Fast-Ion Emission and Resonance Absorption in Laser-Generated Plasma

Abstract
Plasma was generated by focusing a 35-psec, 1.06-μm laser onto Perspex. Ion expansion characteristics were measured relative to laser polarization and incidence angle. Thermal and "fast" ions were always seen. For optimum resonance absorption conditions the thermal ion energy increased, and a second faster-ion group appeared. Comparison with a computer code showed that the faster ions originated from electron accerleration by an intense electrostatic field.