Charge-exchange and fusion reaction measurements during compression experiments with neutral beam heating in the Tokamak Fusion Test Reactor

Abstract

ABSTRACT. Adiabatic toroidal compression experiments were performed in conjunction with high power neutral beam injection in the Tokamak Fusion Test Reactor (TFTR). Acceleration of beam ions to energies nearly twice the injection energy was measured with a charge exchange neutral particle analyser. Measurements were also made of 2.5 MeV neutrons and 15 MeV protons produced in fusion reactions between the deuterium beam ions and the thermal deuterium and 3 He ions, respectively. When the plasma was compressed, the d (d,n) 3 He fusion reaction rate increased by a factor of five, and the 3 He(d,p)a rate by a factor of twenty. These data were simulated with a bounce averaged Fokker-Planck program, which assumed conservation of angular momentum and magnetic moment during compression. The results indicate that the beam ion acceleration was consistent with adiabatic scaling.

Contemporary Instrumentation and Application of Charge Exchange Neutral Particle Diagnostics in Magnetic Fusion Experiments

“…The energy dynamic range was E max /E min = 30, where E max and E min are the maximum and minimum energies that can be measured simultaneously and the mass rejection between adjacent mass columns was ~ 1000:1. A broad range of ion-related phenomena was investigated such as the ion temperature in Ohmic and neutral beam heated discharges [35], adiabatic toroidal compression experiments [39], fast ion radial diffusion [40], and MHD effects such as fishbones [41]. [42], as illustrated in Fig.…”