Study On The Technology Of D-T/D-D Neutron Generator

The envelope theory on high-current ion beam transport is investigated. A design on the beam transport line of the neutron generator is presented by simulating D+ beam envelope. The elements of the neutron generator, including ion source, accelerating column, quadruple triplets lens, analytical magnet and HV-supply, are developed and tested. A duoplasmatron ion source is used to produce the D+ beam. The operation of the ion source shows that the life-time of filament is longer than 50h. The electric field distributions of accelerating column are simulated using SUPERFISH code. The simulated results show that the maximum electric field is about 21kV/cm in the accelerating region while the maximum electric field is about 70kV/cm in the shield electrode region. The magnetic field of analytical magnet and quadruple triplets lens are investigated by simulating and measurment. The magnetic field distributions meet the design demand. A 325kV HV-supply driven by an intermediate frequency power supply of 2.5kHz/450V is developed.The associated-particle measurement method is investigated to monitor the D-T/D-D neutron yield. The correction factors for D-T and D-D neutron measurement are respectively calculated for the thick-target and for 135°associated-particle measurement system in the deuterons energy region of 20-600keV. The uncertainty of the calculated factors is less than 2%. An associated-particle measurement system is developed.The neutron generator is assembled. A test in hydrogen ion beam is performed. The beam dots of the mixed hydrogen beam and the proton beam are measured. It is found that the proton beam current has a fluctuation of 4%. Using a titanium-tritium target, D-T reaction neutrons are produced and measured at the D beam energy of 215keV and the D beam current of 1.0mA. Typical associatedαspectrum from 135°associated particle measurement system is presented. D-T neutron yield, derived fromαpure counts, is greater than 109n/s. Using a titanium-film target with molybdenum substrate, an experimental test on the D-D reaction is performed at the deuteron beam of 236keV and 0.5mA. Typical associated proton spectrum from 135°associated particle measurement system is presented. D-D neutron yield, derived from proton pure counts, is greater than 108n/s.