TITLE:   GCN CIRCULAR
NUMBER:  15411
SUBJECT: GRB 131030A: 1.23m CAHA BVRI-band observations
DATE:    13/10/31 02:14:28 GMT
FROM:    Javier Gorosabel at IAA-CSIC  <jgu@iaa.es>

V. Terron (IAA/CSIC), M. Fernandez (IAA/CSIC), J. Gorosabel (IAA/CSIC-UPV/EHU), report on behalf of a larger collaboration:

We imaged the GRB131030A (GCNC 15402) optical afterglow (GCNC 15403, 15405, 14506, 15410) with the 1.23m CAHA telescope. Two BVRI-band series were taken starting 2.01 hr post burst. The optical afterglow is well detected in the four bands at a level of R~18.0 (Vega), calibrated against the USNO B1.0 catalog.