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arXiv · 0801.1762

Decay of Z Boson into Photon and Unparticle

Kingman Cheung·Thomas W. Kephart·Wai-Yee Keung·Tzu-Chiang Yuan
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Abstract

We study the decay of the standard model Z boson into unparticle plus a single photon through a one-loop process. As in the anomaly type decay, only the axial-vector part of the Z coupling matching with the vector unparticle and/or the vector part of the Z coupling matching with the axial-vector unparticle can give a nonzero contribution to the decay. We show that the photon spectrum terminates at the end point in accord with Yang's theorem. Existing data on single photon production at LEP I is used to constrain the unparticle sector.

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Kingman Cheung, Thomas W. Kephart, Wai-Yee Keung, Tzu-Chiang Yuan. 2008-01-11. Decay of Z Boson into Photon and Unparticle. https://doi.org/10.1016/j.physletb.2008.03.037

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