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arXiv · 1309.4711

Parity violation in proton-proton scattering from chiral effective field theory

Abstract

We present a calculation of the parity-violating longitudinal asymmetry in proton-proton scattering. The calculation is performed in the framework of chiral effective field theory which is applied systematically to both the parity-conserving and parity-violating interactions. The asymmetry is calculated up to next-to-leading order in the parity-odd nucleon-nucleon potential. At this order the asymmetry depends on two parity-violating low-energy constants: the weak pion-nucleon coupling constant $h_π$ and one four-nucleon contact coupling. By comparison with the existing data, we obtain a rather large range for $h_π= (1.1\pm 2)\cdot 10^{-6}$. This range is consistent with theoretical estimations and experimental limits, but more data are needed to pin down a better constrained value. We conclude that an additional measurement of the asymmetry around 125 MeV lab energy would be beneficial to achieve this goal.

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BibTeXRIS

J. de Vries, Ulf-G. Meißner, E. Epelbaum, N. Kaiser. 2013-11-27. Parity violation in proton-proton scattering from chiral effective field theory. https://doi.org/10.1140/epja%2Fi2013-13149-9

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