ROSAT DETECTION OF STELLAR X-RAY SOURCES IN THE OLD OPEN CLUSTER M-67

We have obtained a deep pointing on the old open cluster M 67 with the ROSAT PSPC. The detected X-ray sources show a strong concentration towards the optical cluster which leads us to believe that most of the sources are actually associated with M 67. In particular, our observation shows an X-ray counterpart for the cataclysmic variable recently discovered in M 67 (cf. Gilliland et al. 1991). Further, a larger fraction of the X-ray sources identified with M 67 cluster members are binaries as determined from optical studies, and we show that the X-ray properties of these stars make them good candidates for RS CVn systems in M 67.