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Related papers: Modified lepton couplings and the Cabibbo-angle an…

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Arguments coming from Quantum Field Theory are supplemented with a 1-loop perturbative calculation to settle the non-unitarity of mixing matrices linking renormalized mass eigenstates to bare flavor states for non-degenerate coupled…

High Energy Physics - Phenomenology · Physics 2009-07-22 Quentin Duret , Bruno Machet , M. I. Vysotsky

We construct a neutrino model of three twin neutrinos in light of the neutrino appearance excesses at LSND and MiniBooNE. The model, which includes a twin parity, naturally predicts identical lepton Yukawa structures in the Standard Model…

High Energy Physics - Phenomenology · Physics 2016-04-13 Yang Bai , Ran Lu , Sida Lu , Jordi Salvado , Ben A. Stefanek

The first row of the Cabibbo-Cobayashi-Maskawa (CKM) matrix shows a discrepancy of $\sim $$3\,\sigma$ with unitarity, known as the "Cabibbo Angle Anomaly" (CAA). This tension can be explained via modified $W$ couplings to leptons, but in…

High Energy Physics - Phenomenology · Physics 2021-05-10 Claudio Andrea Manzari

Motivated by flavor non-universality and anomalies in semi-leptonic B-meson decays, we present a general and systematic discussion about how to construct anomaly-free $U(1)'$ gauge theories based on an extended standard model with only…

High Energy Physics - Phenomenology · Physics 2018-02-01 Yong Tang , Yue-Liang Wu

Any theory that have a global spontaneously broken symmetry will imply the existence of very light neutral bosons or massless bosons (sometimes called Majorons). For most of these models we have neutrino-Majoron couplings, that appear as…

High Energy Physics - Phenomenology · Physics 2008-11-26 A. P. Lessa , O. L. G. Peres

Neutrino masses and mixings have important implications for models of fermion masses, and, most directly, for the charged lepton sector. We consider supersymmetric Abelian flavor models, where neutrino mass parameters are related to those…

High Energy Physics - Phenomenology · Physics 2009-10-31 Jonathan L. Feng , Yosef Nir , Yael Shadmi

Several experiments observed deviations from the Standard Model (SM) in the flavour sector: LHCb found a $4-5\,\sigma$ discrepancy compared to the SM in $b\to s\mu^+\mu^-$ transitions (recently supported by an Belle analysis) and CMS…

High Energy Physics - Phenomenology · Physics 2016-05-12 Andreas Crivellin

Adding right-handed neutrino singlets and/or fermion triplets to the particle content of the Standard Model allows for the implementation of the seesaw mechanism to give mass to neutrinos and, simultaneously, for the construction of…

High Energy Physics - Phenomenology · Physics 2013-12-16 Luis M. Cebola , David Emmanuel-Costa , Ricardo Gonzalez Felipe

In recent years, several observables associated to semileptonic $b \to s$ processes have been found to depart from their predicted values in the Standard Model, including a few tantalizing hints of lepton flavor universality violation. In…

High Energy Physics - Phenomenology · Physics 2019-02-20 Paulina Rocha-Moran , Avelino Vicente

We present an updated and improved global fit analysis of current flavor and electroweak precision observables to derive bounds on unitarity deviations of the leptonic mixing matrix and on the mixing of heavy neutrinos with the active…

Neutrino oscillations are well established and the relevant parameters determined with good precision, except for the CP phase, in terms of a unitary lepton mixing matrix. Seesaw extensions of the Standard Model predict unitarity deviations…

High Energy Physics - Phenomenology · Physics 2016-04-08 F. J. Escrihuela , D. V. Forero , O. G. Miranda , M. Tortola , J. W. F. Valle

We examine the charged boson and right-handed neutrino contribution to the muon g-2 anomaly in the twin Higgs models with the joint constraints of the Higgs global fit data, the precision electroweak data, the leptonic flavor changing decay…

High Energy Physics - Phenomenology · Physics 2022-12-20 Guo-Li Liu , Ping Zhou

In recent years, several deviations from the Standard Model predictions in semileptonic decays of $B$-meson might suggest the existence of new physics which would break the lepton-flavour universality. In this work, we have explored the…

High Energy Physics - Phenomenology · Physics 2020-05-20 Quan-Yi Hu , Ya-Dong Yang , Min-Di Zheng

We review the current status and implications of the anomalies (i.e. deviations from the Standard Model predictions) in semi-leptonic $B$ meson decays, both in the charged and in the neutral current. In $b\to s\ell^+\ell^-$ transitions…

High Energy Physics - Phenomenology · Physics 2023-12-25 Bernat Capdevila , Andreas Crivellin , Joaquim Matias

We perform a detailed study of the $\text{b} \to \text{c} \tau \nu$ and $\text{b} \to \text{s} l^+ l^-$ processes in a minimal flipped 331 model based on the $SU(3)_C\times SU(3)_L\times U(1)_N$ gauge symmetry. The non universal $SU(3)_L…

High Energy Physics - Phenomenology · Physics 2023-04-07 P. N. Thu , N. T. Duy , A. E. Carcamo Hernandez , D. T. Huong

Gauging a specific difference of lepton numbers such as $L_{\mu}-L_{\tau}$ is a popular model-building option, which gives rise to economical explanations for the muon anomalous magnetic moment. However, this choice of gauge group seems…

High Energy Physics - Phenomenology · Physics 2022-03-23 Gonzalo Alonso-Álvarez , James M. Cline

Charged lepton flavour violation is reappraised in the context of supersymmetric see-saw mechanism. It is pointed out that a non-trivial flavour structure of right-handed neutrinos, whose effect has been thus far less studied, can give rise…

High Energy Physics - Phenomenology · Physics 2014-05-14 Jae-hyeon Park

In previous studies we found that models with flavor-universal suppression of the neutrino-gauge couplings are compatible with NuTeV and Z-pole data. In this paper we expand our analysis to obtain constraints on flavor-dependent coupling…

High Energy Physics - Phenomenology · Physics 2007-05-23 Will Loinaz , Naotoshi Okamura , Saifuddin Rayyan , Tatsu Takeuchi , L. C. R. Wijewardhana

Assuming Majorana nature of neutrinos, a general expression for the charged lepton corrections to scaling neutrino mixing has been obtained in the context of three flavor neutrino oscillations. Non-zero value of the reactor mixing angle is…

High Energy Physics - Phenomenology · Physics 2014-01-21 S. Dev , Radha Raman Gautam , Lal Singh

We critically analyze the body of results that hints to the existence of New Physics from possible violations of lepton universality observed by the LHCb experiment in the $\mu/e$ ratios $R_{K}$ and $R_{K^*}$ to the $g-2$ lepton anomalies.…