[vsnet-grb-info 16389] GRB 150323C: additional optical observations in Mondy

[GCN Circulars]

TITLE:   GCN CIRCULAR
NUMBER:  17670
SUBJECT: GRB 150323C: additional  optical observations in Mondy
DATE:    15/04/04 11:16:29 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 additionally observed the field of the GRB 150323C (Amaral-Rogers  et 
al., GCN 17621) with AZT-33IK telescope of Sayan observatory (Mondy) on 
Mar., 27 and Mar. 30 under good weather conditions and mean FWHV of 1.8 
arcsec. We obtained several images in R-filter of 120 s  exposure. In both 
epochs we detect a source in coordinates (J2000) 12 50 27.90 +50 11 29.0 
(+/- 0.45" ) which is within afterglow coordinates (Xu et al., GCN 17625) 
and within the enhanced Swift-XRT position (Osborne et al., GCN 17633). Our 
object is apparently the same object suggested as a possible host galaxy 
(Malesani et al., GCN 17655). Preliminary photometry of the source is 
following

Date       UT start           t-T0        Filter   Exp.       OT    Err.
                                       (mid, days)       (s)

2015-03-27 18:22:30   4.11333  R        85*120  22.7 0.25
2015-03-30 14:09:29   7.02068  R      194*120  22.3 0.15

Photometry is based on SDSS DR9 stars:

SDSS9_id            R(Lupton)
J125023.08+501048.2 16.84
J125032.04+501021.5 18.37

Also we note that our photometry reported early (Mazaeva et al., GCN 17639) 
may by significantly  be significantly influenced by the possible  host 
galaxy.