THE OPTICAL GRAVITATIONAL LENSING EXPERIMENT - VARIABLE-STARS IN GLOBULAR-CLUSTERS .2. FIELDS 5139D-F IN OMEGA CENTAURI

Three fields located close to the center of the globular cluster omega Cen were surveyed in a search for variable stars. We present V-band l ight curves for 32 periodic variables. This sample includes 10 SX Phe stars, 19 eclipsing binaries, and three likely spotted variables (FK C om or RS CVn type stars). Only 5 of these variables were previously kn own (including two objects reported in Paper I). All SX Phe stars and 8 eclipsing binaries from our sample belong to blue stragglers. Five b inaries occupy positions on the upper main-sequence of the cluster and another four are located at the base of the subgiant branch. Of parti cular interest is detection of a detached binary system with a period P = 4.64 day. Further study of this star can provide direct informatio n about properties of turnoff stars in omega Cen. All SX Phe stars and most of eclipsing binaries discovered in our survey are likely cluste r members. We present V vs. V - I color-magnitude diagrams for the mon itored fields. A populous group of likely hot subdwarfs as well as num erous candidates for blue stragglers can be noted in these diagrams. O ur data indicate that omega Cen possesses the largest number of blue s tragglers among all galactic globulars.