GCN Circular 24164
Subject
GRB 190424A: Swift-BAT refined analysis
Date
2019-04-24T21:26:50Z (5 years ago)
From
Amy Lien at GSFC <amy.y.lien@nasa.gov>
M. Stamatikos (OSU), S. D. Barthelmy (GSFC), J. R. Cummings (CPI),
J.D. Gropp (PSU), H. A. Krimm (NSF/USRA), A. Y. Lien (GSFC/UMBC),
C. B. Markwardt (GSFC), D. M. Palmer (LANL), T. Sakamoto (AGU),
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 190424A (trigger #900285)
(Group, et al., GCN Circ. 24163). The BAT ground-calculated position is
RA, Dec = 48.693, 20.239 deg which is
RA(J2000) = 03h 14m 46.2s
Dec(J2000) = +20d 14' 19.9"
with an uncertainty of 1.4 arcmin, (radius, sys+stat, 90% containment).
The partial coding was 41%.
The mask-weighted light curve shows a single, fairly symmetrical pulse
starting
at T-2 seconds, peaking at T+2 sec, and declining to background by T+12 sec.
The spacecraft slewed away from the burst location at T+80 sec.
T90 (15-350 keV) is 10.6 +- 2.3 sec (estimated error including systematics).
The time-averaged spectrum from T-1.31 to T+12.04 sec is best fit by a
simple
power-law model. The power law index of the time-averaged spectrum is
1.45 +- 0.13. The fluence in the 15-150 keV band is 1.2 +- 0.1 x 10^-6
erg/cm2.
The 1-sec peak photon flux measured from T+1.10 sec in the 15-150 keV band
is 2.0 +- 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/900285/BA/