GRB 001025B

K. Hurley, on behalf of the Ulysses GRB team,
T. Cline, on behalf of the Konus-Wind and NEAR GRB teams,
and E. Mazets, and S. Golenetskii, on behalf of the KONUS-WIND GRB team, report:

Ulysses, NEAR, and KONUS-WIND observed this GRB at 71369 seconds.
As observed by Ulysses, it had a duration of  < 0.25 
seconds, a 25-100 keV fluence of approximately 2E-07 erg/cm2,
and a peak flux of approximately  8E-07 erg/cm2 s over 0.25 seconds
We have triangulated it to a preliminary, 3 sigma error
whose approximate area is 110. sq. arcmin. and whose
coordinates are:

    RA(2000)                              DEC(2000)
 ERROR BOX CENTER:  18 h 21 m 40.78 s     -5 o  8 '  34.45 " 
 ERROR BOX CORNER 1: 18 h 21 m 26.96 s     -5 o  8 '  54.58 " 
 ERROR BOX CORNER 2: 18 h 22 m 56.09 s     -5 o 22 '  40.46 " 
 ERROR BOX CORNER 3: 18 h 20 m 26.72 s     -4 o 54 '  38.26 " 
 ERROR BOX CORNER 4: 18 h 21 m 54.61 s     -5 o  8 '  14.39 " 

The duration and energy spectrum of this event place it clearly
in the short/hard category.  We add one note of caution: this
burst was detected by Ulysses with a significance of only 4.5
sigma (statistical), which is at the limit of a reliable detection.

This error box may be improved

E. Berger (Caltech) and D. A. Frail (NRAO), report on behalf of a larger
collaboration:

"Beginning on October 27.11 UT we observed the IPN error box of the
short/hard burst, GRB001025B (GCN #865
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 ) with the VLA at 4.86 GHz.  We find
no new sources which are not cataloged in the NRAO VLA Sky Survey (NVSS),
with a flux density larger than 0.7 mJy (5-6 sigma).

This message may be cited.

Alberto Castro-Tirado, IAA-CSIC (Granada) and  LAEFF-INTA (Madrid),
Manuel Alises, CAHA (Almeria),
Jochen Greiner, AIP (Potsdam),
on behalf of a larger collaboration, report:

"We have imaged the field of the short/hard GRB 001025B (Hurley et 
al., GCN 865
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 ) with the 2.2-m telescope at the German-Spanish Calar
Alto Observatory. Several frames covering about 95% of this low-
galactic latitude (4.4 deg) error box were obtained on Oct 27.85 UT, 
Oct 28.79 UT and Oct 29.78 UT (i.e. 48, 71 and 95 hours after the GRB).
No objects varying by more than 0.3 mag are seen within the error
box down to a limiting magnitude of I = 20.5."

[GCN OPS NOTE (31oct00):  There was a typo in the Circular as originally
distributed.  The "i.e. 24, 71..." phrase was changed to "i.e. 48, 71...".]

H. Park (LLNL), G. Williams (UA), D. Perez, R. Nemiroff (MTU), 
S. Barthelmy (GSFC), D. Hartmann, C. Laver (Clemson), 
K Hurley (UCB) report on behalf of the Super-LOTIS collaboration:

Super-LOTIS obtained images of the field around the short/hard burst 
GRB001025B (Hurley et al.,GCNC 865) with the 0.6-m Super-LOTIS telescope 
located at Kitt Peak, AZ on Oct 27.08 UT and 30.09 UT (30 and 102 hours 
after the burst) covering 100% of the IPN error box. The images were taken 
with 50 s integration time without a filter. A preliminary comparison 
of the two images revealed no new objects brighter than mV ~18.9
(10-sigma limit). Further analysis is in progress.

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