Strong coupling at the $\tau$-mass scale from an improved vector isovector spectral function

Diogo Boito, Maarten Golterman, Kim Maltman +3

We perform a precise extraction of the QCD coupling at the $\tau$-mass scale, ${\alpha }_s(m_{\tau })$, from a new vector isovector spectral function which combines ALEPH and OPAL distributions for…