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A variational formalism for tidal excitation: non-rotating, homentropic stars

Yasser Rathore·Avery E. Broderick·Roger Blandford
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Abstract

We present a variational formalism for describing the dynamical evolution of an oscillating star with a point-mass companion in the linear, non-relativistic regime. This includes both the excitation of normal modes and the back-reaction of the modes on the orbit. The general formalism for arbitrary fluid configurations is presented, and then specialized to a homentropic potential flow. Our formalism explicitly identifies and conserves both energy and angular momentum. We also consider corrections to the orbit up to 7/2 post-Newtonian order.

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Yasser Rathore, Avery E. Broderick, Roger Blandford. 2002-09-03. A variational formalism for tidal excitation: non-rotating, homentropic stars. https://doi.org/10.1046/j.1365-8711.2003.06140.x

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