LLNL, Livermore, California, USA
The current interest for the next generation linear induction radiography accelerator (LIA) is to generate multiple electron beam pulses with high peak currents. The beam energy and current may vary from pulse to pulse. Conse-quently, the transport and control of multi-pulsing intense electron beams through a focus-ing lattice over a long distance on such machine becomes challenging. Simulation studies of multi-pulse LIAs using AMBER [1] and BREAKUP Code [2] are described. These include optimized focusing magnetic tune for beams with energy and current variations, and steering correction for corkscrew motion. The impact of energy variation and accelerating voltage error on radiograph performance are discussed.
LLNL, Livermore, California, USA
The Flash X-ray Radiography (FXR) [1] line-ar induction accelerator at Lawrence Livermore National Laboratory produces x-ray bursts for radiographs. The machine is able to produce x-ray spot sizes less than 2mm. Using the spot sizes measured from the magnet scanning, the beam parameters are unfolded by modelling the FXR LINAC with the simulation code AMBER [2] and the envelope code XENV [3]. In this study, the most recent spot size measurement results and techniques used to extract the beam parameters are described. Using the unfolded beam parameters as the initial condition, the backstreaming ions' neutralization factor f = 0.3 is found by comparing the calculated spot sizes with measured spot sizes at the target.