Advanced particle acceleration mechanisms from laser solid interactions

In spite of some unfavourable electron heating caused by these small spot-related effects, LS-RPA is still the dominant mechanism. Carbon ions with energy > 70 MeV/nucleon can be expected from a laser system, such as Gemini with an intensity of 2.4 × 10²¹ W/cm² achievable through tightly focusing the beam. Furthermore, the use of a frequency doubling crystal to achieve ultra-high contrast of the laser needed with these nm thin targets has been considered.

The effect of the frequency-doubled laser on carbon ion acceleration has been investigated.<br><br>In the second investigation, the excitation of Surface Plasmons (SP) using a high-intensity laser on a flat foil target without grating coupling has been proposed theoretically. Simulations show that electrons are accelerated efficiently by the longitudinal electric field of the SP along the target surface when the laser is incident at a grazing angle to the target.

Furthermore, an extended investigation of the laser incidence at the edge of the target, parallel to the surface, is carried out. These high-charge and high-energy electrons are used to accelerate protons present in the contaminant layer of the rear edge of the target. Proton beams with narrow energy spread peak at the high energy end of the spectrum are observed in simulations.

A detailed characterisation of these proton beams is presented here.<br>