GCN Circular 18725
Y. Kitaoka, T. Sakamoto, A. Yoshida (AGU) We observed the field of GRB 151212A detected by MAXI (Nakahira et al., GCN Circ. 18685) with the iTelescope.Net (http://www.itelescope.net) T18 (Plane Wave CDK) telescope located at the AstroCamp Observatory (Nerpio, Spain). 20 images of 60 sec exposures were taken in the Red filter starting from December 12 22:43:00 (UT) about 8.7 hours after the trigger and stopped on December 12 23:17:03 (UT). We do not detect the optical afterglow both in the individual images and the stacked image at the X-ray afterglow position (Roegiers et al., GCN Circ. 18687). The estimated five sigma upper limit of the combined image (total exposure of 1200 sec) is ~17.0 using the USNO-B1 catalog.