Very Wide Binary Stars as the Primary Source of Stellar Collisions in the Galaxy

Abstract

We present numerical simulations modeling the orbital evolution of very wide binaries, pairs of stars separated by over ~1000 AU. Due to perturbations from other passing stars and the Milky Way's tide, the orbits of very wide binary stars occasionally become extremely eccentric, which forces close encounters between the companion stars (Kaib et al. 2013). We show that this process causes a stellar collision between very wide binary companion stars once every 1000-7500 years on average in the Milky Way. One of the main uncertainties in this collision rate is the amount of energy dissipated by dynamic tides during close (but not collisional) periastron passages. This dissipation presents a dynamical barrier to stellar collisions and can instead transform very wide binaries into close or contact binaries. However, for any plausible tidal dissipation model, very wide binary stars are an unrealized, and potentially the dominant, source of stellar collisions in our Galaxy. Such collisions should occur throughout the thin disk of the Milky Way. Stellar collisions within very wide binaries should yield a small population of single, Li-depleted, rapidly rotating massive stars.

13 pages, 11 figures, accepted to ApJ

References in corpus (6)

• New Distant Companions to Known Nearby Stars. II. Faint companions of Hipparcos stars and the frequency of wide binary systems
• The triple evolution dynamical instability: Stellar collisions in the field and the formation of exotic binaries
• Injection of Oort Cloud Comets: The Fundamental Role of Stellar Perturbations
• 2MASS J05162881+2607387: A New Low-Mass Double-Lined Eclipsing Binary
• The Great Escape III: Placing post-main-sequence evolution of planetary and binary systems in a Galactic context
• Dynamical tides excited in rotating stars of different masses and ages and the formation of close in orbits

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