Optical Identification of Faint X‐Ray Sources in the Core of ω Centauri

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Abstract
We present the results of a search for optical counterparts of three faint X-ray sources in the core of NGC 5139 (ω Cen) with the HST Wide Field Planetary Camera 2. Using images taken through the F656N (Hα), F675W, and F336W filters, we have identified two stars with strong Hα and UV excesses, one in each of two of the X-ray error circles, and a possible optical counterpart in the third. The absolute magnitudes, broadband colors, and inferred emission-line strengths of all three stars are typical of cataclysmic variables (CVs). Further comparisons of the disk properties of the two strong candidates to CVs in the field strengthen our conclusion that they are promising CV candidates.