Laser-Driven High-Purity Proton Acceleration Utilizing Hydrogen Clusters −The Creation of GeV Class Ion Beams Close to the Speed of Light−

Abstract

We demonstrate a new scheme using the prominent characteristics of micron-scale hydrogen cluster targets for achieving a level of 0.3 GeV quasi-monoenergetic proton bunch acceleration with low angular divergence by utilizing the internal degree of freedom. In this scheme, the collisionless shock dynamics inside the micron-scale cluster are subsequently coupled with the relativistically induced transparency effect of a high-intensity laser. This step plays an important role. The scheme, which stably works for the finite ranges of parameters with threshold values, is available for experiments.