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arXiv · 1505.02026

Explaining the LHC flavour anomalies

Andreas Crivellin·Giancarlo D'Ambrosio·Julian Heeck
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Abstract

The LHC observed deviations from the Standard Model (SM) in the flavour sector: LHCb found a $4.3\,σ$ discrepancy compared to the SM in $b\to sμμ$ transitions and CMS reported a non-zero measurement of $h\toμτ$ with a significance of $2.4\,σ$. Here we discuss how these deviations from the SM can be explained, focusing on two models with gauged $L_μ-L_τ$ symmetry. The first model contains two scalar doublets and vector-like quarks while the second one employs three scalar doublets but does not require vector-like fermions. In both models, interesting correlations between $b\to sμμ$ transitions, $h\toμτ$, and $τ\to3μ$ arise.

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Andreas Crivellin, Giancarlo D'Ambrosio, Julian Heeck. 2015-05-08. Explaining the LHC flavour anomalies. https://arxiv.org/abs/1505.02026

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