Expressions for the physical structure of a sequence of two zone polytropic stellar models, based on composite analytical solutions of the Lane-Emden equation with indices n = 1 and n = 5, hâve been determined. The coefficients of vibrational stability for radial oscillations of this sequence of models have also been calculated and it is found that increasing the extent of the n = 5 outer zone has a stabilizing effect.

Characteristic frequencies of some modes of radial pulsations and their relative displacements have been determined for a sequence of composite polytropic stellar models having an inner zone of index n = 1 and an envelope n = 5. It is demonstrated that vibrational stability increases with the degree of central condensation of the individual two zone models.

The time dependent multimode equations for magnetoconvection have been solved numerically for a range of parameter values and cell sizes. The solutions demonstrate the nonlinear interactions between the different scales of motion and how the induced magnetic field is concentrated into the smaller length scale. The generation of mean kinetic and magnetic helicity occurs at low Prandtl number which has significant physical interpretations in the solar situation.

A unique data set of 160 MHz solar noise storm positions and polarizations covering a complete sunspot cycle interval from the Skylab period of 1973 through the Solar Maximum intervals of 1980 and 1984 is presented in the form of 27.28-day synoptic plots.