Stability problem in dynamo

It is shown, that the saturated $\alpha$-effect taken from the nonlinear dynamo equations for the thin disk can still produce exponentially growing magnetic field in the case, when this field does not feed back on the $\alpha$. For negative dynamo number (stationary regime) stability is defined by the structure of the spectra of the linear problem for the positive dynamo numbers. Stability condition for the oscillatory solution (positive dynamo number) is also obtained and related to the phase shift of the original magnetic field, which produced saturated $\alpha$ and magnetic field in the kinematic regime. Results can be used for explanation of the similar effect observed in the shell models simulations as well in the 3D dynamo models in the plane layer and sphere

Superfield formulation of the Lagrangian BRST quantization method

Lagragian quantization rules for general gauge theories are proposed on a basis of a superfield formulation of the standard BRST symmetry. Independence of the $S$-matrix on a choice of the gauge is proved. The Ward identities in terms of superfields are derived.Comment: 9 pages, Latex, no figure

Effective Action of Composite Fields for General Gauge Theories in BLT-Covariant Formalism

The gauge dependence of the effective action of composite fields for general gauge theories in the framework of the quantization method by Batalin, Lavrov and Tyutin is studied. The corresponding Ward identities are obtained. The variation of composite fields effective action is found in terms of new set of operators depending on composite field. The theorem of the on-shell gauge fixing independence for the effective action of composite fields in such formalism is proved. brief discussion of gravitational-vector induced interaction for Maxwell theory with composite fields is given.Comment: Typos corrected. Latex fil