TITLE: GCN GRB OBSERVATION REPORT NUMBER: 4909 SUBJECT: GRB 060323: BVRI observations at Tautenburg, aftreglow candidate DATE: 06/03/23 23:17:25 GMT FROM: Alexander Kann at TLS Tautenburg D. A. Kann, B. Stecklum (TLS Tautenburg) report: The field of GRB 060323 (Vetere et al., GCN 4904) was observed with the 1.34m Tautenburg Schmidt telescope under excellent conditions in BVRcIc. The observation log is the following: Midtime Exp Filter lim. Mag 0.1948 6 * 600 s Ic 21.8 0.2227 1 * 600 s Rc 22.5 0.2309 1 * 600 s V 22.5 0.2385 1 * 600 s B 22.5 Limiting magnitudes were derived via comparison with SDSS pre-burst observations (Cool et al., GCN 4905). For the star at RA= 174.38742 (11:37:32.98) Dec = +50.02251 (+50:01:21.04) I derive via the transformation equations of Lupton (2005) and the SDSS photometry: B = 19.187 V = 18.848 Rc = 18.654 Ic = 18.002 with typical erros of 0.03 mags. Aperature photometry instrumental magnitudes are then compared with the magnitudes of sources near the detection limit. The limiting magnitudes may be improved with further analysis. There is no source detected at the position of the possible UVOT afterglow (Vetere et al., GCN 4904). At the position of the X-ray afterglow (Kennea et al., GCN 4908), we detect a faint source (Rc ~ 21) at RA= 11:37:44.56 Dec = +49:58:59.8 that is not visible in the SDSS (limiting mag ~ r = 23). We suggest this source as the possible afterglow of GRB 060323. This message may be cited.