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arXiv · 2505.02034

Chiral $3\pi$-exchange potential using the method of unitary transformation

Victor Springer·Hermann Krebs·Evgeny Epelbaum
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Abstract

Nuclear potentials are known to exhibit a considerable degree of scheme dependence. For one- and two-pion exchange nucleon-nucleon (NN) potentials, unitary ambiguities start showing up at the level of the leading relativistic corrections to the dominant static contributions. However, for the three-pion exchange potential, scheme-dependent contributions are expected to appear already at the static level. Here, we analyze the leading and subleading chiral $3\pi$-exchange NN potentials using the method of unitary transformation. In line with the expectations, our results for selected classes of contributions differ from those obtained by Kaiser using S-matrix matching. We present analytical expressions for the $3\pi$-exchange potential, which are off-shell consistent with the interactions used by the Bochum group, and discuss the numerical importance of the observed differences.

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Victor Springer, Hermann Krebs, Evgeny Epelbaum. 2025-05-04. Chiral $3\pi$-exchange potential using the method of unitary transformation. https://arxiv.org/abs/2505.02034

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