Ion beam-dense plasma interaction of ICF interest

Abstract

Heavy-ion-dense-plasma interactions of interest in inertial confinement fusion (ICF) have been reviewed. Scaling laws show that within a Born-RPA approximation, the most excited target electrons exhibit the largest stopping capabilities. Thus, standard plasma discharges, fully ionized and conveniently placed on existing acceleration beam lines, behave as efficient benchmarks for testing the basic features of the ion-plasma interaction. The various experimental programs, together with the latest theoretical developments, have been examined. By coupling a hydrogen plasma to a tandem accelerator, transmission and energy losses of 2 MeV/u carbon and sulfur beams passing through a plasma target have been investigated. Fluctuations in beam transmission have been observed and attributed to a plasma lens effect. Energy loss measurements indicate an enhanced stopping power of the plasma relative to its cold matter equivalent. An enhanced energy loss of 333 MeV /sup 233/U ions in a hydrogen discharge plasma with a high degree of ionization has also been observed. The ion stopping in a plasma environment exceeds the stopping in cold matter by more than a factor of two. Measured stopping powers are in agreement with theoretical predictions for the energy loss of heavy ions in a hydrogen plasma.<>