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arXiv · 1508.01021

Nucleon-pion-state contributions in the determination of the nucleon axial charge

Oliver Bar
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Abstract

The nucleon-pion-state contributions to QCD 2- and 3-point functions used in the calculation of the nucleon axial charge are studied in chiral perturbation theory. For sufficiently small quark masses and large volumes the nucleon-pion states are expected to have smaller total energy than the single-particle excited states. To leading order in chiral perturbation theory the results do not depend on low-energy constants associated with the interpolating nucleon fields and apply to local as well as smeared interpolators. The nucleon-pion-state contribution is found to be at the few percent level.

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Oliver Bar. 2015-08-05. Nucleon-pion-state contributions in the determination of the nucleon axial charge. https://arxiv.org/abs/1508.01021

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