a1 Neutron Physics Division, Bhabha Atomic Research Centre, Bombay-400 085, India
a2 Laser and Plasma Technology Division, Bhabha Atomic Research Centre, Bombay-400085, India
During propagation of a relativistic electron beam in hydrogen gas at sub-torr pressures using a foil-less diode, low-frequency oscillations in the megahertz range are observed in the net current wave forms, and continue even after passage of the beam. The novel feature of the experiment is that both beam generation and propagation take place in the same low-pressure regime, and hence the beam parameters are functions of gas pressures. Analysis of the experimental results shows that the low-frequency oscillations result from the resistive-hose instability.
(Received September 14 1990)
(Revised May 07 1991)