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Title: Chaoticity threshold in magnetized plasmas: Numerical results in the weak coupling regime

The present paper is a numerical counterpart to the theoretical work [Carati et al., Chaos 22, 033124 (2012)]. We are concerned with the transition from order to chaos in a one-component plasma (a system of point electrons with mutual Coulomb interactions, in a uniform neutralizing background), the plasma being immersed in a uniform stationary magnetic field. In the paper [Carati et al., Chaos 22, 033124 (2012)], it was predicted that a transition should take place when the electron density is increased or the field decreased in such a way that the ratio ω{sub p}/ω{sub c} between plasma and cyclotron frequencies becomes of order 1, irrespective of the value of the so-called Coulomb coupling parameter Γ. Here, we perform numerical computations for a first principles model of N point electrons in a periodic box, with mutual Coulomb interactions, using as a probe for chaoticity the time-autocorrelation function of magnetization. We consider two values of Γ (0.04 and 0.016) in the weak coupling regime Γ ≪ 1, with N up to 512. A transition is found to occur for ω{sub p}/ω{sub c} in the range between 0.25 and 2, in fairly good agreement with the theoretical prediction. These results might be of interest formore » the problem of the breakdown of plasma confinement in fusion machines.« less
Authors:
; ; ;  [1] ;  [2]
  1. Università degli Studi di Milano, Milano (Italy)
  2. Consorzio RFX, Associazione EURATOM-ENEA sulla Fusione, Padova (Italy)
Publication Date:
OSTI Identifier:
22251019
Resource Type:
Journal Article
Resource Relation:
Journal Name: Chaos (Woodbury, N. Y.); Journal Volume: 24; Journal Issue: 1; Other Information: (c) 2014 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
70 PLASMA PHYSICS AND FUSION TECHNOLOGY; CALCULATION METHODS; CHAOS THEORY; CYCLOTRON FREQUENCY; ELECTRON DENSITY; ELECTRONS; MAGNETIC FIELDS; MAGNETIZATION; PLASMA; PLASMA CONFINEMENT