Abstract
The LBV/WR system HD 5980 contains a short-period, eccentric binary system with interacting stellar winds. In this paper we summarize results from model calculations of the tidal flows on the LBV component showing that energy dissipation rates, dot E, associated with turbulent viscosity are orbital-phase dependent as well as variable over the stellar surface. We speculate that if dot E contributes towards driving mass-loss, the strongest wind-wind interaction effects may occur after periastron passage. In addition, the model suggests the presence of stronger outflows localized at polar angles ∼ 30-50° than over the rest of the stellar surface during part of the orbital cycle. Thus, the analysis of wind-wind interactions in this system requires a modified model in which non-stationary and asymmetric wind structures are incorporated.
