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arXiv · 0912.1382

New-physics contributions to the forward-backward asymmetry in B -> K* mu+ mu-

Ashutosh Kumar Alok·Amol Dighe·Diptimoy Ghosh·David London·Joaquim Matias·Makiko Nagashima·Alejandro Szynkman
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Abstract

We study the forward-backward asymmetry (AFB) and the differential branching ratio (DBR) in B -> K* mu+ mu- in the presence of new physics (NP) with different Lorentz structures. We consider NP contributions from vector-axial vector (VA), scalar-pseudoscalar (SP), and tensor (T) operators, as well as their combinations. We calculate the effects of these new Lorentz structures in the low-q^2 and high-q^2 regions, and explain their features through analytic approximations. We find two mechanisms that can give a significant deviation from the standard-model predictions, in the direction indicated by the recent measurement of AFB by the Belle experiment. They involve the addition of the following NP operators: (i) VA, or (ii) a combination of SP and T (slightly better than T alone). These two mechanisms can be distinguished through measurements of DBR in B -> K* mu+ mu- and AFB in B -> K mu+ mu-.

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Ashutosh Kumar Alok, Amol Dighe, Diptimoy Ghosh, David London, Joaquim Matias, Makiko Nagashima, Alejandro Szynkman. 2009-12-08. New-physics contributions to the forward-backward asymmetry in B -> K* mu+ mu-. https://doi.org/10.1007/jhep02(2010)053

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