[vsnet-grb-info 15484] GRB 140901B found in ground analysis of BAT data

[GCN Circulars]

TITLE:   GCN CIRCULAR
NUMBER:  16773
SUBJECT: GRB 140901B found in ground analysis of BAT data
DATE:    14/09/04 13:59:36 GMT
FROM:    Jay R. Cummings at NASA/GSFC/Swift  <james.r.cummings at nasa.gov>

J. R. Cummings reports on behalf of the Swift science team:

At 06:17:24 Swift-BAT rate-triggered on GRB 140901B (trigger # 611389).
Fermi-GBM also triggered on this event (trigger 431245045).  No source
was found onboard.  In ground analysis, a significant source was found
at RA, Dec 112.184, -29.209, which is
    RA (J2000)   07h 28m 44.2s
    Dec (J2000) -29d 12' 31"
with an estimated 90% uncertainty radius of 2.0 arcmin.  This location
is 3.0 degrees from the reported GBM location
(http://gcn.gsfc.nasa.gov/other/431245045.fermi), within the GBM error
circle.

The background in BAT was high, since Swift was near the SAA.  The BAT
lightcurve shows a single FRED peak, with T90 about 10 +- 1 sec.

The BAT spectrum with 10.0 seconds of data is best fit by a simple power-
law function with a photon index of 1.20 +- 0.22.  Using this model, the
fluence was (9.5 +- 1.3) x 10^-7 ergs/cm^2.  Errors are 90% confidence.

A Swift TOO request has been submitted, but this burst is already 3.5
days old, and moreover is rather close to the Sun.