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GCN Circular 16773

GRB 140901B found in ground analysis of BAT data
2014-09-04T13:59:36Z (10 years ago)
Jay R. Cummings at NASA/GSFC/Swift <>
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
(, within the GBM error

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.
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