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arXiv · 1312.1614

Velocity filtration and temperature inversion in a system with long-range interactions

Lapo Casetti·Shamik Gupta
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Abstract

Temperature inversion due to velocity filtration, a mechanism originally proposed to explain the heating of the solar corona, is demonstrated to occur also in a simple paradigmatic model with long-range interactions, the Hamiltonian mean-field model. Using molecular dynamics simulations, we show that when the system settles into an inhomogeneous quasi-stationary state in which the velocity distribution has suprathermal tails, the temperature and density profiles are anticorrelated: denser parts of the system are colder than dilute ones. We argue that this may be a generic property of long-range interacting systems.

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Lapo Casetti, Shamik Gupta. 2014-04-11. Velocity filtration and temperature inversion in a system with long-range interactions. https://doi.org/10.1140/epjb%2Fe2014-50136-y

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