ON THE t(d, n)α REACTIVITY IN FUSION REACTORS

We argue that the most accurate t(d, n)α cross section data obtained by the Los Alamos group are enhanced at energies smaller than E_cm≈16 keV due to screening effects caused by the electrons present in the target. We show that these data in the energy range E_cm=16–70 keV can be well reproduced by a single Breit-Wigner resonance formula which, however, disagrees with the data at lower energies. Consistently the observed deviations can be associated with electron screening effects where the latter are estimated within the Thomas-Fermi model or a static Hartree-Fock approach. Adopting the present Breit-Wigner fit to the data at E_cm≥16 keV, we have calculated the reactivity of a d+t plasma at thermal equilibrium in the temperature range kT<10 keV as it might be important for future fusion reactors.