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arXiv · 1704.06188

A New Light Particle in B Decays?

Filippo Sala·David M. Straub
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Abstract

We investigate the possibility whether the tensions with SM expectations observed in several b -> sll transitions, including hints for lepton flavour non-universality, could be due to the decay of B into a new light resonance. We find that qualitative agreement with the data can be obtained with a light vector resonance dominantly decaying invisibly. This scenario predicts a shift in the muon anomalous magnetic moment that could explain the long-standing discrepancy. The most stringent constraint comes from searches for B decays with missing energy. A striking prediction is a strong q^2 dependence of the lepton flavour universality ratios R_K and R_K* that should allow to clearly confirm or rule out this possibility experimentally. We also comment on the possible connection of the invisible decay product with Dark Matter.

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Filippo Sala, David M. Straub. 2017-04-20. A New Light Particle in B Decays?. https://doi.org/10.1016/j.physletb.2017.09.072

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