Five-Loop Running of the QCD Coupling Constant
Five-Loop Running of the QCD Coupling Constant
We analytically compute the five-loop term in the beta function which governs the running of α_{s}-the quark-gluon coupling constant in QCD. The new term leads to a reduction of the theory uncertainty in α_{s} taken at the Z-boson scale as extracted from the τ-lepton decays as well as to new, …