BHLS$_2$, a New Breaking of the HLS Model and its Phenomenology

Previous studies have shown that the Hidden Local Symmetry (HLS) Model, supplied with appropriate symmetry breaking, provides an Effective Lagrangian (BHLS) able to encompass a large number of processes within a unified framework. A global fit procedure provides a simultaneous description of the e+e− annihilation into 6 final states (π+π−, π0γ, ηγ, π+π−π0, K+K−, KLKS), the dipion spectrum in the τ decay and other light meson partial widths. Additional breaking schemes are defined which extend its scope so as to absorb spacelike processes within a new framework (BHLS2). The phenomenology previously explored with BHLS is revisited in the BHLS2 context with emphasis on the Φ mass region. It is shown that BHLS2 addresses the close spacelike region covered by NA7 and Fermilab data; it is also shown that recent Lattice QCD pion form factor information is accurately predicted by BHLS2 using fits to annihilation data only. The contribution to aμ of these channels over the range of validity of BHLS2 is shown to strongly reduce the former BHLS systematics. The uncertainty on athμ(s√