GCN Circular 13064
N. R. Tanvir (U. Leicester), D. Perley (Caltech), K. Wiersema (U. Leicester), A. Cucchiara (UCSC/UCO Lick), K. Roth (Gemini) and J. Ehle (JACH) report on behalf of a larger collaboration: We observed the location of GRB 120312A with Gemini-N/GMOS in the z-band and UKIRT/WFCAM in the J- and K-bands.�� All observations were obtained approximately 23 hours post-burst. With GMOS we detect the source reported by Tanvir et al. (GCN 13055). Calibrating against SDSS field stars we find a magnitude z=24.35 +- 0.12, indicating a fading compared to the WHT epoch, and confirming this source as the afterglow of the GRB. From a provisional reduction of the UKIRT data, the afterglow is undetected to 3-sigma limits of J=21.1 and K=19.5 (calibrated against 2MASS), showing that it is not extremely red, as might have been expected if its faintness were due to a very dusty line of sight.