IDENTIFICATION OF NEW LOW-MASS MEMBERS OF THE ALPHA-PERSEI OPEN CLUSTER BY ROSAT - II

The present investigation examines possible optical counterparts to 13 0 X-ray sources in the region of the alpha Persei open cluster (d simi lar to 170pc, age similar to 50 Myr) resulting from the analysis of th ree 22-25 ksec ROSAT PSPC pointings. In the same manner as for 73 X-ra y sources from a raster survey in alpha Per (Prosser & Randich 1998), CCD photometry is employed to obtain magnitudes and colors for stars/o bjects close to the X-ray positions, with additional echelle and low-d ispersion H alpha spectra provided for some stars. For almost 60 X-ray sources, an optical counterpart with photometry acceptable for cluste r membership is identified, some of which can be excluded from members hip on the basis of discrepant radial velocity or X-ray characteristic s. On the order of 30 new members or likely members associated with X- ray sources have been identified based on available data. A photometri c rotation period has been obtained for one rapid rotator identified i n X-rays.