Ion beam profile diagnosis methods for vacuum arc ion source in sealed tube neutron generator

摘要

The ion beam for vacuum arc ion source in sealed tube neutron generator owns some special features, such as multi-particle mixtures, high-intensity beams, short pulse-width, single gap acceleration system and eccentric beams. It is related to the design of the vacuum arc ion source and beam optics, which affect the insulation withstand of the device, the life of tritium target, the neutron yield, and so on. The beam profile is useful information for designing a high intensity sealed tube neutron generator. An improved traditional on-line diagnosis method, which using an aluminum-coated scintillator and a novel off-line diagnosis method, which is based on secondary ion mass spectrometry (SIMS), are introduced, respectively. The methods have high resolution and can provide intensity distribution of ion beam profile and ion composition on-site the neutron generator. The preliminary experimental results indicate the total ion beam profile distribution, the hydrogen distribution and titanium distribution, respectively. The results from the two methods can fit each other well.