Testing semi-local chiral two-nucleon interaction in selected electroweak processes

TL;DR

This paper applies a new semi-local chiral nucleon-nucleon interaction to study electromagnetic and weak processes in light nuclei, achieving results comparable to experimental data with reduced cutoff dependence.

Contribution

It is the first application of the semi-local improved chiral interaction to electroweak processes, demonstrating its accuracy and reduced cutoff sensitivity compared to previous models.

Findings

Results agree well with experimental data.

Reduced cutoff dependence with the new chiral interaction.

Provides estimates of theoretical uncertainties.

Abstract

The recently developed semi-local improved chiral nucleon-nucleon interaction is used for the first time to study several electromagnetic and weak processes at energies below the pion production threshold. Cross sections and selected polarization observables for deuteron photodisintegration, nucleon-deuteron radiative capture, three-body $^3$He photodisintegration as well as capture rates for decays of the muonic $^2$H and $^3$He atoms are calculated. The Lippmann-Schwinger and Faddeev equations in momentum space are solved to obtain nuclear states. The electromagnetic current operator is taken as a single nucleon current supplemented by many-body contributions induced via the Siegert theorem. For muon capture processes the nonrelativistic weak current together with the dominant relativistic corrections is used. Our results compare well with experimental data, demonstrating the same quality as is observed for the semi-phenomenological AV18 potential. Compared to the older version of the chiral potential with a nonlocal regularization, a much smaller cut-off dependence is found for the state-of-art chiral local interaction employed in this paper. Finally, estimates of errors due to the truncation of the chiral expansion are given.