0000000000949956
AUTHOR
James Osborne
Duality violations in τ hadronic spectral moments
Evidence is presented for the necessity of including duality violations in a consistent description of spectral function moments employed in the precision determination of $\alpha_s$ from $\tau$ decay. A physically motivated ansatz for duality violations in the spectral functions enables us to perform fits to spectral moments employing both pinched and unpinched weights. We describe our analysis strategy and provide some preliminary findings. Final numerical results await completion of an ongoing re-determination of the ALEPH covariance matrices incorporating correlations due to the unfolding procedure which are absent from the currently posted versions. To what extent this issue affects ex…
Duality violations in hadronic tau decays and the value of alpha_s
We discuss the quantitative impact of duality violations on the determination of the strong coupling constant from hadronic tau decays, based on a preliminary analysis of OPAL data.