TITLE:   GCN CIRCULAR
NUMBER:  22401
SUBJECT: GRB 180205A optical observations
DATE:    18/02/07 10:52:14 GMT
FROM:    Arto Oksanen at Nyrola Obs., Finland  <oksanen@nyrola.jklsirius.fi>

Arto Oksanen (Hankasalmi Obs., Hankasalmi, Finland) and D. Malesani (DARK/NBI) 
report the following observations of GRB 180205A (Evans et al., GCN 22381):

A. Oksanen observed the location of GRB 180205A using the Hankasalmi
Observatory 0.4-m Richey-Chretien telescope with an SBIG STL-1001E
camera. Forty 60-second frames were obtained with clear filter 
between 18:19 UT and 19:41 UT on 2018 February 5.
  
The afterglow is detected in co-added image.

Photometry of co-added image yields the following:

t-t0(d)     m(CR)   err(CR)
0.605       19.43    0.06

Photometry was performed using comparison stars from the Pan-STARRS survey 
(Chambers et al. 2016; arXiv:1612.05560), after adopting the conversion 
formulae by Lupton (2005).