Meson-Meson and Meson-Baryon Interactions in Lattice QCD

TL;DR

This study uses lattice QCD simulations to analyze meson-meson and meson-baryon interactions, revealing weak potentials and marginal effects from quark-exchange diagrams within a specific distance range.

Contribution

It introduces a lattice QCD approach to quantify inter-hadron potentials, highlighting the weak interaction strength and minimal impact of quark-exchange diagrams.

Findings

Both potentials are weak across the studied range.

Quark-exchange diagrams have marginal effects.

Potential measurements are consistent with theoretical expectations.

Abstract

We study the meson-meson and meson-baryon interactions in lattice QCD. The simulation is performed on 20^3 * 24 lattice at \beta=5.7 using Wilson gauge action and Wilson fermion at the quenched level. By adopting one static quark for each hadron as "heavy-light meson" and "heavy-light-light baryon", we define the distance $r$ of two hadrons and extract the inter-hadron potential from the energy difference of the two-particle state and its asymptotic state. We find that both of the meson-meson and meson-baryon potentials are nontrivially weak for the whole range of 0.2 fm <= r <= 0.8 fm. The effect of including/excluding the quark-exchange diagrams is found to be marginal.