On the possibility of neutron spectrometry for determination of fuel ion densities in DT plasmas

The fuel density (given by nd+nt and nd/nt) is one of the important parameters to determine and control in burning DT plasmas. Here, we propose that nd and nt be deduced from data on the dd and dt neutron energy distributions to be recorded with a neutron spectrometer having energy selective response to the plasma neutron flux. The potential diagnostic capabilities of the magnetic proton recoil spectrometer system are tested for the measuring conditions to be presented by the next step tokamaks such as ITER.