TITLE: GCN CIRCULAR NUMBER: 12728 SUBJECT: GRB 111225A: 1.23m CAHA optical observations DATE: 11/12/25 22:59:12 GMT FROM: Javier Gorosabel at IAA-CSIC J. Gorosabel (IAA-CSIC), P. Martorell (Obs. Guirguillano), P. Kubanek (IAA-CSIC & U. Valencia), S. Mottola (DLR, Berlin), report on behalf of a larger collaboration: "We have observed the field of GRB 111225A (Siegel et al. GCNC 12720) with the 1.23m CAHA telescope. The observations were carried out in Dec 25.74725 - 25.83561 UT (14.1--16.2 hours post burst) in the R-band with a total exposure time of 11x300+15x180s. We detect the optical afterglow of the burst with an R-band magnitude of R=21.60+/-0.16, with respect to the USNO B1.0 catalogue."