Low lying charmonium states at the physical point

TL;DR

This paper computes mass splittings of low-lying charmonium states using lattice QCD with multiple lattice spacings and quark masses, providing results that are compared to experimental data.

Contribution

It offers a detailed lattice QCD calculation of charmonium mass splittings at the physical point with systematic uncertainties analyzed.

Findings

Results for 1S hyperfine splitting agree with experiment

Calculated 1P-1S splitting matches experimental values

P-wave spin orbit and tensor splittings are consistent with measurements

Abstract

We present results for the mass splittings of low-lying charmonium states from a calculation with Wilson clover valence quarks with the Fermilab interpretation on an asqtad sea. We use five lattice spacings and two values of the light sea quark mass to extrapolate our results to the physical point. Sources of systematic uncertainty in our calculation are discussed and we compare our results for the 1S hyperfine splitting, the 1P-1S splitting and the P-wave spin orbit and tensor splittings to experiment.