[vsnet-grb-info 20315] GRB 180205A: BAO optical observations

[GCN Circulars]

TITLE:   GCN CIRCULAR
NUMBER:  22411
SUBJECT: GRB 180205A: BAO optical observations
DATE:    18/02/11 10:53:10 GMT
FROM:    Alexei Pozanenko at IKI, Moscow  <apozanen at iki.rssi.ru>

A. Volnova (IKI),  A. Novichonok (KIAM), A. Pozanenko (IKI), S. Kotov  (SAO 
RAS), T. Movsesyan (BAO),  E. Mazaeva (IKI)  report on behalf of of
larger GRB follow-up collaboration:

We observed the field of GRB 180205A (Evans  et al., GCN 22381) with 
Schmidt-1m telescope of Byurakan Astrophysical Observatory (BAO).  We took 
several images in r (Sloan)-filter  starting on Feb. 08 (UT) 12:54:29.  The 
afterglow of GRB 180205A (Evans et al., GCN 22381; Zheng et al. GCN 22382; 
Bolmer et al. GCN 22383;Tanvir et al. GCN 22384; Volnova et al. GCN 22387; 
Falcon et al. GCN 22380; Xin et al. GCN 22392; Zhu et al. GCN 22395; Emery 
et al. GCN  22396; Im et al., GCN 22397; Oksanen et al. 22401; Mazaeva et 
al., GCN 22403)  is  clearly detected in a stacked image. Preliminary 
photometry  is following.

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


2018-02-08  18:00:00  3.59550    r     12*300 21.3    0.2  21.9

The photometry is based on several nearby SDSS DR9 stars

SDSS_id                         r
J082719.98+113324.0 16.357 0.005
J082717.26+113400.0 16.292 0.005
J082715.06+113230.6 15.744 0.004