TTP96-28 Nonfactorizable QCD and Electroweak Corrections to the Hadronic Z Boson Decay Rate

TTP96-28 Nonfactorizable QCD and Electroweak Corrections to the Hadronic Z Boson Decay Rate

TTP96-28 Nonfactorizable QCD and Electroweak Corrections to the Hadronic Z Boson Decay Rate

We present an analysis of two-loop mixed QCD and electroweak corrections to the decay of the Z boson into light quarks. We find that the naive factorization of QCD and electroweak corrections does not describe correctly the two-loop effects. The nonfactorizable corrections shift the width of the Z boson by approximately -0.55(3) MeV and increase the central value of the strong coupling constant determined at LEP by 0.001.

Andrzej Czarnecki and Johann H. K\“uhn
Phys. Rev. Lett. 77 3955-3958 1996
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