[vsnet-grb-info 25671] GRB 200519A: Swift-BAT refined analysis

[GCN Circulars]

TITLE:   GCN CIRCULAR
NUMBER:  27771
SUBJECT: GRB 200519A: Swift-BAT refined analysis
DATE:    20/05/21 03:38:57 GMT
FROM:    Amy Lien at GSFC  <amy.y.lien at nasa.gov>

M. Stamatikos (OSU), S. D. Barthelmy (GSFC),
J. R. Cummings (CPI), H. A. Krimm (NSF),
S. Laha (GSFC/UMBC), A. Y. Lien (GSFC/UMBC),
C. B. Markwardt (GSFC), D. M. Palmer (LANL),
T. Sakamoto (AGU), B. Sbarufatti (PSU),
T. N. Ukwatta (LANL) (i.e. the Swift-BAT team):

Using the data set from T-61 to T+242 sec from the recent telemetry
downlink,
we report further analysis of BAT GRB 200519A (trigger #973140)
(Sbarufatti et al., GCN Circ. 27756).  The BAT ground-calculated position is
RA, Dec = 255.319, -30.393 deg which is
   RA(J2000)  =  17h 01m 16.6s
   Dec(J2000) = -30d 23' 35.6"
with an uncertainty of 1.0 arcmin, (radius, sys+stat, 90% containment).
The partial coding was 99%.

The mask-weighted light curve shows a multi-peaked structure that starts
at ~T0 and ends at ~T+100 s. The three main peaks occur at ~T+1 s, ~T+24 s,
and ~T+75 s, respectively. T90 (15-350 keV) is 71.88 +- 1.28 sec (estimated
error including systematics).

The time-averaged spectrum from T-0.45 to T+103.00 sec is best fit
by a simple power-law model.  The power law index of the time-averaged
spectrum is 1.42 +- 0.03.  The fluence in the 15-150 keV band
is 1.2 +- 0.02 x 10^-05 erg/cm2. The 1-sec peak photon flux measured
from T+23.53 sec in the 15-150 keV band is 20.6 +- 0.5 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/973140/BA/