TFTR diagnostic neutral beam

A neutral beam has been designed and fabricated to aid in the measurement of ion temperatures of hot, dense tokamak fusion test reactor (TFTR) plasmas. The injected fast neutral atoms offer a twofold benefit: (1) Penetration to the plasma center considerably increases charge exchange neutralization of thermal plasma ions, leading to a localized enhancement of the thermal neutrals efflux into charge exchange neutral analyzers; and (2) charge exchange recombination of fully stripped intrinsic impurity ions, C or O, with fast neutrals allows Doppler broadening and shift measurements of the emitted light to determine both the impurity ion temperature and toroidal rotation with unbalanced beam heating. The design and construction of the beam and those features of the beam unique to its function as a diagnostic tool for TFTR will be presented.