B-physics anomalies: a guide to combined explanations
Abstract
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)ℓ 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.
- Publication:
-
Journal of High Energy Physics
- Pub Date:
- November 2017
- DOI:
- 10.1007/JHEP11(2017)044
- arXiv:
- arXiv:1706.07808
- Bibcode:
- 2017JHEP...11..044B
- Keywords:
-
- Beyond Standard Model;
- Heavy Quark Physics;
- High Energy Physics - Phenomenology;
- High Energy Physics - Experiment
- E-Print:
- 33 pages, 7 figures, 2 tables. Extended discussion and one plot added on single production of leptoquarks, typos corrected, references added