Generation of fast protons by interaction of modest laser intensities with H2O “snow” nano-wire targets

Abstract We report on the generation of protons with energies of 5.5 MeV when irradiating an H 2 O nano-wire layer grown on a sapphire plate with an intensity of 5×10 17  W/cm 2 . A theoretical model is suggested in which plasma near the tip of the wire is subject to enhanced electrical fields and protons are accelerated to several MeVs.