LHCb reports the first upper limits on B0 → K+π−τ+τ− and Bs0 → K+K−τ+τ− branching fractions, with recast limits of 2.8×10−4 on B0 → K*(892)0 τ+τ− at 95% CL that improve prior bounds by an order of magnitude.
B-physics anomalies: a guide to combined explanations
10 Pith papers cite this work. Polarity classification is still indexing.
10
Pith papers citing it
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 $U(2)_q \times U(2)_\ell$ 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.
citation-role summary
background 2
citation-polarity summary
roles
background 2polarities
background 2representative citing papers
A z=6.64 Little Red Dot host shows an AGN-driven ionised outflow reaching ~5500 km/s FWHM, with low mass-loading and clear LRD spectral signatures in the compact nucleus.
The Coherence Principle supplies a falsifiable prior for Bayesian model selection by converting compatibility with a theory's validated grammar into prior weights via a maximum-entropy exponential controlled by one parameter.
Massive dark fermions modify rate distributions in B to D(*) lepton invisible decays within weak effective theory, affecting |V_cb| extraction.
Angular observables in B→D(*)ℓν decays can distinguish Lorentz structures of new physics contributions fitted to measured R(D(*)) ratios, even when those ratios agree with the Standard Model.
Perturbative symmetry-breaking corrections shift the branching ratio and normal lepton polarization asymmetry by ~3% in B → K0*(1430) μ+μ−, so larger experimental deviations would indicate new physics.
No excess above Standard Model background is observed; 95% CL limits are set on couplings of the U1 vector leptoquark model for masses 1.5-3.0 TeV.
The FCC feasibility study describes how a staged electron-positron and hadron collider could deliver precision measurements on the Higgs, electroweak bosons, and top quark while searching for physics beyond the Standard Model.
LHCb measures R(D*) and R(J/ψ); combined LHCb+Belle data yield 3.1σ tension with SM in R(D) and R(D*).
Review of the room left for B-decay anomalies inside the minimal low-energy leptoquark gauge model with SU(4)_C ⊗ SU(2)_L ⊗ U(1)_R symmetry.
citing papers explorer
-
Searches for $B^0\to K^+\pi^-\tau^+\tau^-$ and $B_s^0\to K^+K^-\tau^+\tau^-$ decays
LHCb reports the first upper limits on B0 → K+π−τ+τ− and Bs0 → K+K−τ+τ− branching fractions, with recast limits of 2.8×10−4 on B0 → K*(892)0 τ+τ− at 95% CL that improve prior bounds by an order of magnitude.
-
Probing Higgs and Top Interactions through the Muon Lens at multi-TeV Muon Colliders
A z=6.64 Little Red Dot host shows an AGN-driven ionised outflow reaching ~5500 km/s FWHM, with low mass-loading and clear LRD spectral signatures in the compact nucleus.
-
The Coherence Principle: A Falsifiable Prior for Model Selection from the Grammar of Theories
The Coherence Principle supplies a falsifiable prior for Bayesian model selection by converting compatibility with a theory's validated grammar into prior weights via a maximum-entropy exponential controlled by one parameter.
-
Probing Light Dark Fermions in $B \to D^{(*)}\ell X_{\rm inv}$ via Rate Distributions
Massive dark fermions modify rate distributions in B to D(*) lepton invisible decays within weak effective theory, affecting |V_cb| extraction.
-
Lepton Flavor Universality tests through angular observables of $\overline{B}\to D^{(\ast)}\ell\overline{\nu}$ decay modes
Angular observables in B→D(*)ℓν decays can distinguish Lorentz structures of new physics contributions fitted to measured R(D(*)) ratios, even when those ratios agree with the Standard Model.
-
Symmetry-Breaking Effects on Form Factors and Observables in $B \to K_0^*(1430)\mu^+\mu^-$ Decay
Perturbative symmetry-breaking corrections shift the branching ratio and normal lepton polarization asymmetry by ~3% in B → K0*(1430) μ+μ−, so larger experimental deviations would indicate new physics.
-
Search for a leptoquark in events with a hadronically decaying $\tau$-lepton and missing transverse momentum using $pp$ collisions at $\sqrt{s}=13$ TeV with the ATLAS detector
No excess above Standard Model background is observed; 95% CL limits are set on couplings of the U1 vector leptoquark model for masses 1.5-3.0 TeV.
-
Future Circular Collider Feasibility Study Report: Volume 1, Physics, Experiments, Detectors
The FCC feasibility study describes how a staged electron-positron and hadron collider could deliver precision measurements on the Higgs, electroweak bosons, and top quark while searching for physics beyond the Standard Model.
-
Lepton flavour universality in charged-current $B$ decays
LHCb measures R(D*) and R(J/ψ); combined LHCb+Belle data yield 3.1σ tension with SM in R(D) and R(D*).
-
Lepton non-universality in $B$-decays in the minimal leptoquark gauge model
Review of the room left for B-decay anomalies inside the minimal low-energy leptoquark gauge model with SU(4)_C ⊗ SU(2)_L ⊗ U(1)_R symmetry.