TITLE: GCN CIRCULAR NUMBER: 17670 SUBJECT: GRB 150323C: additional optical observations in Mondy DATE: 15/04/04 11:16:29 GMT FROM: Alexei Pozanenko at IKI, Moscow E. Mazaeva (IKI), A. Volnova (IKI), E. Klunko (ISTP), I. Korobtsev (ISTP), M. Eselevich (ISTP), A. Pozanenko (IKI) report on behalf of larger GRB follow-up collaboration: We additionally observed the field of the GRB 150323C (Amaral-Rogers et al., GCN 17621) with AZT-33IK telescope of Sayan observatory (Mondy) on Mar., 27 and Mar. 30 under good weather conditions and mean FWHV of 1.8 arcsec. We obtained several images in R-filter of 120 s exposure. In both epochs we detect a source in coordinates (J2000) 12 50 27.90 +50 11 29.0 (+/- 0.45" ) which is within afterglow coordinates (Xu et al., GCN 17625) and within the enhanced Swift-XRT position (Osborne et al., GCN 17633). Our object is apparently the same object suggested as a possible host galaxy (Malesani et al., GCN 17655). Preliminary photometry of the source is following Date UT start t-T0 Filter Exp. OT Err. (mid, days) (s) 2015-03-27 18:22:30 4.11333 R 85*120 22.7 0.25 2015-03-30 14:09:29 7.02068 R 194*120 22.3 0.15 Photometry is based on SDSS DR9 stars: SDSS9_id R(Lupton) J125023.08+501048.2 16.84 J125032.04+501021.5 18.37 Also we note that our photometry reported early (Mazaeva et al., GCN 17639) may by significantly be significantly influenced by the possible host galaxy.