PRECESSIONAL LIGHT CURVES OF SS-433

We have calculated theoretical light curves of SS 433 during precessio n, using a model in which SS 433 consists of a geometrically thick tor us around a compact star and a companion star filling the Roche lobe. In order to interpret a bright hump at the precession phase of 0 (the torus is seen from the ''bottomside''), the configuration of the torus is not very thick, but should be rather thin (at least mildly thin). Combinations of light curves during eclipse and precession impose seve ral constraints on the physical parameters: the binary mass ratio, tor us configuration, and surface temperature of the companion. The favori te combination is a mass ratio of about 2 (a compact star is a black h ole) and a surface temperature of the companion of around 17000 K.