[vsnet-grb-info 1953] GRB 050813: Photometry of object in XRT error circle

[GCN Circulars]

TITLE:   GCN GRB OBSERVATION REPORT
NUMBER:  3792
SUBJECT: GRB 050813: Photometry of object in XRT error circle
DATE:    05/08/13 16:31:55 GMT
FROM:    Edo Berger at Carnegie Obs  <eberger at ociw.edu>

E. Berger (Carnegie Observatories) reports:

"Inspection of DSS and 2MASS images reveals a single bright source on the
SE edge of the XRT error circle (GCN 3790) of GRB 050813 (GCN 3788) 
located at:
        RA = 16:07:57.39
        DEC = 11:14:42.95

Photometry of this source obtained from the 2MASS and USNO-B catalogs
suggests that this object is most likely a star, and not a bright
elliptical galaxy.  In particular, J-K = 0.4 mag and B-K = 2.3 mag, as
opposed to J-K ~ 1-1.3 mag and B-K ~ 4.3-5.4 mag for a typical elliptical
galaxy at redshifts of 0.1-0.3 (similar to the redshifts of previous short
bursts).

The photometry is as follows:
B = 16.61 mag
R = 15.67 mag
I = 14.72 mag
J = 14.68 mag
H = 14.37 mag
K = 14.28 mag