Journal of High Energy Physics

, 2017:44 | Cite as

B-physics anomalies: a guide to combined explanations

  • Dario ButtazzoEmail author
  • Admir Greljo
  • Gino Isidori
  • David Marzocca
Open Access
Regular Article - Theoretical Physics


Motivated by additional experimental hints of Lepton Flavour Universality violation in B decays, both in charged- and in neutral-current processes, we analyse the ingredients necessary to provide a combined description of these phenomena. By means of an Effective Field Theory (EFT) approach, based on the hypothesis of New Physics coupled predominantly to the third generation of left-handed quarks and leptons, we show how this is possible. We demonstrate, in particular, how to solve the problems posed by electroweak precision tests and direct searches with a rather natural choice of model parameters, within the context of a U(2)q ×U(2) flavour symmetry. We further exemplify the general EFT findings by means of simplified models with explicit mediators in the TeV range: coloured scalar or vector leptoquarks and colour-less vectors. Among these, the case of an SU(2)L-singlet vector leptoquark emerges as a particularly simple and successful framework.


Beyond Standard Model Heavy Quark Physics 


Open Access

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Copyright information

© The Author(s) 2017

Authors and Affiliations

  • Dario Buttazzo
    • 1
    Email author
  • Admir Greljo
    • 1
    • 2
  • Gino Isidori
    • 1
  • David Marzocca
    • 1
  1. 1.Physik-InstitutUniversität ZürichZürichSwitzerland
  2. 2.Faculty of ScienceUniversity of SarajevoSarajevoBosnia and Herzegovina

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