T. Sakamoto (AGU), S. D. Barthelmy (GSFC), J. R. Cummings (GSFC/UMBC),
N. Gehrels (GSFC), H. A. Krimm (GSFC/USRA), A. Y. Lien (GSFC/UMBC),
C. B. Markwardt (GSFC), D. M. Palmer (LANL), M. Stamatikos (OSU),
T. N. Ukwatta (LANL)
(i.e. the Swift-BAT team):
Using the data set from T-60 to T+243 sec from the recent telemetry downlinks,
we report further analysis of BAT GRB 150819A (trigger #652643)
(Ukwatta, et al., GCN Circ. `8`63). The BAT ground-calculated position is
RA, Dec = 42.340, 9.787 deg, which is
RA(J2000) = 02h 49m 21.5s
Dec(J2000) = +09d 47' 11.6"
with an uncertainty of 2.8 arcmin, (radius, sys+stat, 90% containment).
The partial coding was 93%.
the mask-weighted light curve shows a broad peaking starting at ~T+10 sec,
peaking at ~T+40 sec, and ending at ~T+70 sec.
T90 (15-350 keV) is 52.1 +- 12.9 sec (estimated error including systematics).
The time-averaged spectrum from T+14.18 to T+73.46 sec is best fit by a simple
power-law model. The power law index of the time-averaged spectrum is
1.72 +- 0.27. The fluence in the 15-150 keV band is 4.8 +- 0.9 x 10^-7 erg/cm2.
The 1-sec peak photon flux measured from T+17.70 sec in the 15-150 keV band
is 0.3 +- 0.1 ph/cm2/sec. All the quoted errors are at the 90% confidence
The results of the batgrbproduct analysis are available at