Abstract
The measured B-meson semi-leptonic branching ratios RD and \( {R}_{D^{*}} \) have long-standing deviations between theory and experiment. We introduce a model which explains both anomalies through a single interaction by introducing a right-handed neutrino as the missing energy particle. This interaction is mediated by a heavy charged vector boson (W ′) which couples only to right-handed quarks and leptons of the Standard Model through the mixing of these particles with new vector-like fermions. Previous W ′ models for the \( {R}_{D^{\left(*\right)}} \) anomaly were strongly constrained from flavor changing neutral currents and direct collider searches for Z′ → τ τ resonances. We show that relying on right-handed fermion mixing enables us to avoid these constraints, as well as other severe bounds from electroweak precision tests and neutrino mixing.
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Asadi, P., Buckley, M.R. & Shih, D. It’s all right(-handed neutrinos): a new W ′ model for the \( {R}_{D^{{}_{\left(\ast \right)}}} \) anomaly. J. High Energ. Phys. 2018, 10 (2018). https://doi.org/10.1007/JHEP09(2018)010
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DOI: https://doi.org/10.1007/JHEP09(2018)010