GCN Circular 14571
L. P. Xin, J. Y. Wei, Y. L. Qiu, J. Wang, J. S. Deng, C. Wu, X. H. Han report on behalf of EAFON team: We began to observe the field of GRB 130505A (Cannizzo, et al., GCN 14563) using 80cm TNT telescope located at Xinglong observatory, China at 12:25:39 UT on 2013-05-05. We obtained several R-band images. The reported optical counterpart (Cannizzo, et al., GCN 14563) is detected in all images. A prelinary analysis shows that its brightness is decaying from R~18.05 to R~18.68 mag during 4.05h and 4.85h after the trigger time. These magnitudes are calibrated with USNO B1.0 R2 stars, This message may be cited.