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arXiv · hep-ph/0306278

Supersymmetric effects in top quark decay into polarized W-boson

Junjie Cao·Robert J. Oakes·Fei Wang·Jin Min Yang
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Abstract

We investigate the one-loop supersymmetric QCD (SUSY-QCD) and electroweak (SUSY-EW) corrections to the top quark decay into a b-quark and a longitudinal or transverse W-boson. The corrections are presented in terms of the longitudinal ratio Γ(t-->W_L b)/Γ(t--> W b) and the transverse ratio Γ(t-->W_- b)/Γ(t--> W b). In most of the parameter space, both SUSY-QCD and SUSY-EW corrections to these ratios are found to be less than 1% in magnitude and they tend to have opposite signs. The corrections to the total width Γ(t-->W b) are also presented for comparison with the existing results in the literature. We find that our SUSY-EW corrections to the total width differ significantly from previous studies: the previous studies give a large correction of more than 10% in magnitude for a large part of the parameter space while our results reach only few percent at most.

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Junjie Cao, Robert J. Oakes, Fei Wang, Jin Min Yang. 2003-07-30. Supersymmetric effects in top quark decay into polarized W-boson. https://doi.org/10.1103/physrevd.68.054019

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