Experiments on the excitation of large amplitude plasma waves for ultra-relativistic particle acceleration

The generation of high phase-velocity, large-amplitude plasma-wave using plasmas and either electron beams or lasers is of fundamental interest for the field of particle accelerator physics. A review is made over the recently performed experiments: electron wake-field at Argone National Laboratory, laser beat-wave with CO2 lasers at I.N.R.S. and U.C.L.A., and with Nd-glass laser at Ecole Polytechnique. With both lasers, electric fields of the order of 1 GV/m have been detected. At U.C.L.A., injected electrons have been accelerated from 1.5 MeV to 10 MeV by the CO2 excited beat wave showing therefore the efficiency of the physical process. Promising photon wake-field experiments are also in preparation. (orig.)