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O(alpha_s) corrections to longitudinal and transverse W-bosons in top quark decays

J. G. Körner
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Abstract

In this talk we consider the O(alpha_s) radiative corrections to the decay of an unpolarized top quark into a bottom quark and a W gauge boson where the helicities of the W are specified as transverse-plus, transverse-minus and longitudinal. The O(alpha_s) radiative corrections lower the normalized longitudinal rate Gamma_L/Gamma by 0.8%. We find that the normalized transverse-plus rate Gamma_+/Gamma, which vanishes at the Born term level for m_b->0, receives radiative correction contributions at the sub-percent level. Our results are discussed in the light of recent measurements of the helicity content of the W in top quark decays by the CDF Collaboration.

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J. G. Körner. 2000-11-02. O(alpha_s) corrections to longitudinal and transverse W-bosons in top quark decays. https://arxiv.org/abs/hep-ph/0011028

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