Very large telescope observations of the peculiar globular cluster NGC 6712:: Discovery of a UV, Hα-excess star in the core

We present results from multiband observations in the central region of the cluster NGC 6712 with the ESO Very Large Telescope. Using high-resolution images we have identified three UV-excess stars. In particular, two of them are within the cluster core, a few arcseconds apart: the first object is star "S," which previous studies identified as the best candidate to the optical counterpart to the luminous X-ray source detected in this cluster. The other UV object shows clear-cut Ha! emission and, for this reason, is an additional promising interacting binary candidate (a quiescent low-mass X-ray binary or a cataclysmic variable). The presence of two unrelated interacting binary systems a few arcseconds apart in the core of this low-density cluster is somewhat surprising and supports the hypothesis that the (internal) dynamical history of the cluster and/or the (external) interaction with the Galaxy might play a fundamental role in the formation of these peculiar objects.