Lower Hybrid Two Stream Instability in Quasi-Neutral Electron Beam

In a quasi-neutral electron beam of hollow cylindrical type the lower hybrid two stream instability is observed. By applying a radial electric field externally, the perpendicular drift velocity u ⊥ is controlled and the enhancement and suppression of the instability are made artificially. Further, the superposition of pulsed radial field shows that the unstable waves grow exponentially and the frequency and growth rate measured as functions of u ⊥ . These observed behaviors are interpreted by the linear theory of the lower hybrid two stream instability. Experimental results show that, after exponentially growing, the amplitude of the instability is saturated is saturated and the ions are heated.