Influence of a biased beam dump on H− beam neutralization measurements with a four-grid energy analyzer

1 January 1990

journal article
research article
Published by AIP Publishing in Review of Scientific Instruments

Vol. 61 (1) , 616-618
https://doi.org/10.1063/1.1141935

Abstract

A four‐grid energy analyzer diagnostic has been developed for the study of H⁻ beam space‐charge compensation, and first measurements have been reported previously. Biased beam‐dump measurements were undertaken to clarify the origin of electron currents measured in the FGA because they far exceeded predictions based on H⁻‐beam ionization and stripping processes. This experiment partially explains the anomalously large radial electron current. The FGA observations for negative beam‐dump bias suggest electron ionization of the background gas is an additional mechanism for producing positive ions.

Keywords

This publication has 2 references indexed in Scilit:

A critical study of emittance measurements of intense low-energy proton beams
Nuclear Instruments and Methods, 1972
Studies of Space Charge Neutralisation in Intense 500 keV Proton Beams
IEEE Transactions on Nuclear Science, 1971