Transport and stability of long-pulse, high-current electron beams in ion focused regime plasma channels for advanced accelerators

Data are presented demonstrating efficient transport (up to 76% instantaneous current transport) of long-pulse high-current electron beams in preformed plasma channels. Channels were created by low-energy electron beam ionization of monatomic gases. These transport efficiencies are comparable to optimum values obtained in previous long-pulse electron beam transport experiments in laser-preionized DEA (diethylaniline). Experimental results show the development of both ion hose instability and microwave emission indicative of REB (relative electron beam) plasma electron two-stream instability. Significant microwave emission was observed in the S-band (2.1-4.3 GHz) only when the neutralization fraction exceeded unity