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arXiv · hep-ph/0305036

Consequences of a Large Top-Quark Chiral Weak-Moment

Abstract

This talk concerns some theoretical patterns of the helicity amplitudes for t --> W b decay. The patterns involve both the standard model's four decay helicity amplitudes, A_{SM}, and also the amplitudes A_{+} in the case of an additional t_R --> b_L tensorial coupling of relative strength Λ_{+} =E_W /2 = 53 GeV. Such an additional electroweak coupling would arise if the observed top-quark has a large chiral weak-transition-moment. The A_{+} amplitudes are interpreted as corresponding to the observed top-quark decays. Three tWb-transformations A_{+}=M A_{SM}, ..., are used in simple characterization of the values of Λ_{+}, and of the mass ratios m_W/m_t, and m_b/m_t. Measurement of the sign of the η_L = +/- 0.46 helicity parameter, respectively for SM/+, due to the large interference between the W-longitudinal and W-transverse amplitudes, could exclude such a chiral weak-transition-moment in favor of the SM prediction.

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Charles A. Nelson. 2003-05-19. Consequences of a Large Top-Quark Chiral Weak-Moment. https://arxiv.org/abs/hep-ph/0305036

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