GCN Circular 1024

Further Optical Observations of GRB 010324

J. S. Bloom, P. A. Price, D. W. Fox, S. G. Djorgovski (CIT), and
J. M. Schombert (U. Oregon) report on behalf of the larger
Caltech-NRAO-CARA GRB Collaboration:

"On 26.27 March 2001, we obtained a second night of exposures of the
field of GRB 010324 (GCN/RXTE ASM; Hurley et al., GCN #1011) using
COSMIC on the Palomar 200-inch atop Mt. Palomar.  Using the same
pattern as in the first epoch of imaging (GCN #1012), the entire XTE
error box was observed in V-band in two pointings with a total of 1800
sec per pointing.

Both image differencing and differential aperture photometry between
the two epochs revealed no obviously varying source.  No absolute
photometry for the field is available at this time.  However, adopting
V = 19.1 mag for a USNO A2.0 star at RA: 07:11:26.301, DEC:
+19:58:30.32 (J2000) we estimate the absence of variation by more than
0.3 mag down to V = 22.3 mag.

Sources brighter than V~18.5 mag were saturated however all such sources
were previously observed in DPOSS (see GCN #1012); therefore any GRB
afterglow is now likely to be faint (V > 22.3 mag). One caveat to this
conclusion is that the GRB field has a high stellar density and so it is
possible to have missed a varying source near a bright star."

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