TITLE: GCN CIRCULAR NUMBER: 23640 SUBJECT: GRB 190106A: Mondy optical observations DATE: 19/01/08 11:50:31 GMT FROM: Alexei Pozanenko at IKI, Moscow S. Belkin (IKI), E. Klunko (ISTP), A. Pozanenko (IKI), E. Mazaeva (IKI), A. Volnova (IKI), I. Reva (FAPI) report on behalf of IKI-FuN: We observed the optical afterglow (e.g. Lipunov et al. GCN 23616, Itoh et al. GCN 23617, Mao et al. GCN 23618, Reva et al., GCN 23620, Xin et al. GCN 23622, Quadri et al. GCN 23624, Hu et al. GCN 23627) of the GRB 190106A (Sonbas et al., GCN 23615) with AZT-33IK telescope of Sayan observatory (Mondy). We started observations on Jan. 06 (UT) 13:53:44, i.e. 19 minutes after burst trigger and continued observations on Jan. 07, Jan. 08 in R-filter. Preliminary light curve obtained on Jan. 06 observation can be found in http://grb.rssi.ru/GRB190106A/GRB190106A_LC_R.png The photometry is based on nearby SDSS stars SDSS-DR12_id R(Lupton) J015920.22+235150.7 16.475 J015929.35+235237.5 15.774