GCN Circular 1727

K. Hurley and T. Cline, on behalf of the Ulysses and Mars Odyssey GRB teams,

I. Mitrofanov, D. Anfimov, A. Kozyrev, M. Litvak and A. Sanin,
on behalf of the HEND/Odyssey GRB team, and

W. Boynton, C. Fellows, K. Harshman, C. Shinohara and R. Starr,
on behalf of the GRS/Odyssey GRB team, report:

Ulysses and HEND observed this burst at 81155 +/- 1104 s.  The
uncertainty is due to the fact that no near-Earth spacecraft has yet
reported this event.  As observed by Ulysses, it had a duration of
approximately 20 seconds with a weak tail lasting perhaps another 40
seconds, a 25-100 keV fluence of approximately  1.6E-04 erg/cm2, and a
peak flux of approximately  2.9E-05 erg/cm2 s over 0.50 seconds.

We have triangulated it to a preliminary annulus centered at RA, Decl
(2000)= 328.915, -57.580 degrees, with radius 81.125 +/- 0.014
degrees.  (The uncertainty in the radius does not take into account the
fact that HEND was driven into saturation by this burst; we will
attempt to include this in later estimates).  As this annulus does not
pass near any of the known SGRs, we believe the event to be a GRB.

We are expecting confirmation of this event by a near-Earth spacecraft,
which will allow us to derive an error box for it.