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Dynamical Tide in Solar-Type Binaries

Jeremy Goodman·Eric S. Dickson
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Abstract

Circularization of late-type main-sequence binaries is usually attributed to turbulent convection, while that of early-type binaries is explained by resonant excitation of g modes. We show that the latter mechanism operates in solar-type stars also and is at least as effective as convection, despite inefficient damping of g modes in the radiative core. The maximum period at which this mechanism can circularize a binary composed of solar-type stars in 10 Gyr is as low as 3 days, if the modes are damped by radiative diffusion only and g-mode resonances are fixed; or as high as 6 days, if one allows for evolution of the resonances and for nonlinear damping near inner turning points. Even the larger theoretical period falls short of the observed transition period by a factor two.

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Jeremy Goodman, Eric S. Dickson. 1998-01-28. Dynamical Tide in Solar-Type Binaries. https://doi.org/10.1086/306348

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