Publications Details
Characterization of electron flow in positive-polarity linear-induction accelerators
Experiments at Sandia National Laboratories have studied the operation of the linear-induction accelerators, HELIA and Hermes 3, in positive polarity. These experiments have provided a unique opportunity to explore the consequences of multiple-cathode electron emission in magnetically insulated transmission lines. An examination of the total energy-canonical momentum distribution of the electrons explains the features of the magnetically insulated flow exhibited by these systems. Simple analysis based on the basic concept of pressure balance, in conjunction with particle-in-cell numerical simulations, shows how the line voltage is related to the anode and cathode currents. Two flow designations are introduced that can apply to multiple-cathode magnetically insulated transmission lines: full-gap flow (FGF), and locally emitted flow (LEF). 16 refs., 15 figs.