Potentials between pairs of static-light mesons

TL;DR

This study investigates the interaction potentials between pairs of static-light mesons in lattice QCD, exploring attraction and repulsion across different channels to understand their relation to exotic charmonium-like states.

Contribution

It provides updated lattice QCD calculations of static-light meson potentials using improved techniques and multiple lattice spacings, focusing on spin and isospin channels relevant to exotic states.

Findings

Identified channels with attractive and repulsive interactions.

Used advanced stochastic propagator techniques for precise measurements.

Analyzed potential behaviors at different lattice spacings.

Abstract

We give an update on our ongoing investigations of potentials between pairs of static-light mesons in Nf=2 Lattice QCD, in different spin and isospin channels. The question of attraction and repulsion is particularly interesting with respect to the X(3872) charmonium state and charged candidates such as the Z+(4430). We employ the nonperturbatively improved Sheikholeslami-Wohlert fermion and the Wilson gauge actions at two lattice spacings a approx. 0.084 fm and a approx. 0.077 fm with a pseudoscalar mass of mPS approx. 770 MeV and mPS approx. 400 MeV respectively. We use stochastic all-to-all propagator techniques, improved by a hopping parameter expansion. The analysis is based on the variational method, utilizing various source and sink interpolators.