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arXiv · 2407.08342

Contact operators in renormalization of attractive singular potentials

Rui Peng·Bingwei Long·Fu-Rong Xu
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Abstract

We discuss renormalization of chiral nuclear forces in the 3P0 channel of N N scattering at next- to-next-to leading order (N2LO) if the one-pion exchange is treated nonperturbatively at leading order. The matrix elements of the subleading contact potentials become nearly dependent of each other for the so-called exceptional ultraviolet momentum cutoff, making it difficult to determine the strengths of those contact potentials from the empirical phase shifts, as reported in Ref. [1]. We argue that this issue can be resolved by adjusting the strategy by which the low-energy constants are deduced from the data, thus making those exceptional cutoffs amenable to chiral effective field theory.

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Rui Peng, Bingwei Long, Fu-Rong Xu. 2024-07-11. Contact operators in renormalization of attractive singular potentials. https://doi.org/10.1103/physrevc.110.054001

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