TITLE: GCN CIRCULAR NUMBER: 17111 SUBJECT: GRB 141121A: Mondy optical observations DATE: 14/11/28 19:21:59 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 observed the field of GRB 141121A (Lien et al., GCN 17075) with AZT-33IK telescope of Sayan observatory (Mondy) on Nov., 27 starting (UT) 19:13:37. We obtained several images in R-filter ander favorable weather and mean FWHM of 1.8 arcsec. In a combined image we clearly detect optical afterglow (Tanga et al., GCN 17078; Perley et al., GCN 17081). We do not detect the nearby source reported in (Watson et al., GCN 17075). Instead of we detect a Source (possible host?) 3 arcsec to the West from OT. The Source is absent in SDSS DR9. Coordinates of the OT and the Source are OT (J2000) 08 10 40.55 +22 13 03.0 with accuracy of 0.4" in both coordinates The Source to the West (J2000) 08 10 40.35 +22 13 03.0 with accuracy of 0.5" in both coordinates Astrometry solutions are based on USON-B1.0 catalog. A preliminary photometry of the OT is based on nearby SDSS stars: date UT start t-T0 Filter Exp. OT OT_err (mid, days) (s) 2014-11-27 19:13:37 6.6923 R 72*120 21.57 0.05 And preliminary photometry of the Source is R 22.95 ± 0.11. The source is barely visible in our earlier observations (Mazaeva et al., GCN 17102) and photometry of the early observation reported in (Mazaeva et al., GCN 17102) might be biased of this Source. The finding chart can be found in http://grb.rssi.ru/GRB141121A/GRB141121A.Mondy_host_chart.png