TITLE: GCN CIRCULAR NUMBER: 17625 SUBJECT: GRB 150323C: Nanshan optical afterglow detection DATE: 15/03/23 18:10:39 GMT FROM: Dong Xu at DARK/NBI D. Xu (DARK/NBI), H.-B. Niu, J.-Z. Liu, G.-X. Pu, A. Esamdin, L. Ma (XAO) report: We observed the field of GRB 150323C (Amaral-Rogers et al., GCN 17621) using the 1m telescope at Nanshan, Xinjiang, China. Observations were carried out in R-band, starting at 17:19:50 UT on 2015-03-23, i.e., 869 s after the burst. A source, not present in SDSS and DSS, is well detected in individual images at coordinates RA(J2000) = 12:50:27.92 Dec(J2000) = +50:11:28.75 with an uncertainty of ~ 1 arcsec, being consistent with the enhanced Swift-XRT position (Evans, GCN 17624). We thus think it's the optical afterglow of the burst, and it has m(R) = 21.3 +/- 0.2 at a median time of 1344s post-burst, calibrated with the SDSS field.