Artigo
In-flight and collisional dissipation as a mechanism to suppress Fermi acceleration in a breathing Lorentz gas
Fecha
2012-06-01Registro en:
Chaos. Melville: Amer Inst Physics, v. 22, n. 2, p. 11, 2012.
1054-1500
10.1063/1.3697392
WOS:000305833900075
WOS000305833900075.pdf
6130644232718610
0000-0001-8224-3329
Autor
Max Planck Inst Phys Komplexer Syst
Univ Erlangen Nurnberg
Univ Maribor
Universidade Estadual Paulista (Unesp)
Resumen
Some dynamical properties for a time dependent Lorentz gas considering both the dissipative and non dissipative dynamics are studied. The model is described by using a four-dimensional nonlinear mapping. For the conservative dynamics, scaling laws are obtained for the behavior of the average velocity for an ensemble of non interacting particles and the unlimited energy growth is confirmed. For the dissipative case, four different kinds of damping forces are considered namely: (i) restitution coefficient which makes the particle experiences a loss of energy upon collisions; and in-flight dissipation given by (ii) F = -eta V-2; (iii) F = -eta V-mu with mu not equal 1 and mu not equal 2 and; (iv) F = -eta V, where eta is the dissipation parameter. Extensive numerical simulations were made and our results confirm that the unlimited energy growth, observed for the conservative dynamics, is suppressed for the dissipative case. The behaviour of the average velocity is described using scaling arguments and classes of universalities are defined. (C) 2012 American Institute of Physics. [http://dx.doi.org/10.1063/1.3697392]