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arXiv · hep-ph/0007086

On Measurement of Helicity Parameters in Top Quark Decay

Charles A. Nelson·L. J. Adler, Jr
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Abstract

To enable an evaluation of future measurements of the helicity parameters for " t --> W b " decay in regard to " T_FS violation", this paper considers the effects of an additional pure-imaginary coupling, (i g/2 Lambda) or (i g), associated with a specific, single additional Lorentz structure, i = S, P, S + P, ... Sizable " T_FS violation" signatures can occur for low-effective mass scales (< 320 GeV), but in most cases can be more simply excluded by 10% precision measurement of the probabilities P(W_L) and P(b_L). Signatures for excluding the presence of " T_FS violation" associated with the two dynamical phase-type ambiguities are investigated.

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Charles A. Nelson, L. J. Adler, Jr. 2000-07-11. On Measurement of Helicity Parameters in Top Quark Decay. https://doi.org/10.1007/s100520000476

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