Ion Beam Profile Diagnostic Methods for Vacuum Arc Ion Source in Sealed-Tube Neutron Generator

Abstract

The pulsed ion beam from a vacuum arc source in a compact sealed-tube neutron generator owns many special features, such as multiparticle mixture beams, high-intensity beams, short pulsewidth beams, transporting in a single gap acceleration system, and eccentric beams. Beam profile and composition are useful information for designing a high-intensity sealed-tube neutron generator, especially for the insulation withstand of the device, the life of the tritium target, the neutron yield, and so on. An improved traditional online diagnostic method that uses an aluminum-coated scintillator screen and a novel offline diagnostic method that is based on secondary ion mass spectrometry are introduced, respectively. The preliminary experimental results can show the intensity distribution of the ion beam profile and the composition with high resolution. The results from the two methods can fit each other well.Index Terms-Beam profile, neutron generator, scintillator screen, secondary ion mass spectrometry (SIMS), vacuum arc ion source.

Numerical study on variable aperture extraction grids of a titanium hydride cathodic vacuum arc ion source

“…Vacuum arc ion sources can produce multiple components and charge state ions without external working gas, which are widely used in surface coating, particle accelerators, ion implanters, etc [1][2][3][4][5]. When the electrodes of the vacuum arc ion source are made of a metallic (usually the titanium) hydride (deuteride), both the desorbed hydrogen (deuterium) and the vaporized metal atom would be ionized, in which the hydrogen (deuterium) ions are extracted for the application of neutron generators [6][7][8]. To improve the neutron yield of neutron generators, high H + /D + ion fraction should be met for the metallic hydride cathodic vacuum arc ion source.…”