Preliminary lattice study of $I=0$ $K \overline{K}$ scattering

TL;DR

This study uses lattice QCD simulations to investigate the $I=0$ $K ar{K}$ scattering, revealing an attractive interaction consistent with theoretical expectations, and discusses the challenges and improvements in such calculations.

Contribution

First ab initio lattice study of $K ar{K}$ scattering in the $I=0$ channel using improved staggered fermions and advanced techniques for disconnected diagrams.

Findings

Detected attractive $K ar{K}$ interaction in the $I=0$ channel.

Successfully measured four-point functions without gauge fixing.

Discussed methods to improve statistical accuracy in lattice calculations.

Abstract

We deliver the realistic ab initio lattice investigations of $K \overline{K}$ scattering. In the Asqtad-improved staggered dynamical fermion formulation, we carefully measure $K\overline{K}$ four-point function in the $I=0$ channel by moving wall sources without gauge fixing, and clearly find an attractive interaction in this channel, which is in agreement with the theoretical predictions. An essential ingredient in our lattice calculation is to properly treat the disconnected diagram. Moreover, we explain the difficulties of these lattice calculations, and discuss the way to improve the statistics. Our lattice investigations are carried out with the MILC $2+1$ gauge configuration at lattice spacing $a \approx 0.15$~fm.