Characteristics of ion emission from plasma produced by high-energy short-wavelength (438 nm) laser radiation

Abstract

Efficient production of highly charged (z>45) high-energy (up to ∼20 MeV) Ta ions by the interaction of a short-wavelength subnanosecond laser pulse with a solid target has been demonstrated by experimental studies of ion emission from plasma generated by the PALS high-energy short-wavelength (3ω0) iodine laser system (⩽0.25 kJ, 0.4 ns, 0.438 μm, ⩽1016 W cm−2) in Prague. The plasma was investigated by means of ion diagnostics based on the time-of-flight method, i.e. ion collectors (ICs) and an electrostatic ion-energy analyser equipped with a windowless electron multiplier serving as an ion current detector. Five ICs were located at different angles with respect to the target normal. The existence of fast highly charged ions, as well as thermal and slow ions, has now been demonstrated for plasma produced by short-wavelength high-energy laser pulses, as it previously was for long-wavelength lasers