Effect of Ion Speed Distribution on the Spectral Shape of the 2.5 MeV Neutron Line Produced by DD Fusion

摘要

Ion mean energy may be determined from Doppler broadening of the 2.5 MeV neutron line in Maxwellian deuterium plasma. Since many plasmas are non-Maxwellian a Monte Carlo simulation has been used to predict the spectral shape produced by a variety of simple speed distributions with mean energies in the range 1 to 100 keV. The results are Gaussian to high order and their width varies as the square root of the mean ion energy. However, the line width varies substantially among different ion speed distributions with the same mean energy. The similarity in shape of these spectra prevent the determination of the speed distribution type from detailed measurements of the neutron spectrum. 24 refs., 4 figs., 2 tabs. (ERA citation 11:025099)