Twisted Magnetic Fields in Conducting Fluids

Abstract

The formation of loops in the lines of force of a twisted magnetic field confined within a cylinder of radius R, first suggested by AIfvén (1950a), is discussed by the method of normal modes. The model first becomes unstable with respect to modes which do not lead to the formation of loops. Ignoring this, the condition obtained for loop formation is that the pitch of the twisted field be less than pR.