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Higher-order electroweak corrections to the partial widths and branching ratios of the Z boson

  • Ayres FreitasEmail author
Open Access
Article

Abstract

Recently, the calculation of fermionic electroweak two-loop corrections to the total width of the Z boson and hadronic Z-peak cross-section in the Standard Model has been presented, where “fermionic” refers to diagrams with closed fermion loops. Here, these results are complemented by presenting contributions of the same order for the Z-boson partial widths, which are the last missing pieces for a complete description of Z-pole physics at the fermionic two-loop order. The definition of the relevant observables and the calculational techniques are described in detail. Numerical results are presented conveniently in terms of simple parametrization formulae. Finally, the remaining theoretical uncertainties from missing higher-order corrections are analyzed and found to be small compared to the current experimental errors.

Keywords

LEP HERA and SLC Physics Standard Model 

Notes

Open Access

This article is distributed under the terms of the Creative Commons Attribution License (CC-BY 4.0), which permits any use, distribution and reproduction in any medium, provided the original author(s) and source are credited.

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Copyright information

© The Author(s) 2014

Authors and Affiliations

  1. 1.Pittsburgh Particle-physics Astro-physics & Cosmology Center (PITT-PACC), Department of Physics & AstronomyUniversity of PittsburghPittsburghU.S.A

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