Constraints on flavor-changing Z' models by B_s mixing, Z' production, and B_s -> μ^+ μ^-

Kingman Cheung; Cheng-Wei Chiang; N. G. Deshpande; J. Jiang

doi:10.1016/j.physletb.2007.07.032

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Constraints on flavor-changing Z' models by B_s mixing, Z' production, and B_s -> μ^+ μ^-

Kingman Cheung·Cheng-Wei Chiang·N. G. Deshpande·J. Jiang

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Abstract

Certain string-inspired Z' models have non-universal interactions to three families of fermions and induced tree-level flavor-changing couplings. We use recent results on B_s-anti-B_s mixing to constrain the size of the flavor-changing couplings in the b-s sector. In some highly predictive Z' models, such a constraint on b-s coupling can be translated into the flavor-diagonal couplings. Based on the Z' production limits at the Tevatron, we obtain the limit on the leptonic couplings of Z' and then make predictions for B_s -> μ^+ μ^- branching ratios. We conclude that with the present constraints from B_s mixing and Z' production, the muonic decay of $B_s$ may not be observed at the Tevatron if the projected integrated luminosity is less than O(5-10) fb.

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Kingman Cheung, Cheng-Wei Chiang, N. G. Deshpande, J. Jiang. 2006-04-26. Constraints on flavor-changing Z' models by B_s mixing, Z' production, and B_s -> μ^+ μ^-. https://doi.org/10.1016/j.physletb.2007.07.032

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