Ion acceleration from highly relativistic laser-solid interactions at 400nm

Interactions of ultrafast, high intensity lasers with solid targets present an efficient, high-energy ion source for various applications ranging from laboratory astrophysics to nuclear medicine and inertial confinement fusion. Nearly all laser ion acceleration experiments to date have used light in the near infrared wavelength range. 400nm laser-solid interactions at intensities exceeding 10^21 W/cm^2 were investigated at the ALEPH laser facility. Energy spectra and beam characteristics of accelerated protons were recorded using radiochromic film. Target properties of thickness and conductivity were investigated with the accelerated energy spectrum. Numerical modeling was performed with particle-in-cell methods to better understand the underlying physics.