ROSAT high resolution imager observations of three magnetic cataclysmic variables: EP Draconis, EUVE J2115-58, and AR URSAE majoris

I present ROSAT HRI observations of the magnetic cataclysmic variables EP D ra, EUVE J72115 - 58, and AR UMa. The HRI light curve for EP Dra shows the typical polar behavior for one-pole accretion. When the data from a 1993 PS PC observation are phased correctly, the PSPC and HRI light curves appear n early identical in behavior. The eclipses differ in width, however. The PSP C eclipse is about half the width of the HRI eclipse, suggesting that the H RI eclipse is a combined eclipse and stream occultation. The EUVE J2115-58 observation was obtained in two parts approximately 180 days apart. The cou nt rates differ by a factor of 3 between the two epochs. The X-ray data do not resolve the period ambiguity, because the light curves look very simila r when folded on every published period. A period search using the longer o bservation yields two periods of 102.6 and 110.4 minutes. The HRI observati on for AR UMa occurred during an off state. AR UMa is detected at a signifi cance level of 3 sigma at a luminosity of similar to 4 x 10(29) ergs s(-1), which likely arises from the M dwarf companion.