Formation and Propagation of a Proton Ring

Abstract

A magnetically self-confined ring of 430-keV protons with a field reversal on axis of 3% is formed in an 8-kG solenoid, as evidenced by propagation more than 1 m in 15-400 mTorr air or hydrogen without dispersion. Up to 83% of the proton kinetic energy is in rotation and inductive coupling of axial ring energy to azimuthal plasma current induced in air (but not hydrogen) gives reflection of >50% of the ring from a 23% mirror.