Nonadiabatic Motion of a Charged Particle in an Axisymmetric Magnetic Barrier

Abstract

A study was made of the motion of a single charged particle in the magnetic induction generated by an axisymmetric current sheet, the current of which was sinusoidally modulated along the axis. Several adiabatically invariant quantities were investigated, and it was found that M₄ = |v×B|²/|B|³ varied least along a given trajectory. A particle was considered to be adiabatic if M₄ varied by less than 5% during a single interaction with the magnetic barrier. An averaging process was found which made it possible to predict the relations between particle mass and energy, and the magnetic induction strength and geometry, which cause M₄ to vary by more than 5% during a single interaction with the magnetic barrier. Experimental apparatus was constructed which made it possible to study a single interaction of a beam of charged particles with a magnetic barrier under steady‐state conditions. An experimental procedure was developed which made it possible to detect the transition from adiabatic to nonadiabatic reflection of the ion beam, and the results were compared with the results of the numerical computation.