  We present an optically-selected catalog of 1073 galaxy cluster and group
candidates at 0.3<z<1. These candidates are drawn from the Las Campanas Distant
Clusters Survey (LCDCS), a drift-scan imaging survey of a 130 square degree
strip of the southern sky. To construct this catalog we utilize a novel
detection process in which clusters are detected as positive surface brightness
fluctuations in the background sky. This approach permits us to find clusters
with significantly shallower data than other matched-filter methods that are
based upon number counts of resolved galaxies. Selection criteria for the
survey are fully automated so that this sample constitutes a well-defined,
homogeneous sample that can be used to address issues of cluster evolution and
cosmology. Estimated redshifts are derived for the entire sample, and an
observed correlation between surface brightness and velocity dispersion (sigma)
is used to estimate the limiting velocity dispersion of the survey as a
function of redshift. We find a net surface density of 15.5 candidates per
square degree at z_{est}>0.3, with a false-detection rate of 30%. At z=0.3 we
probe down to the level of poor groups while by z=0.8 we detect only the most
massive systems (sigma>1000 km/s). We also present a supplemental catalog of
112 candidates that fail one or more of the automated selection criteria, but
appear from visual inspection to be bona fide clusters.
