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Constraints on proton-proton fusion from helioseismology

K. I. T. Brown·M. N. Butler·D. B. Guenther
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Abstract

The proton-proton ($pp$) fusion cross-section found at the heart of solar models is unconstrained experimentally and relies solely on theoretical calculations. Effective field theory provides an opportunity to constrain the $pp$ cross-section experimentally, however, this method is complicated by the appearance of two-nucleon effects in the form of an unknown parameter $L_{1,A}$. We present a method to constrain $L_{1,A}$ using the Standard Solar Model and helioseismology. Using this method, we determine a value of $L_{1,A}$ = 7.0 fm$^{3}$ with a range of 1.6 to 12.4 fm$^{3}$. These results are consistent with theoretical estimates of $L_{1,A} \approx$ 6 fm$^{3}$.

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K. I. T. Brown, M. N. Butler, D. B. Guenther. 2002-07-03. Constraints on proton-proton fusion from helioseismology. https://arxiv.org/abs/nucl-th/0207008

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