A Combination of Permanent Magnet and Magnetic Coil for a Large Diameter Ion Source

摘要

A large diameter ion source for fast neutral beam injection is designed under a magnetic field composed of a circular ferrite permanent magnet and a usual coreless magnetic coil. As the magnetic field is reduced abruptly in a discharge anode, an ion source with a uniform ion current density over a large diameter is produced easily without a 'button' of ORNL duoPIGatron type ion source (a floating electrode to diffuse an axial plasma flow radially).