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arXiv · 1112.2011

Astrophysical S-factors of proton radiative capture for thermonuclear reactions

Abstract

In this review we have considered the possibility to describe the astrophysical S-factors of radiative capture reactions with light atomic nuclei on the basis of the potential two-cluster model by taking into account the splitting the orbital states according to Young's schemes. Within this model, interaction of the nucleon clusters is described by local two-particle potential determined by fit to the scattering data and properties of bound states of these clusters. Many-body character of the problem is taken into account under some approximation, in terms of the allowed or forbidden by the Pauli principle states in intercluster potentials. An important feature of the approach is accounting for a dependence of interaction potential between clusters on the orbital Young scheme, which determines the permutation symmetry of the nucleon system. The astrophysical S-factors of the radiative capture processes in the p2H, p7Li and p12C systems are analyzed on the basis of this approach. It is shown that the approach allows one to describe quite reasonably experimental data available at low energies, when the phase shifts of cluster-cluster scattering are extracted from the data with minimal errors. In this connection the problem of experimental error decrease is exclusively urgent for the differential cross-sections of elastic scattering of light atomic nuclei at astrophysical energies and to perform a more accurate phase shift analysis. The increase in the accuracy will allow, in future, making more definite conclusions regarding the mechanisms and conditions of thermonuclear reactions, as well as understanding better their nature in general.

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BibTeXRIS

S. B. Dubovichenko, A. V. Dzhazairov-Kakhramanov. 2011-12-09. Astrophysical S-factors of proton radiative capture for thermonuclear reactions. https://arxiv.org/abs/1112.2011

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