TITLE:   GCN CIRCULAR
NUMBER:  18679
SUBJECT: GRB 151210A: Optical afterglow candidate from LCOGT-Cerro Tololo
DATE:    15/12/10 05:33:13 GMT
FROM:    Dong Xu at NAOC/CAS  <dxu@nao.cas.cn>

Yanhui Han (NAOC/CAS, HUST), Thomas Kruehler (ESO), Dong Xu (NAOC/CAS), 
Youdong Hu (IAA-CSIC), and Yin Qing (Geneva Observatory) report:

We observed the field of GRB 151210A (Evans et al., GCN 18678) with the 
1-m LCOGT telescope at Cerro Tololo, Chile. Observations started 
03:34:06 UT on 2015-12-10 (i.e., 21.2 mins after the GRB), and we 
obtained 10x240s R-band images.

Within the XRT error circle (Evans et al., GCN 18678), an uncatalogued 
optical source is detected in our stacked image at coordinates:

R. A. = 04:20:28.048
Dec. = -71:15:02.53

with an error radius of ~0.5 arcsec. The object roughly has R~21.5 mag, 
calibrated with the nearby USNO B1 field. We thus consider that the 
source is very likely the optical afterglow of GRB 151220A.