Measurement and Analysis of Radial Displacement of High Energy ICRF Driven Ions due to MHD MOdes in JET Plasmas

摘要

High energy neutral particle analyzer(NPA)[1] measurements have been used in JET for determination of distribution function of MeV energy ICRF driven hydrogen isotope[2,3,4,5] and He-3 ions[6]. Measurements of distribution of confined DT fusion #alpha#-particles[7], and knock-on ions produced by close elastic collisions between DT fusion #alpha#-particles and thermal plasma fuel ions[7,8] have also been made. These measurements rely on impurity induced neutralization(IIN)[2], in which non-perturbing neutralization of the energetic ions is effected by one- and two-electron species of the main intrinsic plasma impurities, carbon, beryllium and helium. through these experiments the physical basis of the measurement has become quantitatively well established, and the method has subsequently been applied also in JT-60U[9] and TFTR[10]. Expulsion of ICRF driven MeV energy ions from the plasma core in JET was deduced from measurements usign the high energy NPA described above.