Top Quark Contribution to Hadronic Decays of the Z-Boson at Alpha_s^2 in QCD

Abstract

We evaluate the effect of a virtual top quark on the coefficient of ${\alpha }_s^2$ in the decay rates $\Gamma (Z\to \mathrm{hadrons})$ and $\Gamma (Z\to b\overline{b})$. We treat the dependence on the top quark mass exactly instead of using a large mass expansion. The present work completes the evaluation of the ${\alpha }_s^2$ contributions to these quantities. The calculation uses both the $\overline{\mathrm{MS}}$ and Collins-Wilczek-Zee renormalization prescriptions. The results can be applied to the hadronic decays of the $\tau$-lepton.

10 pages, REVTeX 3.0 with 4 postscript figures compressed with uufiles, University of Oregon preprint OITS 545

References in corpus (2)

• Euclidean asymptotic expansions of Green functions of quantum fields (I) Expansions of products of singular functions
• The alpha_s^3 correction to Gamma (Z^0 -> hadrons)

Cited by in corpus (9)

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• Quadratic Mass Corrections of Order ${\alpha }_s^3{m}_q^2/s$ to the Decay Rate of Z- and W- Bosons
• An Analytic Extension of the $\overline{MS}$ Renormalizaton Scheme
• On the QCD perturbative expansion for e^+ e^- --> hadrons
• The Two-Loop Scale Dependence of the Static QCD Potential including Quark Masses
• Analytic Calculation of Two Loop Corrections to Heavy Quark Pair Production Vertices Induced by Light Quarks
• Light Gluino Contribution in Hadronic Decays of Z boson and tau lepton to O(alpha_s^3)
• Perturbative QCD Calculations of Total Cross Sections and Decay Widths in Hard Inclusive Processes
• Quark Mass Corrections to the Z Boson Decay Rates