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Related papers: Consequences of a U(2) Flavour Symmetry

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We consider the neutrino physics of models with a sequentially broken U(2) flavor symmetry. Such theories yield the observed pattern of quark and lepton masses, while maintaining sufficient degeneracies between superparticles of the first…

High Energy Physics - Phenomenology · Physics 2014-11-17 Christopher D. Carone , Lawrence J. Hall

A properly defined and suitably broken $U(2)$ flavour symmetry leads to successful quantitative relations between quark mass ratios and CKM angles. At the same time the intrinsic distinction introduced by $U(2)$ between the third and the…

High Energy Physics - Phenomenology · Physics 2019-07-24 Riccardo Barbieri , Robert Ziegler

A general operator expansion is presented for quark and lepton mass matrices in unified theories based on a U(2) flavor symmetry, with breaking parameter of order $V_{cb} \approx m_s/m_b \approx \sqrt{m_c/m_t}$. While solving the…

High Energy Physics - Phenomenology · Physics 2009-10-30 R. Barbieri , L. J. Hall , S. Raby , A. Romanino

We show how a specific sequential breaking pattern of a U(2) flavour symmetry occurs automatically in a broad framework. The relative orientation in U(2) space of the spurion fields that breaks the U(2) symmetry is uniquely fixed, thus…

High Energy Physics - Phenomenology · Physics 2009-10-31 Riccardo Barbieri , Leonardo Giusti , Lawrence J. Hall , Andrea Romanino

We use a $U(2)\times U(1)$ horizontal symmetry in order to construct supersymmetric models where the flavor structure of both quarks and leptons is induced naturally. The supersymmetric flavor changing neutral currents problem is solved by…

High Energy Physics - Phenomenology · Physics 2009-10-31 Galit Eyal

Based on flavour symmetries only, there are two ways to give rise to an effective description of flavour physics in the quark sector close to the CKM picture: one is based on $U(3)_q\times U(3)_u\times U(3)_d$ (or equivalent) and the other…

High Energy Physics - Phenomenology · Physics 2015-06-18 Riccardo Barbieri , Dario Buttazzo , Filippo Sala , David M. Straub

It is pointed out that if a flavor symmetry (a discrete symmetry, a U(1) symmetry, and so on) exists, we cannot obtain the observed CKM quark mixing matrix V_q and MNS lepton mixing matrix U_\ell, even if we can obtain reasonable mass…

High Energy Physics - Phenomenology · Physics 2007-05-23 Yoshio Koide

We posit that the distinct patterns observed in fermion masses and mixings are due to a minimally broken $\mathrm{U}(2)_{q+e}$ flavor symmetry acting on left-handed quarks and right-handed charged leptons, giving rise to an accidental…

High Energy Physics - Phenomenology · Physics 2024-02-28 Stefan Antusch , Admir Greljo , Ben A. Stefanek , Anders Eller Thomsen

The flavour puzzle is an open problem both in the Standard Model and in its possible supersymmetric or grand unified extensions. In this thesis, we discuss possible explanations of the origin of fermion mass hierarchies and mixings by the…

High Energy Physics - Phenomenology · Physics 2010-12-16 Luca Merlo

We revisit the supersymmetric CP problem and find that it can be naturally resolved if the origin of CP violation is closely related to the origin of flavour structures. In this case, the supersymmetry breaking dynamics do not bring in any…

High Energy Physics - Phenomenology · Physics 2009-10-31 S. Abel , D. Bailin , S. Khalil , O. Lebedev

A U(2) flavor symmetry can successfully describe the charged fermion masses and mixings, and supress SUSY FCNC processes, making it a viable candidate for a theory of flavor. We show that a direct application of this U(2) flavor symmetry…

High Energy Physics - Phenomenology · Physics 2014-11-17 Lawrence J. Hall , Neal Weiner

Flavour symmetries are fundamental tools in the search for an explanation to the flavour puzzle: fermion mass hierarchies, the neutrino mass ordering, the differences between the mixing matrices in the quark and lepton sector, can all find…

High Energy Physics - Phenomenology · Physics 2015-03-12 Luca Merlo

We demonstrate the impact that present lepton flavour and CP violation data - neutrino oscillations, baryon asymmetry of the universe, flavour violations in charged lepton decays and lepton electric dipole moments - have on supersymmetric…

High Energy Physics - Phenomenology · Physics 2009-11-11 I. Masina , C. A. Savoy

The U(1) flavor symmetry explains the large mixing of neutrinos while it leads to the unique texture for the quark mass matrices. It is remarked that U(1) symmetric mass matrices have the phenomenological defects. In the quark sector, the…

High Energy Physics - Phenomenology · Physics 2008-11-26 Morimitsu Tanimoto

A U(2)^3 flavour symmetry acting on the first two generations of quarks partially explains the hierarchies of the yukawa couplings, and provides a natural embedding for Supersymmetry with heavier first two generations, where collider…

High Energy Physics - Phenomenology · Physics 2012-09-21 Filippo Sala

The so-called supersymmetric flavour and CP problems are deeply related to the origin of flavour and hence to the origin of the SM Yukawa couplings themselves. We show that realistic SU(3) flavour symmetries with spontaneous CP violation…

High Energy Physics - Phenomenology · Physics 2008-11-26 L. Calibbi , J. Jones-Perez , O. Vives

We extend a previously developed description of the flavour parameters in the charged fermion sector, based on a U(2) flavour symmetry, to include two main features of the neutrino sector seemingly implied by recent data: a large mixing…

High Energy Physics - Phenomenology · Physics 2014-11-17 Riccardo Barbieri , Paolo Creminelli , Andrea Romanino

We propose renormalizable models of new physics that can explain various anomalies observed in decays of B-mesons to electron and muon pairs. The new physics states couple to linear combinations of Standard Model fermions, yielding a…

High Energy Physics - Phenomenology · Physics 2016-07-20 Ben Gripaios , M. Nardecchia , S. A. Renner

As a consequence of the large top quark Yukawa coupling, supersymmetric unified theories with soft supersymmetry breaking terms generated at the Planck scale predict lepton flavour and CP violating processes with significant rates. The…

High Energy Physics - Phenomenology · Physics 2009-10-09 R. Barbieri , L. Hall , A. Strumia

The quark sector of the Standard Model exhibits an approximate U(2)^3 flavour symmetry. This symmetry, broken in specific directions dictated by minimality, can explain the success of the Cabibbo-Kobayashi-Maskawa picture of flavour mixing…

High Energy Physics - Phenomenology · Physics 2017-08-23 Riccardo Barbieri , Dario Buttazzo , Filippo Sala , David M. Straub
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