Experiments on the interaction of heavy ions with dense plasma at GSI-Darmstadt

Abstract

One of the main objectives of the experimental plasma physics activities at the Gesellschaft für Schwerionenforschung (GSI) are the interaction processes of heavy ions with dense ionized matter. Gas-discharge plasma targets were used for energy loss and charge state measurements in a regime of electron density and temperature up to 10 19 cm −3 and 20 eV, respectively. An improved model of the charge exchange processes in fully ionized hydrogen plasma, taking into account multiple excited electronic configurations which subsequently ionize, has removed the discrepancies of previous theoretical descriptions. The energy loss of the ion beam in partially ionized plasmas such as argon was found to agree very well with our simple theoretical model based on the modified Bethe–Bloch theory. A new setup with a 100 J/5 GW Nd–glass laser now provides access to density ranges up to 10 21 cm −3 and temperatures of up to 100 eV. First results of interaction experiments with laser-produced plasma are presented. To fully exploit the experimental possibilities of the new laser-plasma setup both improved charge state detection systems and better plasma diagnostics are indispensable. Present developments and future possibilities in these fields are presented. This paper summarizes the following contributions: • Interaction of heavy-ion beams with laser plasma by C. Stöckl et al. • Energy Loss of Heavy Ions in a laser-produced plasma by M. Roth et al. • Charge state measurements of heavy ions passing a laser produced plasma with high time resolution by W. Süß et al. • Plasma diagnostics for laser-produced plasma by O. Iwase et al. • Future possibilities of plasma diagnostics at GSI by M. Geißel et al.