Charmonium spectroscopy and mixing with light quark and open charm states from nF=2 lattice QCD

TL;DR

This study uses nF=2 lattice QCD to analyze the charmonium spectrum, including higher states and mixing with light and open charm mesons, providing insights into their interactions and upper limits on mixing amplitudes.

Contribution

It presents a detailed lattice QCD analysis of charmonium states, including mixing effects with light and open charm mesons, using advanced computational techniques.

Findings

Upper limit on eta_c mixing with light pseudoscalar mesons

Investigation of charmonium mixing near open charm thresholds

Application of variational technique and improved propagators

Abstract

We study the charmonium spectrum including higher spin and gluonic excitations. We determine an upper limit on the mixing of the eta_c ground state with light pseudoscalar flavour-singlet mesons and investigate the mixing of charmonia near open charm thresholds with pairs of (excited) D and anti-D mesons. For charm and light valence quarks and nF=2 sea quarks, we employ the non-perturbatively improved Sheikholeslami-Wohlert (clover) action. Excited states are accessed using the variational technique, starting from a basis of suitably optimised operators. For some aspects of this study, the use of improved stochastic all-to-all propagators was essential.