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arXiv · 1302.3909

BR(Bs to mu+ mu-) as an electroweak precision test

Diego Guadagnoli·Gino Isidori
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Abstract

Using an effective-theory approach, we analyze the impact of BR(Bs to mu+ mu-) in constraining new-physics models that predict modifications of the Z-boson couplings to down-type quarks. Under motivated assumptions about the flavor structure of the effective theory, we show that the bounds presently derived from BR(Bs to mu+ mu-) on the effective Z-boson couplings are comparable (in the case of minimal flavor violation) or significantly more stringent (in the case of generic partial compositeness) with respect to those derived from observables at the Z peak.

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Diego Guadagnoli, Gino Isidori. 2013-06-11. BR(Bs to mu+ mu-) as an electroweak precision test. https://doi.org/10.1016/j.physletb.2013.05.054

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