EPJ Web of Conferences 118, 01001 (2016)
https://doi.org/10.1051/epjconf/201611801001

The HLS approach to (g − 2)_μ : A Solution to the “τ versus e⁺e⁻” Puzzle

LPNHE des Universitùs Paris VI et Paris VII, IN2P3/CNRS, 4 Place Jussieu, 75252 Paris, France

^a e-mail: benayoun@in2p3.fr
^b e-mail: maurice.benayoun@gmail.com

Published online: 26 April 2016

Abstract

The Hidden Local Symmetry (HLS) Model provides a framework able to encompass several physical processes and gives a unfied description of these in an energy range extending up to the ø mass. Supplied with appropriate symmetry breaking schemes, the HLS Model gives a broken Effective Lagrangian (BHLS). The BHLS Lagrangian gives rise to a fit procedure in which a simultaneous description of the e⁺e⁻ annihilations to π⁺π⁻, π⁰γ, ηγ, π⁺π⁻π⁰, K⁺K⁻, K_LK_S and of the dipion spectrum in the decay τ^±→π^± π⁰v can be performed. Supplemented with a few pieces of information on the ρ⁰ − ω – ø system, the τ dipion spectrum is shown to predict accurately the pion form factor in e⁺e⁻ annihilations. Physics results derived from global fits involving or excluding the τ dipion spectra are found consistent with each others. Therefore, no obvious mismatch between the τ and e⁺e⁻ physics properties arises and the τ − e⁺e⁻ puzzle vanishes within the broken HLS Model.