Precise Predictions for the WBoson Mass
Abstract
Recent results for higherorder corrections to the relation between the vectorboson masses in the Standard Model and Supersymmetry are summarized. In the Standard Model, the Higgsmass dependence of the twoloop contributions to Delta r is studied. Exact results are given for the Higgsdependent twoloop corrections associated with the fermions, i.e. no expansion in the topquark and the Higgsboson mass is made. The results for the top quark are compared with results of an expansion up to nexttoleading order in the topquark mass. Agreement is found within 30 % of the twoloop result. In Supersymmetry, the twoloop QCD corrections to the stop and sbottomloop contributions to the rho parameter are presented. The twoloop corrections modify the oneloop contribution by up to 30 %; the gluino decouples for large masses. Contrary to the SM case where the QCD corrections are negative and screen the oneloop value, the corresponding corrections in the supersymmetric case are in general positive, increasing the sensitivity in the search for scalar quarks through their virtual effects in highprecision electroweak observables.
 Publication:

arXiv eprints
 Pub Date:
 August 1997
 DOI:
 10.48550/arXiv.hepph/9708321
 arXiv:
 arXiv:hepph/9708321
 Bibcode:
 1997hep.ph....8321W
 Keywords:

 High Energy Physics  Phenomenology
 EPrint:
 14 pages, LaTeX, 4 Postscript figures