Proton Acceleration in Plasma Waves Produced by Backward Raman Scattering

This paper proposes a new method of proton acceleration. A slow plasma wave produced by backward Raman scattering captures slow protons injected. A density gradient of a plasma enables the wave phase velocity to increase as the proton test beams are accelerated. A proof-of-principle experiment is proposed using a T laser and test beams from a Van de Graaff accelerator, in which a 500mJ laser will give acceleration gain of ∼ 50MeV in a distance of 500μm.