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Two-pion-exchange parity-violating potential and $\vec{n} p \to d γ$

C. H. Hyun·S. Ando·B. Desplanques
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Abstract

We calculate the parity-violating nucleon-nucleon potential in heavy-baryon chiral perturbation theory up to the next-to-next-to-leading order. The one-pion exchange comes in the leading order and the next-to-next-to-leading order consists of two-pion-exchange and the two-nucleon contact terms. In order to investigate the effect of the higher order contributions, we calculate the parity-violating asymmetry in $\vec{n} p \to d γ$ at the threshold. The one-pion dominates the physical observable and the two-pion contribution is about or less than 10% of the one-pion contribution.

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C. H. Hyun, S. Ando, B. Desplanques. 2006-09-07. Two-pion-exchange parity-violating potential and $\vec{n} p \to d γ$. https://doi.org/10.1140/epja%2Fi2006-10426-8

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