Source of Negative Hydrogen Ions with Hot Cathode Available to Purchase

In the report an H⁻ ion source with following parameters is described. Ion energy is up to 30 keV, current is up to 5 mA, pulse duration varies from 1 to tens microseconds. H⁻ ions are produced in magnetron discharge near a hot cathode surface made of LaB₆ or IrCe alloy, which is 6 mm in diameter. H⁻ ions are extracted through 0.8×7 mm slot. An electromagnetic valve was used for pulsed gas feed. Ion current depends on discharge current that in turn is defined by cathode temperature, discharge voltage, and hydrogen pressure. Two permanent magnets fixed on iron yoke generate magnetic field for magnetron discharge. There are a magnetic and electrostatic corrections of trajectories of extracted H⁻ ions. The H⁻ ion source has been used as an injector for tandem accelerator with the following proton beam parameters: energy is 1.4 MeV, current is 3mA, and pulse duration is 2 microseconds. Simulation of ion beam trajectories in the source, transport channel, and tandem accelerator shows good correlation with experiments.