An experimental study of strong turbulence driven by an intense relativistic electron beam

An intense relativistic electron beam (IREB) was injected into an un-magnetized axially decaying plasma. Observed were excitation of rapidly oscillating electric fields such that W = ε0<E²>/2nTe > 1 which lasted as long as about 30 times longer than the beam duration, broadening of the distribution of beam electrons about the initial energy, acceleration of plasma electrons, current enhancement and the total microwave power radiated in the frequency range 18–40 GHz. The experimental data are discussed in connection with the strong Langmuir turbulence.