TITLE:   GCN CIRCULAR
NUMBER:  17093
SUBJECT: GRB 141121A: Mondy optical observations
DATE:    14/11/24 16:56:28 GMT
FROM:    Alexei Pozanenko at IKI, Moscow  <apozanen@iki.rssi.ru>

E. Mazaeva (IKI), E. Klunko (ISTP), A. Volnova (IKI), M. Eselevich 
(ISTP), I. Korobtsev (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., 23  starting on 
(UT) 20:57:39.  We obtained several  images in R-filter. In a combined 
image we clearly  detect optical  afterglow (Tanga et al., GCN 17078; 
Perley et al., GCN 17081).

A preliminary photometry is based on nearby SDSS  stars:

date       UT start   t-T0     Filter   Exp.    OT    OT_err
                               (mid, days)       (s)

2014-11-23 20:57:39   2.74025  R        39*120  20.53 0.04

We confirm re-brightening of the afterglow reported early (Watson et al. 
GCN 17090; Kuroda et al. GCN  17091; Dichiara  et al. GCN 17092).