A minimal U(1)′ extension of MSSM in light of the B decay anomaly

106

We present a model to explain LHCb's recent measurements of R K and R K * based on an anomaly-free, spontaneously-broken U (1) F gauge symmetry, without any fermionic fields beyond those of the Standard Model (SM). The model explains the hierarchical heaviness of the third family and the smallness of quark mixing. The U (1) F charges of the third family of SM fields and the Higgs doublet are set equal to their respective hypercharges. A heavy Z particle with flavour-dependent couplings can modify the [b L γ ρ s L ][µ L γ ρ µ L ] effective vertex in the desired way. The Z contribution to B s − B s mixing is suppressed by a small mixing angle connected to V ts , making the constraint coming from its measurement easier to satisfy. The model can explain R K and R K * whilst simultaneously passing other constraints, including measurements of the lepton flavour universality of Z couplings.

Section: Masses Of Gauge Bosons and Z − Z Mixingmentioning

confidence: 99%

Third family hypercharge model for $$ {R}_{K^{\left(\ast \right)}} $$ and aspects of the fermion mass problem

Allanach

Davighi

2018

106

“…Because of the flavoured symmetry, the proper structure of Yukawa interactions cannot be generated in the simplest setup. To generate the proper Yukawa matrices, one may introduce (I) U(1) (B−L) 3 -charged scalars in addition to U(1) (B−L) 3 -neutral vector-like fermions that mix with the SM quarks and leptons [20]; or (II) an additional Higgs doublet that is charged under U(1) (B−L) 3 [34][35][36]. The additional fields lead to additional collider constraints on the model; e.g., vector-like fermions should be heavier than TeV [20].…”

Section: Modelmentioning

confidence: 99%

Self-interacting dark matter with a vector mediator: kinetic mixing with the $$ \mathrm{U}{(1)}_{{\left(B-L\right)}_3} $$ gauge boson

Kamada

Yamada

Yanagida

2019

A spontaneously broken hidden U(1) h gauge symmetry can explain both the dark matter stability and the observed relic abundance. In this framework, the light gauge boson can mediate the strong dark matter self-interaction, which addresses astrophysical observations that are hard to explain in collisionless cold dark matter. Motivated by flavoured grand unified theories, we introduce right-handed neutrinos and a flavoured B − L gauge symmetry for the third family U(1) (B−L) 3. The unwanted relic of the U(1) h gauge boson decays into neutrinos via the kinetic mixing with the U(1) (B−L) 3 gauge boson. Indirect detection bounds on dark matter are systematically weakened, since dark matter annihilation results in neutrinos. However, the kinetic mixing between U(1) (B−L) 3 and U(1) Y gauge bosons are induced by quantum corrections and leads to an observable signal in direct and indirect detection experiments of dark matter. This model can also explain the baryon asymmetry of the Universe via the thermal leptogenesis. In addition, we discuss the possibility of explaining the lepton flavour universality violation in semi-leptonic B meson decays that is recently found in the LHCb experiment.

“…This class of models have been explored [75][76][77][78][79][80][81][82] by assuming family-universal U(1) charges for the MSSM fields inspired by the lepton universality of the SM. However, it is also possible to consider sets of U(1) charges in which different families of matter fields can have distinct charges [83]. Even though it seems a simple difference and it does not change the spectrum compared to the U(1) extended MSSM models with universal charges, the non-universal charges can change the particle interactions by forbidding some terms while allowing others which are not present in the case of universal U(1) charges.…”

Section: Jhep10(2021)063mentioning

confidence: 99%

Electron and muon magnetic moments and implications for dark matter and model characterisation in non-universal U(1)′ supersymmetric models

Frank

Hiçyılmaz

Mondal

et al. 2021

Self Cite

We attribute deviations of the muon and electron magnetic moments from the theoretical predictions to the presence of an additional U(1)′ supersymmetric model. We interpret the discrepancies between the muon and electron anomalous magnetic moments to be due to the presence of non-universal U(1)′ charges. In a minimally extended model, we show that requiring both deviations to be satisfied imposes constraints on the spectrum of the model, in particular on dark matter candidates and slepton masses and ordering. Choosing three benchmarks with distinct dark matter features, we study implications of the model at colliders, concentrating on variables that can distinguish our non-universal scenario from other U(1)′ implementations.