Lattice Input on the τ Vus Puzzle

Abstract

|$V_{us}$| values obtained from recent hadronic-τ-decay-based flavor-breaking sum rule analyses are significantly lower than expectations based on 3-family unitarity and results obtained from other sources. We use lattice data to investigate the accuracy/reliability of the OPE representation of the flavor-breaking correlator combination entering these analyses. The behavior of an alternate combination, chosen to reduce problems associated with the slow convergence of the $D=2$ OPE series, and entering an alternate mixed τ-electroproduction sum rule, is also investigated. Preliminary updates of both analyses, predicated on lessons learned from the lattice data, are also presented.