Abstract Since the original work by [Sir Geoffrey Ingram] Taylor several authors have reported theoretical and experimental calculations on Rayleigh-Taylor and other gravitational instabilities for various fluid and field geometries of magnetohydrodynamical interest. In the particular case of the theta pinch geometry, a Rayleigh-Taylor instability is found to occur in the first (adiabatic) expansion stage of the columns, with experimental growth rates of the proper order of magnitude for this type...

Abstract The gravitational instabilities of a system consisting of two homogenous fluids in concentric cylindrical configuration (theta-pinch), in the presence of a uniform axial magnetic field, are investigated. The fluids are assumed to be incompressible, and viscous, with infinite conductivity. The dispersion relation is developed by two methods. In the first, an exact determination is made based upon the time development of an infinitesimal disturbance of the equilibrium conditions. In the...