Interaction of monoenergetic electron beam of a high relativistic factor with a dense plasma

Presented are experimental data obtained in an electron linac accelerator with the followina beam parameters: 20 MeV energy, relativistic factor 40, 1A pulse current, 10μs pulse duration; 2.5x10-3 angular divergence, 1cm beam diameter. Beam current and energy spectra of beam electrons without plasma and passing throuah plasma of 5x1015cm-3 density were measured. On passing the beam through plasma registered was X-radiation. X-radiation energy changed in the range from 40 to 90 kV depending on plasma density, and its pulse intensity constituted approximately 105 P/cm2xs. Experimental data have shown that efficiency of collective interactions of monoenergetic beam with small angular divergence increases with the plasma density growth. Anomalous great losses beam energy and electron acceleration are shown to retain with increasing beam energy up to 20 MeV as compared with 2 MeV energy beams. It is noted that in the experiments carried out retained are most conditions necessary for the existence of hydrodynamic stage of beam-plasma interactions