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arXiv · 1209.2552

Near Threshold Proton-Proton Fusion in Effective Field Theory

Jiunn-Wei Chen·C. -P. Liu·Shen-Hsi Yu
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Abstract

The astrophysical S-factor for proton-proton fusion, S_11(E), is obtained with the nuclear matrix element analytically calculated in pionless effective field theory. To the third order, the zero-energy result S_11(0) and the first energy derivative S'_11(0) are found to be (3.99 \pm 0.14)* 10^-25 MeV b and S_11(0)*(11.3 \pm 0.1) MeV^-1, respectively; both consistent with the current adopted values. The second energy derivative is also calculated for the first time, and the result S"_11(0) = S_11(0)*(170 \pm 2) MeV^-2 contributes at the level of 0.5% to the fusion rate at the solar center, which is smaller than 1% as previously estimated.

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Jiunn-Wei Chen, C. -P. Liu, Shen-Hsi Yu. 2012-11-21. Near Threshold Proton-Proton Fusion in Effective Field Theory. https://doi.org/10.1016/j.physletb.2013.02.019

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