Determination of the deuterium temperature profile in magnetic fusion plasmas

Abstract

A new experimental method for determining the radial deuterium temperature profileTD(R) in axisymmetrical toroidal fusion plasmas is presented. The method is based on a generalized Abel inversion of neutron brightness data providing the radial neutron emissivity profile of the plasma. This profile, combined with information on the deuterium density profile, is used to determineTD(R) under the assumption that the ion velocity distribution is Maxwellian. Results are presented here from the analysis of JET data. It is found that, for typical JET plasma conditions, the dominant source of uncertainty arises from the high plasma impurity level and the fact that it is poorly known; these problems can be expected to be remedied and neutron brightness measurements would be expected to be very effective (especially in high-density plasmas) as aTD(R) diagnostics.