Low-energy nuclear fusion data and their relation to magnetic and laser fusion

Abstract

We investigated the accuracy of the basic fusion data for the T(d,n) 4 He, 3 He(d,p) 4 He, T(t,2n) 4 He, D(d,n) 3 He, and D(d,p)T reactions in the 10-to 100 keV bombarding energy region, and assessed the effects of inaccuracies on the design of fusion reactors. The data base for these reactions | particularly the most critical T(d,n) 4 He reaction] rests on 25-year-old experiments whose accuracy (often assumed to be ±5%) has rarely been questioned: yet in all except the d + d reactions, there are significant differences among data set". The errors in the basic data sets may be considerably larger than previously expected, and the effect on design calculations should be significant. Much of the trouble apparently lies in the accuracy of the energy measurements, which are difficult at low energies. Systemptic erroi s of up to 50% are possible in the reactivity values )f the present Tfd.n^He data base. The error, n. me reactivity will propagate proportionately into the errors in fusion probabilities in reactor calculations. 3 He(d,p) 4 He reaction cross sections could be in error by as much as 50% in the low-energy region. The D(d,n) 3 He and D(d,p)T cross sections appear to be well known and consistent. The T(t,2n) 4 He cross section is poorly known and may be subject to large systematic errors. Improved absolute measurements for all the reactions in the low bombarding energy region