[vsnet-grb-info 15850] GRB 141121A: Mondy optical observations

[GCN Circulars]

TITLE:   GCN CIRCULAR
NUMBER:  17138
SUBJECT: GRB 141121A: Mondy optical observations
DATE:    14/12/05 14:58:30 GMT
FROM:    Alexei Pozanenko at IKI, Moscow  <apozanen at iki.rssi.ru>

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 continue observations of the field of GRB 141121A (Lien et al., GCN 
17075) with AZT-33IK telescope of Sayan observatory (Mondy). We obtained 
several  images in R-filter on Nov., 30, Dec. 1 - 2. In a combined image 
we detect optical  afterglow (Tanga et al., GCN 17078; Perley et al., 
GCN 17081).

A preliminary photometry of the OT is based on nearby SDSS DR9 stars:

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

2014-11-30 18:45:29    9.7139  R       119*120  22.20 0.10
2014-12-01 18:35:23   10.6644  R        72*120  22.25* 0.17
2014-12-02 18:09:52   11.6606  R        92*120  22.40* 0.25



*)Due to bad seeing the photometry  includes both afterglow and nearby 
source (Watson et al., GCN 17105; Mazaeva et al., GCN 17111).