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arXiv · 0804.0612

Microcanonical quasi-stationarity of long-range interacting systems in contact with a heat bath

Fulvio Baldovin·Pierre-Henri Chavanis·Enzo Orlandini
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Abstract

On the basis of analytical results and molecular dynamics simulations we clarify the nonequilibrium dynamics of a long-range interacting system in contact with a heat bath. For small couplings with the bath, we show that the system can first be trapped in a Vlasov quasi-stationary state, then a microcanonical one follows, and finally canonical equilibrium is reached at the bath temperature. We compare a Langevin mesoscopic thermostat with Hamiltonian reservoirs microscopically coupled with the system and demonstrate the equivalence of the two descriptions. Our identification of the parameters determining the quasi-stationary lifetimes could be exploited to control experimental systems such as the Free Electron Laser, in the presence of external noise or inherent imperfections.

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Fulvio Baldovin, Pierre-Henri Chavanis, Enzo Orlandini. 2009-03-20. Microcanonical quasi-stationarity of long-range interacting systems in contact with a heat bath. https://doi.org/10.1103/physreve.79.011102

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