TITLE: GCN CIRCULAR NUMBER: 23423 SUBJECT: GRB 181110A: optical observations in Chilescope observatory DATE: 18/11/11 18:27:48 GMT FROM: Alexei Pozanenko at IKI, Moscow S. Belkin (IKI), A. Pozanenko (IKI), E. Mazaeva (IKI), A. Volnova (IKI) report on behalf of IKI-FuN follow-up collaboration: We observed the field of GRB 181110A (Evans et al., GCN 23413) with RC-1000 telescopes of CHILESCOPE observatory. Observation started on Nov. 11 (UT) 01:02:08 in r'-filter and were performed under moderate seeing conditions of 1.5''. We detect optical afterglow (Evans et al., GCN 2341; Yamanaka et al., GCN 23414; Murata et al., GCN 23415; Denisenko et al., GCN 23416; Perley et al., GCN 23421; Bolmer et al., GCN 23422). Preliminary photometry in AB is following. Date UT start t-T0 Filter Exp. OT Err. UL (mid, days) (s) 2018-11-11 01:02:08 0.69979 r' 10*300 20.53 0.10 22.8 The photometry is based on several nearby stars, magnitudes taken from NOMAD catalog and Jester et al. (2005) transformations.