Nuclear Reactions among the Hydrogen Isotopes at Low Energies

The low-energy fusion cross-section (LEFCS) apparatus installed at the Los Alamos Van de Graaff facility has been used to measure the cross sections for the important fusion-energy reaction D(t, α)n over the triton bombarding energy range of 12.5 to 117 keV. This corresponds to an equivalent deuteron bombarding energy range of 8.3 to 78.1 keV and to a D+T plasma temperature (kT) range of 0.7 to 18.8 keV. Over most of the energy range the cross sections are accurate to 1.4%, with the error rising to 4.8% at the lowest energy. A data base was constructed for deuteron bombarding energies up to about 250 keV that included our data and four other data sets. This data base can be fitted quite well with a single-level (3/2+) resonance formula in the R-matrix formalism. Work is currently in progress on the D(d, p) T and D(d, He) n reactions, with studies of D(t, γ) and T(t, α)nn planned for the future.