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arXiv · 2112.10709

Symplectic coarse graining approach to the dynamics of spherical self-gravitating systems

Luca Barbieri·Pierfrancesco Di Cintio·Guido Giachetti·Alicia Simon-Petit·Lapo Casetti
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Abstract

We investigate the evolution of the phase-space distribution function around slightly perturbed stationary states and the process of violent relaxation in the context of the dissipationless collapse of an isolated spherical self-gravitating system. By means of the recently introduced symplectic coarse graining technique, we obtain an effective evolution equation that allows us to compute the scaling of the frequencies around a stationary state, as well as the damping times of Fourier modes of the distribution function, with the magnitude of the Fourier $k-$vectors themselves. We compare our analytical results with $N$-body simulations.

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Luca Barbieri, Pierfrancesco Di Cintio, Guido Giachetti, Alicia Simon-Petit, Lapo Casetti. 2021-12-20. Symplectic coarse graining approach to the dynamics of spherical self-gravitating systems. https://doi.org/10.1093/mnras%2Fstac477

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