Chiral -exchange potential using the method of unitary transformation
Phys. Rev. C 112, 034004 – Published 25 September, 2025
DOI: https://doi.org/10.1103/tr4h-nl4d
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 -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 -matrix matching. We present analytical expressions for the -exchange potential, which are off-shell consistent with the interactions used by the Bochum group, and discuss the numerical importance of the observed differences.