When a suitable accelerating voltage is applied to extract negative ions from a volume production source, electrons are also extracted. If no means of suppression is utilized, the electron current in a hydrogen plasma would typically be of the order of 80-100 times the negative-ion current. In the accelerator designs in use at Culham Laboratory, el…
The large size of future, and possibly present day, tokamaks requires high neutral atom beam energies for current drive and heating. These injectors must also have a high electrical efficiency and this can be achieved using negative ion sources to create the beam. These large tokamaks, such as ITER or NET require a neutral beam power of around 50-1…
