TITLE: GCN CIRCULAR NUMBER: 13199 SUBJECT: GRB 120320A: optical upper limit in Mondy observatory DATE: 12/04/03 18:25:11 GMT FROM: Alina Volnova at SAI MSU A.Volnova (SAI MSU),  I. Korobtsev, E. Klunko (ISTP), A. Pozanenko (IKI) on behalf of  larger GRB follow up collaboration report: We observed the field of the Swift GRB 120320A  (Markwardt  et al., GCN 13071) with AZT-33IK telescope of Sayan observatory (Mondy)  on Mar. 20 under mean seeing 2.6 arcsec. We took several images in R-filter of  60 s exposure on Mar.20, between (UT) 14:45:13 - 15:58:25. Within enhanced XRT position (Beardmore et al.,  GCN 13075) we do not detect any  source in a combined image. Photometry is based on nearby USNO-B1.0 stars, R2-values. UT start,    t-t0           filter      Exp.        OT      UL (3 sigma)               (mid, days)             (s) 14:45:13   0.14275    R       72x60         n/d      21.3