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Numerical study of the tidal interaction of a star and a massive black hole

J. A. Marck·A. Lioure·S. Bonazzola
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Abstract

We present a formalism well adapted to the numerical study of the encounter of an ordinary main sequence star with a massive black hole. Symmetry considerations, the use of a well adapted moving grid and a well adapted moving frame along with integration of the partial differential equations by means of pseudo-spectral methods result in a very powerful and accurate tool. The hydrodynamical equations are written in a moving frame which mimics the bulk of the movement of the fluid, resulting in very small relative velocities and a well suited spatial resolution throughout the calculations. Therefore, the numerical calculations are considerably simplified, smoothing in particular the Courant condition. Typical runs are performed within a few hours on a workstation with the high accuracy linked to the spectral methods. Predictions of the so-called affine are tested against this full numerical simulation.

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J. A. Marck, A. Lioure, S. Bonazzola. 1995-05-10. Numerical study of the tidal interaction of a star and a massive black hole. https://arxiv.org/abs/astro-ph/9505027

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