PROPERTIES OF THE EXCEPTIONALLY LONG-PERIOD AM HERCULIS SYSTEM RX J0515.41+0104.6

We show that the properties of the recently discovered AM Her type cataclysmic variable RX J0515.41+0104.6 can be understood in terms of the standard evolutionary model, which accounts for both the near-synchronism at the observed period and the size of the mass-donor star. We find that either the system is in a low state long enough to bring the white dwarf to synchronism or that the magnetic field of the secondary is strong enough, but not unusually so (greater than or similar to 1 kG), to maintain synchronism at this period and the system may exhibit radio flares.