Laser-Controlled Collective Ion Accelerator

We report first results from a new collective accelerator experiment in which a laser‐controlled channel of ionization is used to control the propagation of the potential well at the front of an intense relativistic electron beam injected at currents above the space‐charge limit. The controlled acceleration of protons at the rate of 40 MeV/m over a distance of 45 cm is reported, in good agreement with experimental design values.