[vsnet-grb-info 1749] GRB050709 : Chandra source optical counterpart

[GCN Circulars]

TITLE:   GCN GRB OBSERVATION REPORT
NUMBER:  3589
SUBJECT: GRB050709 : Chandra source optical counterpart
DATE:    05/07/13 12:35:11 GMT
FROM:    Brian Lindgren Jensen at U.of Copenhagen  <brian_j at astro.ku.dk>

GRB050709.94 : Chandra source optical counterpart

B. L. Jensen, U. G. Jørgensen, J. Hjorth, J. P. U. Fynbo, D. Watson,
J. M. Castro Cerón, K. Pedersen, H. Pedersen, J. Sollerman (DARK
Cosmology Centre, Niels Bohr Institute)

"Using the Danish 1.54m+DFOSC (La Silla), we have obtained R-band images
of the field of the SXC-source associated with GRB 050709.94 (Butler et
al., GCN#3570) for two nights (July 11.3 and 12.3 UT) under good
conditions (0.7" and 1.0" seeing, respectively). At the location of the
Chandra source (Fox et al., GCN#3585), we clearly detect the object
present on the DSS.

In the image with the best seeing (the first night), this object
resolves into two sources separated by about 1". The 0.5" Chandra
error-circle covers the fainter, eastern-most, of these two sources.

In the image from the second night, the objects are not clearly
resolved. Aperture photometry of both objects together in the two epochs
(at t+33h and t+56h) do not indicate significant R-band variability.

Images of the objects are shown at:
http://www.astro.ku.dk/~brian_j/grb/grb050709.94/ "