Dynamo action in a reversed field pinch

A turbulent dynamo which is the generation of the electromotive force epsilon induced by quasilinear effect of magnetic field fluctuations B and fluid velocity fluctuations V, epsilon = , is expected to play an important role in reversed field pinches. The effective electromotive force consists of two terms, the α-effect (generation of electromotive force) and β-effect (anomalous resistivity). In the case of isotropic turbulence, it is described in terms of the steady magnetic field B, and the α and β coefficients in the form epsilon = αB - β x B. In this paper, the authors study how the turbulent dynamo and steady fluid flow U contribute to the generation of magnetic field, mode structure, and the relaxation of plasmas, assuming the α and β coefficients, and steady fluid velocity U are given. We first consider the normal mode B = B /sub pk/ exp(pt + iKx) in the Cartesian coordinate, and derive a dispersion relation from the induction equation with the electromotive force epsilon induced by the α and β effects: /sup B/ /sub t/ + (Ux)B = (Bx)U + α x B + lambda2B