  We report the largest number of optical identifications of X-ray sources yet
obtained in a single globular cluster. Using deep Chandra/ACIS-I imaging and
extensive HST studies with WFPC2, we have detected optical counterparts to at
least 22 cataclysmic variables (CVs) and 29 chromospherically active binaries
(BY Dras and RS CVns) in 47 Tuc. These identifications are all based on tight
astrometric matches between X-ray sources and objects with unusual (non main
sequence) optical colors and/or optical variability. In the U vs U-V color
magnitude diagram (CMD), the CVs all show evidence for blue colors compared to
the main sequence, but most of them fall close to the main sequence in the V vs
V-I CMD, showing that the secondary stars dominate the optical light. The X-ray
detected active binaries have magnitude offsets above the main sequence that
are indistinguishable from those of the much larger sample of optical variables
(eclipsing and contact binaries and BY Dras) detected in the WFPC2 studies of
Albrow et al. (2001). We also present the results of a new, deeper search for
optical companions to MSPs. One possible optical companion to an MSP (47 Tuc T)
was found, adding to the two optical companions already known. Finally, we
study several blue stars with periodic variability from Albrow et al. (2001)
that show little or no evidence for X-ray emission. The optical colors of these
objects differ from those of 47 Tuc (and field) CVs.
