Interacting Winds and Giant Eruptions in Massive Binaries

Massive stars eject strong winds that affect their evolution. When in a binary system, their winds collide and emit radiation across the spectrum, providing an opportunity to study the stars and the interaction between them. There are many physical effects involved in the colliding-wind problem, and its complexity requires 3D numerical simulations. When one of the star is accreting the simulations become more complex. We present simulations of colliding winds in massive binary systems that include a detailed treatment of wind ejection, orbital motion, clumpiness, and other effects. These simulations are applied to different kinds of massive binaries that include LBVs, WR-stars, B[e] Supergiants, and O stars, in various primary–secondary combinations. We present results of simulations from some of the systems we studied. We show systematic simulations that were used to determine the general conditions that may lead to accretion onto the secondary star, and obtain the new sub-Bondi–Hoyle–Lyttleton accretion, with relationships between the mass accretion rate and the ratio of the stellar wind momentum. We also present recent results showing how the accreting secondary star responds to very high accretion rates, such as in giant LBV eruptions, and show how jets can suppress the accretion rate in such systems.