${\cal O}(α\as \ln m_t^2)$ Non-Universal Corrections to the Decay Rate $\Gamma (Z\to b\bar{b})$

Abstract

The partial decay rate $\Gamma (Z\to b\bar{b})$ is significantly influenced by the mass of the top quark due to electroweak radiative corrections. The leading $\sim m_t^2$ and the next-to-leading contribution $\sim \ln m_t^2$ are known to be numerically of similar size. In this work we calculate the QCD corrections to the logarithmic correction using the heavy top mass expansion. The ${\cal O} (α\as \ln m_t^2)$ corrections are of the same order as the QCD corrections to the quadratic top mass term, but of different sign.

10 pages, Latex [ uses epsfig.sty, 3 figures not included ] A complete postscript file, including figures, is available via anonymous ftp at ttpux2.physik.uni-karlsruhe.de (129.13.102.139) as /ttp94-14/ttp94-14.ps, Local preprint# TTP94-14

References in corpus (3)

• Euclidean asymptotic expansions of Green functions of quantum fields (I) Expansions of products of singular functions
• Euclidean asymptotic expansions of Green functions of quantum fields (II) Combinatorics of the asymptotic operation
• Current Algebra Approach to Heavy Top Effects in $Z\to b+\bar{b}$

Cited by in corpus (10)

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• Nonfactorizable QCD and Electroweak Corrections to the Hadronic Z Boson Decay Rate
• Automatic Computation of Feynman Diagrams
• Precision Physics at LEP
• Non factorizable $O(\alpha {\alpha }_s)$ corrections to the process $Z\to b\bar{b}$
• An effective field theory approach to the QCD corrections to the large-$m_t$ $Zb\bar{b}$ vertex
• Does CPT violation affect the B_d meson life times and decay asymmetries?
• Momentum expansion of massive two-loop Feynman graphs around a finite value