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Nuclear physics input for solar models

Attila Csoto
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Abstract

We discuss microscopic cluster model descriptions of two solar nuclear reactions, Be7(p,gamma)B8 and He3(He3,2p)He4. The low-energy reaction cross section of Be7(p,gamma)B8, which determines the high-energy solar neutrino flux, is constrained by Be7 and B8 observables. Our results show that a small value of the zero-energy cross section is rather unlikely. In He3(He3,2p)He4 we study the effects of a possible virtual state on the cross section. Although, we have found no indication for such a state so far, its existence cannot be ruled out yet. We calculate the He3(He3,2p)He4 and H3(H3,2n)He4 cross sections in a continuum-discretized coupled channel approximation, and find a good general agreement with the data.

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Attila Csoto. 1997-12-08. Nuclear physics input for solar models. https://arxiv.org/abs/nucl-th/9712033

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