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Corrections to quark asymmetries at LEP

  • A. FreitasEmail author
  • K. Mönig
theoretical physics

Abstract.

The most precise measurement of the weak mixing angle \(\sin^2 \theta_{\mathrm{eff}}^l\) at LEP is from the forward-backward asymmetry \(e^ + e^- \rightarrow b \overline{b}\) at the Z-pole. In this note the QED and electroweak radiative corrections to obtain the pole asymmetry from the measured asymmetry for b- and c-quarks have been calculated using ZFITTER, which has been amended to allow a consistent treatment of partial two-loop corrections for the b-quark final asymmetries. A total correction of \(\delta A_{\mathrm{FB}}^{{b}} = 0.0019 \pm 0.0002\) and \(\delta A_{\mathrm{FB}}^{{c}} = 0.0064 \pm 0.0001\) has been found, where the remaining theoretical uncertainty is much too small to explain the apparent discrepancy between \(\sin^2 \theta_{\mathrm{eff}}^l\) obtained from A FB b and from the left-right asymmetry at SLD.

Keywords

Field Theory Elementary Particle Quantum Field Theory Precise Measurement Particle Acceleration 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

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Copyright information

© Springer-Verlag Berlin/Heidelberg 2005

Authors and Affiliations

  1. 1.Fermi National Accelerator LaboratoryBataviaUSA
  2. 2.Deutsches Elektronen-Synchrotron DESYZeuthenGermany

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