The spherically symmetric α2-dynamo and some of its spectral peculiarities


The spherically symmetric α2-dynamo and some of its spectral peculiarities

Günther, U.; Kirillov, O.; Samsonov, B.; Stefani, F.

A brief overview is given over recent results on the spectral properties of spherically symmetric MHD α2-dynamos. In particular, the spectra of sphere-confined fluid or plasma configurations with physically realistic boundary conditions (BCs) (surrounding vacuum) and with idealized BCs (super-conducting surrounding) are discussed. The subjects comprise third-order branch points of the spectrum, self-adjointness of the dynamo operator in a Krein space as well as the resonant unfolding of diabolical points. It is sketched how certain classes of dynamos with a strongly localized α-profile embedded in a conducting surrounding can be mode decoupled by a diagonalization of the dynamo operator matrix. A mapping of the dynamo eigenvalue problem to that of a quantum mechanical Hamiltonian with energy dependent potential is used to obtain qualitative information about the spectral behavior. Links to supersymmetric Quantum Mechanics and to the Dirac equation are indicated.

Keywords: MHD dynamo; operator theory; spectrum; Krein space; boundary conditions; third-order branch points; Jordan structures; diabolical points; resonance; Korteveg-de Vries equation; supersymmetry; Quantum Mechanics; Dirac equation

  • Open Access Logo Acta Polytechnica 47(2007)2-3, 75-81
    ISSN: 1210-2709

Permalink: https://www.hzdr.de/publications/Publ-9573