Initial measurement of impurity production and hydrogen energy distribution from neutral beam injectors

Abstract

Impurity production and hydrogen energy distributions for neutral beam injectors (NBI) developed by the plasma Technology Section of Oak Ridge National Laboratory's (ORNL's) Fusion Energy Division have been measured by exposing silicon samples to beam pulses and analyzing them by nuclear microanalysis and secondary ion mass spectrometry (SIMS) techniques. The NBI's have been developed for use on the princeton Large Torus (PLT), the Poloidal Divertor Experiment (PDX), and the Impurity Study Experiment (ISX). Extraction voltages O up to 50 kV are used, and maximum power injected for a 0.5-s pulse is approx. 1.2 MW with a design goal of 1.5 MW. The Medium Energy Test Facility (MRTF) was used for exposure of the single-crystal (100) silicon samples