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arXiv · hep-ph/0510348

Use of W-Boson Longitudinal-Transverse Interference in Top Quark Spin-Correlation Functions: II

Abstract

This continuation of the derivation of general beam-referenced stage-two spin-correlation functions is for the analysis of top-antitop pair-production at the Tevatron and at the Large Hadron Collider. Both the gluon-production and the quark-production contributions are included for the charged-lepton-plus-jets reaction p p or p bar{p} --> t bar{t} --> (W^+ b)(W^- bar{b}) --> (l^{+} nu b)(W^- bar{b}). There is a simple 4-angle beam-referenced spin-correlation function for determination of the relative sign of, or for measurement of a possible non-trivial phase between the two dominant helicity amplitudes for t --> W^{+} b decay. There is an analogous function and tests for bar{t} --> W^{-} bar{b} decay. This signature requires use of the (t bar{t}) c.m.-energy of the hadronically decaying W-boson, or the kinematically equivalent cosine of the polar-angle of W-boson emission in the anti-top (top) decay frame. Spinors and their outer-products are constructed so that the helicity-amplitude phase convention of Jacob & Wick can be used throughout for the fixing of the signs associated with this large W-boson longitudinal-transverse interference effect.

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BibTeXRIS

Charles A. Nelson, Jeffrey J. Berger, Joshua R. Wickman. 2006-03-15. Use of W-Boson Longitudinal-Transverse Interference in Top Quark Spin-Correlation Functions: II. https://doi.org/10.1140/epjc%2Fs2006-02481-2

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