TITLE:   GCN CIRCULAR
NUMBER:  36255
SUBJECT: GRB 240419A: Swift-BAT refined analysis
DATE:    24/04/23 13:00:27 GMT
FROM:    Mike Moss at NASA GSFC <mikejmoss3@gmail.com>

T. Parsotan (GSFC), S. D. Barthelmy (GSFC),
H. A. Krimm (NSF), S. Laha (GSFC/UMBC),
A. Y. Lien (U Tampa), C. B. Markwardt (GSFC),
M. J. Moss (GSFC), D. M. Palmer (LANL),
T. Sakamoto (AGU), M. H. Siegel (PSU)
(i.e. the Swift-BAT team):
 
Using the data set from T-60 to T+243 sec from the recent telemetry downlink,
we report further analysis of BAT GRB 240419A (trigger #1222955)
(Siegel, et al., GCN Circ. 36169).  The BAT ground-calculated position is
RA, Dec = 94.505, -44.964 deg which is
   RA(J2000)  =  06h 18m 01.3s
   Dec(J2000) = -44d 57' 50.2"
with an uncertainty of 3.0 arcmin, (radius, sys+stat, 90% containment).
The partial coding was 89%.
 
The mask-weighted light curve shows two dim pulses at T0-7 s and T0+0 s,
respectively.
The T90 (15-350 keV) is 3.00 +- 1.41 sec (estimated error including systematics).
 
The time-averaged spectrum from T-0.43 to T+2.57 sec is best fit by a simple
power-law model.  The power law index of the time-averaged spectrum is
1.71 +- 0.38.  The fluence in the 15-150 keV band is 8.4 +- 2.1 x 10^-08 erg/cm2.
The 1-sec peak photon flux measured from T+0.57 sec in the 15-150 keV band
is 0.6 +- 0.1 ph/cm2/sec.  All the quoted errors are at the 90% confidence
level.
 
The results of the batgrbproduct analysis are available at
https://swift.gsfc.nasa.gov/results/batgrbcat/BAT_refined_circular/1222955