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

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The introduction of a Flavour Symmetry can represent an interesting way in which one can try to find an answer to some intriguing problems in Flavour Physics, like the hierarchy between the fermion masses or the particular values of mixing…

High Energy Physics - Phenomenology · Physics 2009-05-07 Alfredo Urbano

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 2014-11-12 Luca Merlo

We construct a supersymmetric model based on $T'\otimes Z_3\otimes Z_9$ flavor symmetry. At the leading order, the charged lepton mass matrix is not diagonal, $T'$ is broken completely, and the hierarchy in the charged lepton masses is…

High Energy Physics - Phenomenology · Physics 2008-11-26 Gui-Jun Ding

If the mechanism of Supersymmetry breaking is not flavour blind, some flavour symmetry is likely to be needed to prevent excessive flavour changing neutral current effects. We discuss two flavour models (based respectively on a U(2) and on…

High Energy Physics - Phenomenology · Physics 2014-11-17 A. Masiero , M. Piai , A. Romanino , L. Silvestrini

A suitably broken U(2)^3 symmetry acting on the first two generations of quarks and squarks is studied as a natural generalization of the Minimal Flavour Violation principle to the case of a hierarchical squark spectrum. A definite…

High Energy Physics - Phenomenology · Physics 2011-10-31 David M. Straub

The smallness of fermion masses and mixing angles has recently been been attributed to approximate global $U(1)$ symmetries, one for each fermion type. The parameters associated with these symmetry breakings are estimated here directly from…

High Energy Physics - Phenomenology · Physics 2009-12-30 Lawrence Hall , Steven Weinberg

Supersymmetric theories involving a spontaneously broken flavor symmetry can solve the flavor-changing problem while having quark and lepton masses derived from both $F$ and $D$ terms. As an example, a theory of leptons is constructed in…

High Energy Physics - Phenomenology · Physics 2009-10-28 N. Arkani-Hamed , H-C Cheng , L. J Hall

Quark and lepton flavor physics presents us with a basic question: Can we understand the pattern of masses and mixings of the known quarks and leptons, and how do present and proposed measurements help to advance that goal? Topics discussed…

High Energy Physics - Phenomenology · Physics 2013-10-02 Jonathan L. Rosner

In this review article, we highlight the impact of models incorporating flavour symmetries on charged lepton flavour violating (LFV) processes. Flavour symmetries provide a natural approach to explain the peculiar mass hierarchies and…

High Energy Physics - Phenomenology · Physics 2015-06-05 Frank F. Deppisch

The confirmation of the discrepancy with the Standard Model predictions in the anomalous magnetic moment by the Muon g-2 experiment at Fermilab points to a low scale of new physics. Flavour symmetries broken at low energies can account for…

High Energy Physics - Phenomenology · Physics 2021-11-10 Lorenzo Calibbi , M. L. López-Ibáñez , Aurora Melis , Oscar Vives

We explore the possibility that lepton family numbers and baryon number are such good symmetries of Nature because they are the global remnant of a spontaneously broken gauge symmetry. An almost arbitrary linear combination of these…

High Energy Physics - Phenomenology · Physics 2020-01-15 Wolfgang Altmannshofer , Joe Davighi , Marco Nardecchia

We address the recent anomalies in semi-leptonic $B$-meson decays using a model of fermion masses based on the $U(2)$ flavor symmetry. The new contributions to $b \to s \ell \ell$ transitions arise due to a tree-level exchange of a…

High Energy Physics - Phenomenology · Physics 2016-01-20 Adam Falkowski , Marco Nardecchia , Robert Ziegler

We present a supersymmetric flavour model based on the T' discrete group, which explains fermion masses and mixings. The flavour symmetry, acting in the supersymmetric sector, provides well defined sfermion mass matrices and the resulting…

High Energy Physics - Phenomenology · Physics 2011-08-24 Luca Merlo

A grand unified $SU(5)$ theory is constructed with a hierarchical breaking of a $U(2)$ flavor symmetry. The small parameters of the squark and slepton mass matrices, necessary to solve the supersymmetric flavor-changing problem, and the…

High Energy Physics - Phenomenology · Physics 2007-05-23 Riccardo Barbieri , Lawrence Hall

Lepton flavour non-conserving processes are examined in the context of unified models with U(1)-family symmetries which reproduce successfully the low-energy hierarchy of the fermion mass spectrum and the Kobayashi - Maskawa mixing. These…

High Energy Physics - Phenomenology · Physics 2009-10-31 G. K. Leontaris , N. D. Tracas

Over the last ten years tri-bimaximal mixing has played an important role in modeling the flavour problem. We give a short review of the status of flavour symmetry models of neutrino mixing. We concentrate on non-Abelian discrete…

High Energy Physics - Phenomenology · Physics 2015-06-05 S. Morisi , J. W. F. Valle

Complex flavour couplings (off-diagonal mass terms) in the squark sector of supersymmetric theories may drastically alter both the rate and the CP-violating asymmetry of certain B-meson decays. We consider the effects of couplings that…

High Energy Physics - Phenomenology · Physics 2011-03-23 E. Lunghi , D. Wyler

U(1)-family symmetries have led to successful predictions of the fermion mass spectrum and the mixing angles of the hadronic sector. In the context of the supersymmetric unified theories, they further imply a non-trivial mass structure for…

High Energy Physics - Phenomenology · Physics 2007-05-23 Mario E. Gomez

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

Using an SU(3)-flavour symmetry breaking expansion between the strange and light quark masses, we determine how this constrains the extrapolation of baryon octet matrix elements and form factors. In particular we can construct certain…

High Energy Physics - Lattice · Physics 2021-12-09 J. M. Bickerton , A. N. Cooke , R. Horsley , Y. Nakamura , H. Perlt , D. Pleiter , P. E. L. Rakow , G. Schierholz , H. Stüben , R. D. Young , J. M. Zanotti