A generic feature of systems with long-range interactions is the presence of quasistationary states with non-Gaussian single particle velocity distributions. For the case of the Hamiltonian mean-field model, we demonstrate that a maximum entropy principle applied to the associated Vlasov equation explains known features of such states for a wide range of initial conditions. We are able to reproduce velocity distribution functions with an analytic expression which is derived from the theory with no adjustable parameters. A normal diffusion of angles is detected, which is consistent with Gaussian tails of velocity distributions. A dynamical effect, two oscillating clusters surrounded by a halo, is also found and theoretically justified.
|Titolo:||Maximum entropy principle explains quasistationary states in systems with long-range interactions: The example of the Hamiltonian mean-field model|
|Autori:||A. Antoniazzi; D. Fanelli; J. Barre; P. H. Chavanis; T. Dauxois; S. Ruffo|
|Rivista:||PHYSICAL REVIEW. E, STATISTICAL, NONLINEAR AND SOFT MATTER PHYSICS|
|Data di pubblicazione:||2007|
|Digital Object Identifier (DOI):||10.1103/PhysRevE.75.011112|
|Appare nelle tipologie:||1.1 Journal article|