M31Y eclipsing binaries and Cepheids

The first step is to search for detached eclipsing binaries (DEBs) and Cepheids using 1m class telescopes to select good candidates, which will be followed up spectroscopically on 6.510m class telescopes. In this ninth paper, we present a catalog of variable stars discovered with image subtraction in field M31Y (RA=10.97{deg}, DE=41.69{deg}; J2000.0).

The data were obtained with the Fred Lawrence Whipple Observatory 1.2m telescope on 25 nights, over a period of 6 months. In our search covering 22x22, we discovered 41 eclipsing binaries, 126 Cepheids, and 97 other periodic or nonperiodic variables, including a luminous blue variable candidate, a nova, and a Galactic cataclysmic variable. The catalog of variables, as well as their photometry and finding charts, is available electronically via anonymous ftp and the World Wide Web, at cfa-www.harvard.edu/~kstanek/DIRECT .