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Corrections to Quark Asymmetries at LEP

A. Freitas·K. Moenig
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Abstract

The most precise measurement of the weak mixing angle sin^2(theta) at LEP is from the forward-backward asymmetry e+e- --> bbbar 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 dAfbb=0.0019+/-0.0002 and dAfbc=0.0064+/-0.0001 has been found, where the remaining theoretical uncertainty is much too small to explain the apparent discrepancy between sin^2(theta) obtained from Afbb and from the left-right asymmetry at SLD.

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A. Freitas, K. Moenig. 2004-11-23. Corrections to Quark Asymmetries at LEP. https://doi.org/10.1140/epjc%2Fs2005-02164-6

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