Speaker
Description
We use a new, more precise, non-strange, inclusive vector
isovector spectral function to determine the strong coupling at the
tau mass scale employing finite energy sum rules. The new spectral
function is obtained from a combination of (i) ALEPH and OPAL results
for the 2 pion and 4 pion tau decay channels, (ii) recent BaBar
results for the tau K Kbar decay distribution, and (iii)
estimates of the contributions from other hadronic tau decay modes
from recent electroproduction data, related using CVC, for subleading
contributions. This new inclusive spectral function is fully data
based and does not rely on Monte Carlo simulated data. Using the
fixed-order perturbation theory (FOPT) prescription, we find for the
strong coupling at the tau mass the value 0.3077(75), which
corresponds to the five-flavor result 0.1171(10) at the Z mass.
Additional experimental input on the dominant 2 pion and 4 pion tau
decay modes would allow for further improvements to the current
analysis.
What is your topic? | Hadronic decays |
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