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arXiv · hep-ph/0111246

Flavour-Changing Neutral Currents and Leptophobic Z' Gauge Bosons

Karine Leroux·David London
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Abstract

Leptophobic Z' gauge bosons can appear in models with an E_6 gauge symmetry. We show that flavour-changing neutral currents can be generated in some of these models due to the mixing of the ordinary d_R, s_R and b_R quark fields with the exotic h_R. Because the Z' does not couple to charged leptons, the constraints on the flavour-changing couplings U^{Z'}_{db} and U^{Z'}_{sb} are relatively weak. Indeed, B_q--Bbar_q mixing (q=d,s) can be dominated by Z' exchange, which will affect CP-violating rate asymmetries in B decays. Rare hadronic B decays can also be affected, while decays involving charged leptons will be unchanged.

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Karine Leroux, David London. 2001-11-20. Flavour-Changing Neutral Currents and Leptophobic Z' Gauge Bosons. https://doi.org/10.1016/s0370-2693(01)01489-7

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