[ITAL]Hubble Space Telescope[/ITAL] Observations of the Post–Core-Collapse Globular Cluster NGC 6752: A Search for Cataclysmic Variables

We report the results of HST WFPC2 observations of the core of NGC 6752. We identify two candidate cataclysmic variables (CVs) from their strong narrowband Hα emission, periodic variability, and, in one case, a UV excess. We interpret the variability of these stars as being double-peaked, ellipsoidal light curves, in which case the orbital periods are 5.1 and 3.7 hr. The CV candidates fall at the edge of the error circle of one of the known X-ray sources in the cluster.