$^3S_1-{}^3D_1$ coupled channel $\Lambda_c N$ interactions: chiral effective field theory vs. lattice QCD

TL;DR

This paper compares lattice QCD results for $\Lambda_c N$ interactions with chiral effective field theories at different orders, highlighting limitations in describing phase shifts at low energies and questioning the consistency between models.

Contribution

It provides a detailed comparison of lattice QCD phase shifts with both leading and next-to-leading order chiral effective theories for $\Lambda_c N$ interactions.

Findings

Chiral EFT can fit phase shifts up to 5 MeV c.m. energy.

Discrepancies exist between EFT predictions and lattice QCD beyond 5 MeV.

The consistency between EFT and lattice QCD is limited at low energies.

Abstract

We study the lattice QCD $\Lambda_c N$ phase shifts for the $^3S_1-{}^3D_1$ coupled channel using both the leading order covariant chiral effective theory and the next-to-leading order non-relativistic chiral effective field theory. We show that although it is possible to describe simultaneously the $^3S_1$ and $^3D_1$ phase shifts and the inelasticity $\eta_1$, the fitted energy range is pretty small, only up to $E_\mathrm{c.m.}=5$ MeV. This raises concerns regarding the consistency between leading/next-to-leading order chiral effective field theory and the lattice QCD simulations.