Ion Acceleration in Strong Electromagnetic Interactions with Plasmas

Abstract

Energetic ions of energy up to $7k{T}_{e}$ are detected when an inhomogeneous plasma ($\frac{{T}_{e}}{{T}_{i}}\ensuremath{\cong}10$) is irradiated by microwave pulses ($\frac{{{E}_{0}}^{2}}{4\ensuremath{\pi}\mathrm{nk}{T}_{e}}\ensuremath{\approx}{10}^{\ensuremath{-}2}$) of short durations ($\ensuremath{\tau}$ approximately twice the ion-plasma period). Time- and space-resolved analyses trace their origin to the generation of density cavitons by ponderomotive forces. The axially directed energetic-ion flux carries a significant fraction of incident electromagnetic energy.