TITLE:   GCN CIRCULAR
NUMBER:  20701
SUBJECT: LIGO/Virgo G274296: Optical Observation
DATE:    17/02/19 15:04:19 GMT
FROM:    Myungshin Im at Seoul National U  <myungshin.im@gmail.com>

M. Im, S. Lee, C. Choi, G. Lim, S. Hwang, H. M. Lee (SNU), S. Pak, T.-G. Ji
(KHU), H.-I. Sung (KASI), S. Ehgamberdiev (UBAI) on behalf of the
KU collaboration

We observed a 49 square degree of the probability area of G274296 using a
wide-field 0.25m telescope (a piggyback system on the 0.8m telescope) at
the McDonald observatory, Texas, USA. The observation was performed in
R-band, starting at 2017-02-18 11:27 (UT). A preliminary analysis of the
data shows the detection limit of  R ~ 17.8 mag at 5-sigma for a point
source detection. The covered fields are indicated below, each having a
2.35 deg x 2.35 deg field of view centered at the coordinates. The central
parts of the fields are covered by the 0.8m telescope simultaneously,
covering 46.2 arcmin x 46.2 arcmin field of view to the depths about 0.7
magnitude deeper than the 0.25m data. The analysis of the data is ongoing.

Field    RA                Dec
G1:  12:10:00.00   40:30:00.0
G2:  12:10:00.00   38:00:00.0
G3:  12:10:00.00   35:30:00.0
G4:  12:20:00.00   40:30:00.0
G5:  12:20:00.00   38:00:00.0
G6:  12:20:00.00   35:30:00.0
G7:  12:30:00.00   40:30:00.0
G8:  12:30:00.00   38:00:00.0
G9:  12:30:00.00   35:30:00.0

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