TITLE: GCN CIRCULAR NUMBER: 12662 SUBJECT: GRB 111210A: GROND observations DATE: 11/12/11 12:31:25 GMT FROM: Sylvio Klose at TLS Tautenburg D. A. Kann, S. Klose (TLS Tautenburg), and J. Greiner, (MPE Garching) report on behalf of the GROND team: We observed the field of the Swift GRB 111210A (Swift trigger 509419; Siegel et al., GCN #12650) simultaneously in g'r'i'z'JHK with GROND (Greiner et al. 2008, PASP, 120, 405) mounted at the 2.2 m ESO/MPG telescope at La Silla Observatory (Chile). Observations started on December 11, 2011, at 08:06 UT, 0.73 days after the GRB trigger, during morning twilight and were partially performed only in the NIR. They were taken at an average seeing of 1".1 and at an airmass of 2 to 1.5. At the position of the X-ray afterglow (Goad et al., GCN #12652) as well as the optical candidate (Tanvir et al., GCN #12657), we tentatively detect a source in the redder filters. Based on co-added images of 743 s integration time in g'r'i'z' (centered 0.7396 days after the trigger) and 2160 s in JHK (centered 0.7520 days after the trigger), the following magnitudes and limits (3 sigma, AB magnitude system) have been derived: g' > 22.6, r' > 23.2, i' = 22.8 +/- 0.4, z' = 22.4 +/- 0.3, J = 21.4 +/ 0.3, H = 21.4 +/- 0.4, K > 20.5. Our r'-band upper limit is not deep enough to check fading against the Gemini North candidate. If the faint detections actually represents a real object, this is likely the host galaxy of this GRB (Tanvir & Malesani, GCN 12661). Magnitudes were calibrated against the SDSS catalog in g'r'i'z' and 2MASS field stars in JHK.