1209.2552 (Jiunn-Wei Chen et al.)

Near Threshold Proton-Proton Fusion in Effective Field Theory    [PDF]

Jiunn-Wei Chen, C. -P. Liu, Shen-Hsi Yu

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 only contributes at the level of 0.05% to the fusion rate at the solar center, which is smaller than 1% as previously estimated.

View original: http://arxiv.org/abs/1209.2552