ENHANCED ENERGY-LOSS OF HEAVY-IONS PASSING A FULLY IONIZED HYDROGEN PLASMA

Experiments are presented that demonstrate the high stopping power of fully ionized hydrogen plasma for low-energy heavy ions. A plasma with electron densities up to 7 . 10(16) cm(-3) at temperatures above 1 eV was created by an electrical discharge. In the described experiment, a stopping power of 1.08 GeV/(mg/cm(2)) was measured using singly char ged krypton ions at 45-keV/u energy. The measured stopping power excee ds the corresponding value in cold hydrogen gas by a factor of 35. The se measurements confirm the theoretical stopping power predictions clo se to the expected maximum in a fully ionized plasma.