TITLE:   GCN CIRCULAR
NUMBER:  12131
SUBJECT: GRB 110709B : A possible source in USNO B 1.0
DATE:    11/07/10 01:49:29 GMT
FROM:    L.P. Xin at NAOC  <xlp@bao.ac.cn>

L. P. Xin and J.Y Wei reports:

We noted that A. J. Levan reports (GCN 12126) that a source 
was detected in USNO-A2.0, with a magnitude of B=21.2, R=17.9.

Its coordinates are:
RA(J2000): 10:58:37.34
DEC(J2000): -23:27:21.6
Epoch:(J2000)

We check the USNO-B1.0 catalog and find that this source above 
reported by Levan (GCN 12126) disappeared in USNO-B1.0 catalog.
However, another source was detected in USNO-B1.0
at the errorbox of X-ray counterparts.

Its coordinates are 
RA(J2000) 10:58:37.00
DEC(J2000) -23:27:19.94
Epoch:(J2000)
Its magnitudes are reported as R=19.69, B=21.08.

The coordinates are consistent with the report of Updike et al. (GCN 12129).

Further observations are encouraged, especially the redshift measurement,
to check out weather this source is the counterpart of GRB 110709B or 
just a foreground or background source.