Revisiting the vector leptoquark explanation of the B-physics anomalies

• Published in: The journal of high energy physics Vol. 2019; no. 7; pp. 1 - 36
• Main Authors: Cornella, Claudia, Fuentes-Martín, Javier, Isidori, Gino
• Format: Journal Article
• Language: English
• Published: Berlin/Heidelberg Springer Berlin Heidelberg 01-07-2019; Springer Nature B.V; SpringerOpen
• Subjects: Anomalies; Beyond Standard Model; Classical and Quantum Gravitation; Couplings; Elementary Particles; Flavor (particle physics); Heavy Quark Physics; High energy physics; Hypotheses; Leptons; Physics; Physics and Astronomy; Quantum Field Theories; Quantum Field Theory; Quantum Physics; Regular Article - Theoretical Physics; Relativity Theory; Standard model (particle physics); String Theory; Heavy Quark Physics; Beyond Standard Model
• ISSN: 1029-8479; 1029-8479
• DOI: 10.1007/JHEP07(2019)168

A
bstract
We present a thorough investigation of the vector leptoquark hypothesis for a combined explanation of the
B
-physics anomalies. We analyze this hypothesis from a twofold perspective, taking into account recent results from
B
-physics observables and high-
p
T
searches. First, using a simplified model, we determine the general conditions for a successful low-energy fit in presence of right-handed leptoquark couplings (neglected in previous analyses). Second, we show how these conditions, in particular a sizable 2-3 family mixing, can be achieved in a motivated ultraviolet completion. Our analysis reinforces the phenomenological success of the vector leptoquark hypothesis in addressing the anomalies, and its compatibility with motivated extensions of the Standard Model based on the idea of flavor non-universal gauge interactions. The implications of right-handed leptoquark couplings for a series of key low-energy observables, namely
B
s
→
ττ
and
τ
→
μ
lepton flavor violating processes, both in
τ
and in
B
decays, are discussed in detail. The role of the ultraviolet completion in precisely estimating other low-energy observables, most notably Δ
F
= 2 amplitudes, is also addressed.