GCN Circular 13420
B. E. Cobb (GWU) reports: Using the ANDICAM instrument on the 1.3m telescope at CTIO, we obtained optical/IR imaging of the error region of GRB 120703A (GCN 13408, Zhang et al.) with a mid-exposure time of 13.7 hours post-burst (2012-07-04 07:07 UT). Total summed exposure times amounted to 15 minutes in I and V and 12 minutes in J and K. No source is detected at the position of the optical afterglow (e.g. GCN 13411, Xu et al.; GCN 13418, Swenson et al.) to approximate limiting magnitudes of I > 20.5, J > 18.5 and K > 17.4. Magnitudes are calibrated using USNO-B1.0 stars in I, and 2MASS stars in J and K.