THE LONG-TERM LIGHT-CURVE OF THE CATACLYSMIC VARIABLE DW URSAE MAJORIS

A 2.5-yr sequence of CCD photometry on DW Ursae Majoris has shown an unusual 4 mag fall and rise in the light curve. The rise appears relatively smooth and regular, unlike the transitions of other high-state/low-state systems. The effect could be due to solar-type magnetic variations on the secondary of the cataclysmic variable. Some observational as well as theoretical work suggests that a nova prior to outburst may show photometric behavior similar to that displayed by DW UMa.