Hard X-rays and high-current electron beams from X-pinches

Results of experimental studies of the spatial and temporal characteristics of the hard X-rays generated by high-current electron beams in X-pinch experiments on the XP (Cornell University) and BIN (LPI RAS) pulsed power generators are presented. Some issues concerning high-current electron beam transport from the X pinch to the diagnostic system and measurements of the beam current by Faraday cups with different geometries are discussed. Generation of electron beams is an unavoidable property of X-pinches and other pulsed-power-driven pinches of different geometry. Results of computer simulation of electron beam propagation from X-pinch to Faraday cup give the limits of measured current for beams having different energy spread. We emphasize the partially neutralized nature of the beam propagating from the X-pinch to a diagnostic system. Different schemes for beam space-charge neutralization are discussed. Longitudinal neutralization is thought to be the most important method because it enables transport of beams with close to the Alfven current. Experimental and computer simulation results on electron beam generation are compared.