English

Corrections to Quark Asymmetries at LEP

High Energy Physics - Phenomenology 2008-11-26 v1

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.

Keywords

Cite

@article{arxiv.hep-ph/0411304,
  title  = {Corrections to Quark Asymmetries at LEP},
  author = {A. Freitas and K. Moenig},
  journal= {arXiv preprint arXiv:hep-ph/0411304},
  year   = {2008}
}