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Related papers: Quark masses, CKM angles and Lepton Flavour Univer…

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We propose a twin Pati-Salam (PS) theory of flavour broken to the $G_{4321}$ gauge group at high energies, then to the Standard Model at low energies, yielding a TeV scale vector leptoquark $U^{\mu}_1(3,1,2/3)$ which has been suggested to…

High Energy Physics - Phenomenology · Physics 2021-11-24 Stephen F. King

We give an overview of recent progress in the study of fermion mass and flavor mixing phenomena. The hints exhibited by the quark and lepton mass spectra towards possible underlying flavor symmetries, from which realistic models of mass…

High Energy Physics - Phenomenology · Physics 2014-11-17 Harald Fritzsch , Zhi-zhong Xing

The concept of lepton flavour universality (LFU), according to which the three lepton families are equivalent except for their masses, is a cornerstone prediction of the Standard Model (SM). LFU can be violated in models beyond the SM by…

High Energy Physics - Experiment · Physics 2019-05-22 Elena Graverini

We consider the possibility that the neutral-current $B$ anomalies are due to radiative corrections generated by Yukawa interactions of quarks and leptons with new vector-like quark and lepton electroweak doublets and new Standard Model…

High Energy Physics - Phenomenology · Physics 2018-12-27 B. Grinstein , S. Pokorski , G. G. Ross

We discuss $Z$ mediated flavour changing neutral currents within a model where the hierarchical quark and lepton masses are explained via a fourth vector-like family, together with a scalar sector consisting of two Higgs doublets augmented…

High Energy Physics - Phenomenology · Physics 2022-02-08 A. E. Cárcamo Hernández , S. F. King , H. Lee

We consider an universal mass matrix model which has a seesaw-invariant structure with the most general texture based on flavor 2 (\leftrightarrow) 3 symmetry common to all quarks and leptons. The CKM quark mixing matrix of the model is…

High Energy Physics - Phenomenology · Physics 2008-12-18 Hiroyuki Nishiura , Koichi Matsuda , Takeshi Fukuyama

Motivated by the measurements of $b\to s\ell^+\ell^-$ transitions, including $R(K)$ and $R(K^*)$, we examine lepton flavour (universality) violation in $B$ decays and its connections to $\mu\to e\gamma$ in generic leptoquark models.…

High Energy Physics - Phenomenology · Physics 2018-02-07 Andreas Crivellin , Dario Mueller , Adrian Signer , Yannick Ulrich

Several experiments revealed intriguing hints for lepton flavor universality (LFU) violating new physics (NP) in semi-leptonic $B$ meson decays, mainly in $b \to c \tau \nu$ and $b \to s \ell^+ \ell^-$ transitions at the $3-5\,\sigma$…

High Energy Physics - Phenomenology · Physics 2019-06-05 Andreas Crivellin , Francesco Saturnino

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

Minimal Flavour Violation in its strong or weak versions, based on $U(3)^3$ and $U(2)^3$ respectively, allows suitable extensions of the Standard Model at the TeV scale to comply with current flavour constraints in the quark sector. Here we…

High Energy Physics - Phenomenology · Physics 2016-01-27 Riccardo Barbieri , Fabrizio Senia

Anomalies in (semi)leptonic $B$-meson decays present interesting patterns that might be revealing the shape of the new physics to come. In order to understand the experimental data, we explore symmetry arguments that lead to the hypothesis…

High Energy Physics - Phenomenology · Physics 2015-05-21 Rodrigo Alonso , Benjamín Grinstein , Jorge Martin Camalich

While the LHC has not directly observed any new particle so far, experimental results from LHCb, BELLE and BABAR point towards the violation of lepton flavour universality in $b\to s\ell^{+}\ell^{-}$ and $b\to c\ell\nu$. In this context,…

High Energy Physics - Phenomenology · Physics 2018-06-13 Dario Müller

To explain quark and lepton masses and mixing angles, one has to extend the standard model, and the usual practice is to put the quarks and leptons into irreducible representations of discrete groups. We argue that discrete flavor…

High Energy Physics - Phenomenology · Physics 2016-04-27 Carl H. Albright , Robert P. Feger. , Thomas W. Kephart

We apply the discrete S_3 flavor symmetry to both lepton and quark sectors of the standard model extended by introducing one Higgs triplet and realizing the type-II seesaw mechanism for finite neutrino masses. The resultant mass matrices of…

High Energy Physics - Phenomenology · Physics 2014-11-20 Zhi-zhong Xing , Deshan Yang , Shun Zhou

We argue that flavour mixing, both in the quark and charged lepton sector, is basically determined by the lightest family mass generation mechanism. So, in the chiral symmetry limit when the up and down quark masses vanish, all the quark…

High Energy Physics - Phenomenology · Physics 2008-11-26 J. L. Chkareuli , C. D. Froggatt

Present situation in the flavour mixing of quarks and leptons is briefly reviewed and a new approach called the Minimal Flavour Mixing (MFM) is considered in detail. According to MFM the whole of the flavour mixing is basically determined…

High Energy Physics - Phenomenology · Physics 2017-08-23 J. L. Chkareuli

Rather than sticking to the full $U(3)^3$ approximate symmetry normally invoked in Minimal Flavour Violation, we analyze the consequences on the current flavour data of a suitably broken $U(2)^3$ symmetry acting on the first two generations…

High Energy Physics - Phenomenology · Physics 2011-10-26 Riccardo Barbieri , Gino Isidori , Joel Jones-Perez , Paolo Lodone , David M. Straub

Beyond Standard Model physics frequently connects flavor symmetry with a discrete group. If the discrete symmetry arises spontaneously from a gauge theory, one can maintain compatibility with quantum gravity and avoid anomalies. We provide…

High Energy Physics - Phenomenology · Physics 2018-12-18 Bradley L. Rachlin , Thomas W. Kephart

We investigate a local $SU(3)_F$ flavour symmetry for its viability in generating the masses for the quarks and charged leptons of the first two families through radiative corrections. Only the third-generation fermions get tree-level…

High Energy Physics - Phenomenology · Physics 2023-10-24 Gurucharan Mohanta , Ketan M. Patel

In view of the observed strong hierarchy of the quark and lepton masses and of the flavor mixing angles it is argued that the description of flavor mixing must take this into account. One particular interesting way to describe the flavor…

High Energy Physics - Phenomenology · Physics 2007-05-23 Harald Fritzsch