ZhETF, Vol. 133,
p. 183 (January 2008)
(English translation - JETP,
Vol. 106, No. 1,
available online at www.springer.com
CONTRIBUTIONS TO THE THEORY OF MAGNETOROTATIONAL INSTABILITY AND WAVES IN A ROTATING PLASMA
Mikhailovskii A.B., Lominadze J.G., Churikov A.P., Tsypin V.S., Erokhin N.N., Erokhin N.S., Konovalov S.V., Pashitskii E.A., Stepanov A.V., Vladimirov S.V., Galvao R.M.O.
Received: April 11, 2007
PACS: 52.35.Bj, 94.30.cq
One-fluid magnetohydrodynamic (MHD) theory of magnetorotational instability (MRI) in an ideal plasma is presented. The theory predicts a possibility of MRI for arbitrary β , where β is the ratio of the plasma pressure to the magnetic field pressure. The kinetic theory of MRI in a collisionless plasma is developed. It is demonstrated that as in the ideal MHD, MRI can occur in such a plasma for arbitrary β . The mechanism of MRI is discussed; it is shown that the instability appears because of a perturbed parallel electric field. The electrodynamic description of MRI is formulated under the assumption that the dispersion relation is expressed in terms of the permittivity tensor; general properties of this tensor are analyzed. It is shown to be separated into the nonrotational and rotational parts. Thereby, a first step for incorporation of MRI into the general theory of plasma instabilities is made. The rotation effects on Alfvén waves are considered.