DWARF NOVA OUTBURSTS IN TRUNCATED ACCRETION DISCS - DOWN WITH LOW ALPHAS

We show that the long recurrence time of the outbursts of WZSge can be reproduced by an outside-in instability, in a disc, the inner part of which is removed by the magnetic field of the white dwarf. Contrary t o previous assertions, we demonstrate that an outburst interval of 30 yr does not require an anomalously low value for the viscosity paramet er in quiescence, but rather it can be obtained with a standard value. Nor does it require an increased mass transfer to trigger the outburs ts. A few observational tests of the proposed model are suggested.