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GCN Circular 623

GRB000301C - R magnitude lower limit
2000-04-05T01:33:30Z (24 years ago)
Christian Veillet at CFHT <>
The candidate for the optical transient (OT) associated with the gamma 
ray burst  GRB000301C has been observed using the CFH12K CCD mosaic 
camera at the prime focus of the 3.6-m CFH Telescope in the course of 
the French GRB  follow-up  program at CFHT (M. Boer, CESR,  C. Veillet, 

Three 12 mn exposures with moderate seeing (image quality around 0.9") have
been coadded.

There is nothing visible at the location of the OT. The nearby galaxy 
(thought to be the host for some time before the HST observations) has a 
magnitude of R= 24.5 +-0.1, confirming the previous determinations (GCN592 
- GCN598).
The faintest objects detected in the neighborhood are at around R=26.

We can infer the following lower limit:
R > 26.0 on 2000 April 4.6 

It is compatible with the alpha = -2.7 power law decay given in GCN611, and 
not with alpha  = -2.1 given earlier, which would lead to R~25.6 at the
same epoch.

Further imaging is planned if the seeing gets better.

Jean-Charles Cuillandre is acknowledged for his help in this observation. 

This message may be cited. 

Dr. Christian Veillet,       CFHT Senior Resident Astronomer
Phone: (808) 885-3161
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