ISSN:
1089-7623
Source:
AIP Digital Archive
Topics:
Physics
,
Electrical Engineering, Measurement and Control Technology
Notes:
We propose a new method of measuring the fast confined α-particle distribution in a reacting plasma. The presence of α particles in a D-T plasma will create a high-energy tail on the deuterium and tritium ion energy distributions. A 3.5 MeV alpha can transfer 3.4 MeV to a tritium ion in a single elastic scattering interaction. Calculations of the size of these knock-on tails in tokamaks such as TFTR, JET, and ITER show that it may be possible to measure these tails and provide information on the fast confined alphas. The knock-on tail ions will produce D-T neutrons with energies up to 20.7 MeV, so that D-T neutron spectroscopy can be used to monitor the alpha population. Neutron spectroscopy looks especially attractive for ITER. A collimated array of threshold neutron activation detectors could be used to deduce the confined alpha density profile. Tests of this diagnostic can also be done on TFTR and JET. Existing high-energy neutral particle analyzers may allow observation of the ion tails directly via passive and/or active charge exchange. © 1995 American Institute of Physics.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1063/1.1146217
