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arXiv · hep-ph/0506240

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

Charles A. Nelson·Eric Gasparo Barbagiovanni·Jeffrey J. Berger·Elisa K. Pueschel·Joshua R. Wickman
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Abstract

Most of this paper consists of the derivation of general beam-referenced stage-two spin-correlation functions for the analysis of top-antitop pair-production at the Tevatron, at the Large Hadron Collider, and/or at an International Linear Collider. However, for the charged-lepton-plus-jets reaction $q \bar{q} \to t \bar{t} \to (W^+ b) (W^- \bar{b}) \to (l^{+} νb) (W^- \bar{b})$, there is a simple 3-angle spin-correlation function for determination of the relative sign of, or for measurement of a possible non-trivial phase between the two dominant $λ_b = -1/2 $ helicity amplitudes for the $t\to W^{+}b$ decay mode. For the CP-conjugate case, there is an analogous function and tests for $\bar{t} \to W^{-} \bar{b}$ decay. These results make use of W-boson longitudinal-transverse interference.

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Charles A. Nelson, Eric Gasparo Barbagiovanni, Jeffrey J. Berger, Elisa K. Pueschel, Joshua R. Wickman. 2005-09-23. Use of W-Boson Longitudinal-Transverse Interference in Top Quark Spin-Correlation Functions. https://doi.org/10.1140/epjc%2Fs2005-02409-4

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