GRB 000201

M. Boer, J.L. Atteia, A. Klotz, CESR/CNRS communicates:

TAROT has imaged the position of  BATSE trigger 7976 on Feb. 1, 2000, at
03:02UT. A transient source appears at T0 + 55min, consistent with the
BATSE LOCBURST and the IPN positions (K. Hurley, private communication).
No prior image of this source has been acquired, because it is too far
from the BATSE FINAL position. The source is at the following 2000.0
position: 9h 16m 08.8 +18d 06' 13", +-5" and its apparent unfiltered
magnitude is 15 +-1. We could not see it on subsequent frames taken at
least 30 min after. We  warn potential observers that a high background
of unidentified transient sources has been observed in this region,
though it is the only one in the IPN error box. The TAROT image is at
the following URL: http://www.cesr.fr/~boer/tarot/GRB000201.html

This message is citable.

R. Kehoe (Univ. of Michigan), J. Wren, R. Balsano (Los Alamos) and 
B. Lee (Fermilab) report on behalf of the ROTSE collaboration (U.
Michigan/LANL/LLNL).

We have observed the error box of GRB000201 provided by the Final and
LocBurst Position Notices dated 1-Feb-00 using the ROTSE-I telephoto
camera array.  The initial BACODINE Notice localization fell below our
elevation cut and was not observed.  The ROTSE-I trigger protocol for  
Final Notices begins with 20 second exposures for the first few frames
followed by 80 second exposures thereafter.  All LocBurst response images
are 80 second exposures.  We have searched the LocBurst 1 sigma error
region in the first half hour of observations and found no significantly
varying objects.  We have also searched all images at the location of
the optical transient described in GCN #535
Loading...
 
  at RA = 139.03667, DEC =
18.10361 (J2000).  For the nine LocBurst observations, this position falls
in the overlap region between cameras 'a' and 'd', giving a degree of
redundancy.  The times and sensitivities (5 sigma cut-off) of these
observations are:

         observation #   time - T0 (s)   limiting magnitude
         -------------   -------------   ------------------
         1-7             85.9 to 322             14.1
         8-16            329 to 634              14.3
         17-41           641 to 3055             15.1
	 38-41 co-add	 2689 to 3055		 15.8

No object is detected at the transient location in any image in any camera.  
To further explore the possibility of a dim counterpart, we have co-added
the last four LocBurst images (see Table).  No object is detected at the 
transient location in this image.  Given our observation that any source
at this location is around mag. 16 or dimmer within 5 minutes of the TAROT
position, we believe this is not the optical counterpart to GRB000201.
Further analysis to explore the wider field is in progress.

This message may be cited.

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

"Starting on February 10.15 UT we used the VLA to observe a field
centered at the position of the optical transient identified by Boer,
Atteia and Klotz (GCN 535
Loading...
 
 ). There are no radio sources above a 3-sigma
threshold of 0.18 mJy within a 10-arcsecond radius of the OT."

This message may be cited.