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Dynamical Friction for Compound Bodies

R. Domínguez-Tenreiro·M. A. Gómez-Flechoso
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Abstract

In the framework of the fluctuation-dissipation approach to dynamical friction, we derive an expression giving the orbital energy exchange experienced by a compound body as it moves interacting with a non homogeneous discrete background. The body is assumed to be composed of particles endowed with a velocity spectrum and with a non homogeneous spatial distribution. The Chandrasekhar formula is recovered in the limit of a point-like satellite with zero velocity dispersion and infinite temperature moving through an homogeneous infinite medium. In this same limit, but dropping the zero satellite velocity dispersion ($σ_S$) condition, the orbital energy loss is found to be smaller than in the $σ_S=0$ case by a factor of up to an order of magnitude in some situations.

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R. Domínguez-Tenreiro, M. A. Gómez-Flechoso. 1997-09-30. Dynamical Friction for Compound Bodies. https://doi.org/10.1111/j.1365-8711.1998.01224.x

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