data set from T-240 to T+40 sec sec from the recent telemetry downlink,
we report further analysis of BAT GRB 220412B (trigger #1102329)
(Gropp et al. GCN Circ. 31886). The BAT ground-calculated position is
RA, Dec = 320.758, -0.261 deg which is
RA(J2000) = 21h 23m 01.9s
Dec(J2000) = -00d 15' 38.5"
with an uncertainty of 1.6 arcmin, (radius, sys+stat, 90% containment).
The partial coding was 75%.
The BAT light curve showed a single-peaked
structure. T90 (15-350 keV) is 0.14 +- 0.04 sec
(estimated error including systematics).
The time-averaged spectrum from T-0.03 to T+0.16 sec is best fit by a simple
power-law model. The power law index of the time-averaged spectrum is
1.17 +- 0.20. The fluence in the 15-150 keV band is 8.9 +- 1.2 x 10^-08 erg/cm2.
The 1-sec peak photon flux measured from T-0.44 sec in the 15-150 keV band
is 1.0 +- 0.2 ph/cm2/sec. All the quoted errors are at the 90% confidence
The results of the batgrbproduct analysis are available at