Unified chiral analysis of the vector meson spectrum from lattice QCD

TL;DR

This paper develops a unified chiral analysis framework for lattice QCD data to accurately extrapolate the vector meson mass, accounting for lattice artifacts, finite volume effects, and decay channels, achieving results consistent with experimental values.

Contribution

It introduces a comprehensive chiral extrapolation method for vector meson masses from lattice QCD, incorporating finite lattice spacing, volume effects, and decay channels, improving accuracy over polynomial methods.

Findings

Extrapolated M_ ho agrees with experimental data.

Finite lattice spacing and volume effects are well modeled.

Chiral effective field theory extension improves extrapolation accuracy.

Abstract

The chiral extrapolation of the vector meson mass calculated in partially-quenched lattice simulations is investigated. The leading one-loop corrections to the vector meson mass are derived for partially-quenched QCD. A large sample of lattice results from the CP-PACS Collaboration is analysed, with explicit corrections for finite lattice spacing artifacts. To incorporate the effect of the opening decay channel as the chiral limit is approached, the extrapolation is studied using a necessary phenomenological extension of chiral effective field theory. This chiral analysis also provides a quantitative estimate of the leading finite volume corrections. It is found that the discretisation, finite-volume and partial quenching effects can all be very well described in this framework, producing an extrapolated value of M_\rho in excellent agreement with experiment. This procedure is also compared with extrapolations based on polynomial forms, where the results are much less enlightening.