TITLE:   GCN CIRCULAR
NUMBER:  23717
SUBJECT: GRB 190114C: Optical observations
DATE:    19/01/15 15:50:04 GMT
FROM:    Myungshin Im at Seoul Nat U  <mim@astro.snu.ac.kr>

Myungshin Im, Gregory S. Paek, Sophia Kim, Gu Lim, Changsu Choi (CEOU/SNU),
on behalf of a larger collaboration

We observed the afterglow of GRB 190114C (Gropp et al., GCN 23688; Tyurina
et al., GCN 23690, de Ugarte Postigo et al., GCN 23692, Lipunov et al. GCN
23693, Selsing et al. GCN 23695, Izzo et al. GCN 23699, Bolmer et al. GCN
23702, Castro-Tirado et al. GCN 23708, Kann et al. GCN 23710) with the 0.8m
and 0.25m telescopes at the McDonald Observatory, and the 1.0m telescope at
the SNU Astronomical Observatory. The observation at the McDonald
observatory started at about 6.1 hours after the initial alert, and used B,
V, R filters.

We identify the afterglow in the McDonald observatory's data, and
preliminary photometry shows R = 18.9 +- 0.1 mag at 6.1 hours post-burst.

Further observations and analysis are being carried out.