[vsnet-grb-info 3223] GRB 060501: P60 Observations and Candidate Retraction

[GCN Circulars]

TITLE:   GCN GRB OBSERVATION REPORT
NUMBER:  5058
SUBJECT: GRB 060501: P60 Observations and Candidate Retraction
DATE:    06/05/02 21:09:49 GMT
FROM:    S. Bradley Cenko at Caltech  <cenko at srl.caltech.edu>

S. B. Cenko (Caltech) and D. B. Fox (Penn State) report on behalf of a
larger collaboration:

We have re-imaged the field of GRB 060501 (La Parola et al., GCN 5040)
with the automated Palomar 60-inch telescope.  5 x 150 s images were taken
in the i filter at a mean epoch of approximately 10:54 2 May 2006 UT (~
26.7 hours after the burst).  The afterglow candidate identified by Fox
and Cenko (GCN 5044; see also Halpern and Mirabal, GCN 5046) is clearly
visible and has not faded significantly since our previous observations,
over 24 hours earlier.  We therefore consider it unlikely to be the
afterglow of GRB 060501.

In addition, we find no evidence for variability in any sources in the
near vicinity of the XRT error circle (La Parola et al., GCN 5042).  We
re-iterate the following limits for any afterglow emission in the XRT
error circle from our previous notice:

Limiting Magnitude		Mean Time Since Burst
---------------------------------------------------------------------
I > 19.0			43 min
I > 21.0			92 min

No further observations are planned.