Pade approximants and g-2 for the muon

TL;DR

This paper introduces a model-independent method using Pade approximants to extrapolate the hadronic vacuum polarization in lattice QCD calculations of the muon g-2, reducing model dependence and improving accuracy.

Contribution

The paper presents a novel, model-independent extrapolation technique based on Pade approximants for the hadronic vacuum polarization in muon g-2 calculations.

Findings

Initial tests show improved extrapolation accuracy.

Reduces reliance on vector meson dominance models.

Potential for more precise muon g-2 estimates.

Abstract

The leading hadronic contribution to the muon anomalous magnetic moment is given by a weighted euclidean momentum integral of the hadronic vacuum polarization. This integral is dominated by momenta of order the muon mass. Since in lattice QCD it is difficult to compute the vacuum polarization at a large number of low momenta, a parametrization of the vacuum polarization is required to extrapolate the data. Most fits to date are based on vector meson dominance, which introduces model dependence into the lattice computation of the magnetic moment. Here we introduce a model-independent extrapolation method, and present a few first tests of this new method.