Renormalization of one-pion exchange in chiral effective field theory for antinucleon-nucleon scattering

Abstract

The renormalization of iterated one-pion exchange (OPE) has been studied in Chiral Effective Field Theory (χEFT) for the antinucleon-nucleon (NN ) scattering in some partial waves (Phys.Rev. C 105, 054005 (2022)). We go further for the other higher partial waves but with total angular momenta J ≤ 3 in this paper. Contact interactions are represented by a complex spherical well in coordinate space. Changing the radius of the spherical well means changing the cutoff. We check the cutoff dependence of the phase shifts, inelasticities, and mixing angles for the partial waves, and show that contact interactions are needed at leading order in channels where the singular tensor potentials of OPE are attractive. Results are compared with the energy-dependent partial-wave analysis of NN scattering data. Comparisons between our conclusions and applications of χEFT to the nucleon-nucleon system are discussed as well.

Lepton- and baryon-number violation in nuclear effective field theory

“…At low momenta, all interactions can be treated in perturbation theory, starting with H 0 = O(4π/m N M NN ) which is then determined in terms of the isospintriplet 3 S 1 scattering length a np 0.44 + i0.96 fm [31]. As Q increases one expects that, like in NN , pions become nonperturbative in the lowest waves together with contact interactions needed for renormalization [32].…”

Renormalization of one-pion exchange in higher partial waves in chiral effective field theory for antinucleon-nucleon system*

“…In Refs. [20,21], Weinberg's proposal was extended to antinucleon-nucleon ( ) systems. Here, we discuss the renormalization of one-pion exchange (OPE) in χEFT for scattering at low energies, which is an extension of Ref.…”