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arXiv · 0806.2864

Landau-Yang Theorem and Decays of a Z' Boson into Two Z Bosons

Wai-Yee Keung·Ian Low·Jing Shu
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Abstract

We study the decay of a Z' boson into two Z bosons by extending the Landau-Yang theorem to a parent particle decaying into two Z bosons. For a spin-1 parent the theorem predicts: 1) there are only two possible couplings and 2) the normalized differential cross-section depends on kinematics only through a phase shift in the azimuthal angle between the two decay planes of the Z boson. When the parent is a Z' the two possible couplings are anomaly-induced and CP-violating, respectively. At the Large Hadron Collider (LHC) effects of the two couplings could be disentangled when both Z bosons decay leptonically.

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Wai-Yee Keung, Ian Low, Jing Shu. 2008-10-03. Landau-Yang Theorem and Decays of a Z' Boson into Two Z Bosons. https://doi.org/10.1103/physrevlett.101.091802

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