Ion acceleration from golden mylar film irradiated by visible ns pulsed laser

Abstract

A Pulsed ns laser operating at 532 nm wavelength with 150 mJ pulse energy was employed to irradiate micrometric thick mylar films, from 1 to 100 μm thick, covered by 0.05 μm Au in the back face. Protons and light ions have been accelerated by the electric field developed in the non-equilibrium plasma by the laser pulse in a vacuum at an intensity of the order of 10¹⁰ W/cm². Time-of-flight technique, obtained using a Faraday cup and a fast storage oscilloscope, is employed to measure the ion velocity, energy, and yield emitted in backward and forward directions. The yield of the emitted plasma photons is also evaluated. Two ion collectors are used in opposite directions to measure the plasma radiations emitted in backward and forward directions. Data analysis is based on the Coulomb-Boltzmann-shifted (CBS) distribution function. The target ablation yield is evaluated in the order of 3.5 μm per laser shot.