Precision tests of the J/psi from full lattice QCD: mass, leptonic width and radiative decay rate to eta_c

TL;DR

This paper presents high-precision lattice QCD calculations of the J/psi meson's mass, leptonic width, and radiative decay rate to eta_c, providing stringent tests of quantum chromodynamics with few percent accuracy.

Contribution

The study offers the first full lattice QCD calculations of these J/psi properties, achieving percent-level precision and validating QCD predictions against experimental data.

Findings

Mass, leptonic width, and decay rate agree with experimental values within a few percent.

Time-moments of the vector charmonium correlator match experimental results from e+e- data.

Provides rigorous tests of QCD in the charm quark sector.

Abstract

We show results from calculations in full lattice QCD of the mass, leptonic width and radiative decay rate to eta_c of the J/psi meson. These provide few % tests of QCD. Another (1.5%) test comes from comparison of time-moments of the vector charmonium correlator with results derived from the experimental values of R(e+e- to hadrons) in the charm region.