TITLE: GCN CIRCULAR NUMBER: 12004 SUBJECT: GRB 110503A: R-band Detection DATE: 11/05/05 00:43:08 GMT FROM: Myungshin Im at Seoul Nat U Myungshin Im (CEOU/Seoul National Univ), Hyun-Il Sung (KASI), and Yuji Urata (NCU) on behalf of EAFON We observed GRB 110503A (Stamatikos et al., GCN 11991) in R-band with a 1.0-m telescope at Mt. Lemmon, Arizona. The observation started at 05-04-03:24:30 UT. We detect the afterglow with a magnitude at R ~ 20.28 +- 0.09 mag (mid-time of ~10.0 hrs after BAT alert) based on the photometry calibration star reported by Updike et al.(GCN 12001). Further analysis of the data and the follow-up observations of the object is ongoing. We thank the LOAO operator, I.-K. Baek for her assistance with the observation.