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arXiv · 0705.1938

The extraordinary LBV/WR system HD 5980

Gloria Koenigsberger·Edmundo Moreno
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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, E-dot, associated with turbulent viscosity are orbital-phase dependent as well as variable over the stellar surface. We speculate that if E-dot 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 theta~30 --50 degrees during part of the orbital cycle. Thus, the analysis of wind-wind interactions in this system requires that models be revised to incorporate non-stationary and asymmetric wind structures.

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Gloria Koenigsberger, Edmundo Moreno. 2007-05-14. The extraordinary LBV/WR system HD 5980. https://arxiv.org/abs/0705.1938

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