Tau Data-Based Evaluations of the hadronic vacuum polarization contribution to the muon $g-2$

TL;DR

This paper reviews tau data-driven methods for calculating the hadronic vacuum polarization contribution to muon g-2, highlighting their agreement with lattice results and the need to resolve discrepancies with e+e- data before the upcoming FNAL measurement.

Contribution

It provides a comprehensive review of tau data-driven evaluations of the hadronic vacuum polarization contribution to muon g-2, emphasizing their consistency with lattice results and the implications for new physics.

Findings

Tau data-driven evaluations agree with lattice results.

Discrepancies remain between tau and e+e- data-driven methods.

Resolving these differences is crucial before the FNAL muon g-2 update.

Abstract

We review the tau data-driven computation of Euclidean windows for the hadronic vacuum polarization contribution to the muon anomalous magnetic moment (a_mu), which agree with the lattice results, making the difference of the $e^+e^-$ data-driven methods with them more intriguing. This conundrum needs to be solved by next year, when the final FNAL a_mu measurement will be published, in order to extract firm conclusions on possible new physics effects.