Very Large Telescope Observations of the Peculiar Globular Cluster NGC 6712: Discovery of a UV, Hα-Excess Star in the Core

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Abstract
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 Hα 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.
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