H. A. Krimm (GSFC/USRA),S. D. Barthelmy (GSFC), W. H. Baumgartner (GSFC/UMBC),
J. R. Cummings (GSFC/UMBC), N. Gehrels (GSFC),A. Y. Lien (NASA/UMBC),
C. B. Markwardt (GSFC), D. M. Palmer (LANL), J. L. Racusin (NASA/GSFC),T.
M. Stamatikos (OSU),J. Tueller (GSFC),T. N. Ukwatta (MSU)
(i.e. the Swift-BAT team):
Using the data set from T-239 to T+423 sec from the recent telemetry downlink,
we report further analysis of BAT GRB 140311A (trigger #591390)
(Racusin, et al., GCN Circ. 15944). The BAT ground-calculated position is
RA, Dec = 209.293, 0.607 deg which is
RA(J2000) = 13h 57m 10.4s
Dec(J2000) = +00d 36' 23.9"
with an uncertainty of 3.8 arcmin, (radius, sys+stat, 90% containment).
The partial coding was 10%.
The mask-weighted light curve shows two weak peaks, the first from roughly T-5
sec to T+5 sec and the second from approximately T+40 to T+60 sec. T90 (15-350
keV) is 71.4 +- 9.5 sec (estimated error including systematics).
The time-averaged spectrum from -4.456 to 83.736 sec is best fit by a simple
power-law model. The power law index of the time-averaged spectrum is
1.67 +- 0.23. The fluence in the 15-150 keV band is 2.3 +- 0.3 x 10^-6 erg/cm2.
The 1-sec peak photon flux measured from T-2.40 sec in the 15-150 keV band
is 1.3 +- 0.5 ph/cm2/sec. All the quoted errors are at the 90% confidence
The results of the batgrbproduct analysis are available at