GCN Circular 3313
P.A. Price (IfA), T. Minezaki (U. Tokyo), L. Cowie (IfA) and Y. Yoshii (U. Tokyo) report on behalf of the UH-MAGNUM GRB collaboration: We observed the XRT position of GRB 050421 (Godet et al., GCN #3301) with the automated MAGNUM telescope + MIP dual-beam optical-NIR imager, commencing at April 21.57 UTC (9.4 hours after the GRB). We obtained 9x60 sec images in JHK, reaching limiting magnitudes of J ~ 20.3 mag, H ~ 19 mag, K ~ 18.6 mag (from comparison with a single 2MASS star). We do not detect any afterglow candidate in the XRT error circle. This message may be cited.