| Nucleosynthesis in big-bang and stellar interiors can account for nearly all the elements of the periodic table,and the nuclear reaction rates associated with nucleosynthesis also determine the evolution of the universe.Therefore,the nuclear reaction cross sections of the nuclear astrophysics are required to be measured accurately.At the same time,in the field of practical application,the study of charged nuclear reaction in this energy area can give us a better understanding of the energy generation in the fusion reactor,provide the necessary basic nuclear data for the design of new fusion reactor and nuclear weapon research.In short,both the basic research and the development of the people’s livelihood,this energy area nuclear reaction data are of great significance.The interested energies far below the Coulomb barrier,the cross section(σ(E))drops steeply(nearly exponentially)as energy E decreases.Thus,the direct measurement of σ(E)at the thermonuclear energy becomes almost impossible.The nuclear reaction cross section is usually transformed into an astrophysical S factor that is insensitive to energy change and is extended to the low energy region.For the d-6Li reaction studied in this paper,the study of the astrophysical S factor is not sufficient.There are few problems such as few direct measurement data,the data can not be updated for a long time,the energy is not low enough,and the results of literature reports are quite different.The experimental measurement work was carried out on the low-energy high-current ion beam generator at the Research Center for Electron Photon Science of Tohoku University.Charged-particle spectra for 6Li(d,α)4He,6Li(d,p0)7Li and 6Li(d,p1)7Li*(Ex = 478 ke V)reactions were measured by bombarding concentrated 6Li(6Li: 95 at.%,531 ± 6 K)target with 30-70 ke V deuterium ion beam by 2.5-ke V steps,and the thick target yield of each reaction was obtained.In the data analysis section,combined with the screening potential without the isotope effect,the environmental screening without the exit channel interference,the measured reaction without resonance and other constraints,taking the screening potential and the bare S factor as the adjustable parameters,the least squares method was used to fit the thick target yield of the three reactions and reports of and the corresponding reaction road high energy area reported data at the same time.On the basis of this,the thermonuclear reaction rates for the 6Li(d,α)4He and 6Li(d,p)7Li reactions for temperatures up to 3×109 K was calculated,so as to estimate the abundances of 6Li and 7Li in the solar proton-proton burning process.At the same time,the Oppenheimer-Phillips effect was verified by the ratio of 6Li(d,α)4He and 6Li(d,p)7Li reaction yields.The results show:1.Sbare(0)for 6Li(d,α)4He,6Li(d,p0)7Li and 6Li(d,p1)7Li*(Ex = 478 ke V)reactions are 19.20 ± 0.52,20.46 ± 0.63 and 3.79 ± 0.18 Me V·b,respectively.The functions of the bare S factor for the three reactions are given,and the functions of the S factor for the 6Li(d,p0)7Li and 6Li(d,p1)7Li* reactions are reported for the first time.2.The screening potential of d-6Li reaction in liquid lithium(531 ± 6 K)is 478 ± 42 e V.3.The 6Li(d,α)4He and 6Li(d,p)7Li reactions have almost no effect on 6Li and 7Li abundance.4.There is no Oppenheimer-Phillips effect in the 30-70 ke V energy region. |
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