TITLE: GCN GRB OBSERVATION REPORT NUMBER: 4836 SUBJECT: GRB200618: optical polarimetry and photometry DATE: 06/02/26 15:25:13 GMT FROM: Valeri Larionov at NIAI SpBU V. Larionov and L.Larionova from St.Petersburg University (Russia) , report: We imaged GRB20060218 with 70-cm telescope of Crimean Astrophysical observatory (Ukraine) and ST-7 camera of St.Petersburg University in photometric and polarimetric mode. Observations were made in R band from February 20.17 to February 23.18. The rate of brightening in this period was 0.18 mag/day. The polarization reached maximum of 6% on February 21 and decreased to 3% on February 23. The positional angle remained practically unchanged, 110+\-5 deg. The high and variable polarization gives evidence of strongly aspherical or non-thermal component in GRB20060218/SN2006aj radiation. This message is citeable.