Measurements of fast-ion losses due to the ‘fishbone’ instability during high-βTq neutral-beam-heated discharges in the Poloidal Divertor Experiment have been made using two new vertical-viewing charge-exchange analysers. The measurements show that the instability has an n = 1 toroidal mode number, and that it ejects beam ions in a toroidally rotating bacon directed outward along a major radius. Observations of ejected ions with energies up to twice the beam injection energy at R ≈ Ro + a indicate the presence of a non-µ-conserving acceleration mechanism.
All Science Journal Classification (ASJC) codes
- Nuclear and High Energy Physics
- Condensed Matter Physics