DMCA
The α Dynamo Effects in Laboratory Plasmas (2001)
| Citations: | 1 - 0 self |
BibTeX
@MISC{Ji01theα,
author = {Hantao Ji and Stewart C. Prager},
title = {The α Dynamo Effects in Laboratory Plasmas},
year = {2001}
}
Share
 |
 |
 |
 |
||
OpenURL
Abstract
A concise review of observations of the α dynamo effect in laboratory plasmas is given. Unlike many astrophysical systems, the laboratory pinch plasmas are driven magnetically. When the system is overdriven, the resultant instabilities cause magnetic and flow fields to fluctuate, and their correlation induces electromotive forces along the mean magnetic field. This α-effect drives mean parallel electric current, which, in turn, modifies the initial background mean magnetic structure towards the stable regime. This drive-andrelax cycle, or the so-called self-organization process, happens in magnetized plasmas in a time scale much shorter than resistive diffusion time, thus it is a fast and unquenched dynamo process. The observed α-effect redistributes magnetic helicity (a measure of twistedness and knottedness of magnetic field lines) but conserves its total value. It can be shown that fast and unquenched dynamos are natural consequences of a driven system where fluctuations are statistically either not stationary in time or not homogeneous in space, or both. Implications to astrophysical phenomena will be discussed. 1. Introduction Phenomena
Keyphrases
dynamo effect laboratory plasma resultant instability astrophysical phenomenon mean magnetic field so-called self-organization process introduction phenomenon initial background mean magnetic structure many astrophysical system resistive diffusion time magnetic helicity unquenched dynamo flow field stable regime unquenched dynamo process driven system concise review time scale magnetic field line observed effect laboratory pinch plasma correlation induces electromotive force drive-andrelax cycle magnetized plasma natural consequence total value
