GCN Circular 253
Christian Veillet reports: The optical transient (OT) associated with the gamma ray burst GRB990123 has been observed with the new wide field camera CFH12k at the prime focus of the 3.6-m CFH Telescope for three consecutive nights on 1999 Feb 5.6, 6.6 and 7.6 by C. Veillet in the course of the French GRB follow-up program at CFHT (M. Boer, CESR, C. Veillet, CFHT). A composite image of the field around the OT has been made from eighteen 10min exposures (six per night). Using the standards published by Nilakshi et al. (GCN 252), the mean R magnitude of the OT averages to R = 23.45 (0.1) on 1999 Feb 6.6. Images of the field, with a detection limit of R=25.0 (3 sigma), can be seen at the Web site http://www.cfht.hawaii.edu/~veillet/grb990123.html. No object is detected in a radius of 5" centered on the OT. This message may be cited.