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Related papers: Flavour in supersymmetry: horizontal symmetries or…

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We propose an economical model to address the mass hierarchies of quarks and charged leptons. The light generations of the left-handed fermions form doublets under an $ \mathrm{SU}(2) $ flavor symmetry, which is gauged. The generational…

High Energy Physics - Phenomenology · Physics 2023-09-22 Admir Greljo , Anders Eller Thomsen

We study a variant of the 3HDM, referred to as the BGL-3HDM, incorporating a $U(1)_1\times U(1)_2$ symmetry, which can distinguish the primary sources of mass for different fermion generations. In the version considered here, the Yukawa…

High Energy Physics - Phenomenology · Physics 2025-02-28 Dipankar Das , Miguel Levy , Anugrah M. Prasad

We consider FCNC and CP violating processes mediated by gluino exchange in generalized supersymmetric theories. We present the constraints on flavour (F) changing squark mass terms at the electroweak energy scale, focusing our analysis on…

High Energy Physics - Phenomenology · Physics 2007-05-23 E. Gabrielli , A. Masiero , L. Silvestrini

Flavor changing neutral currents (FCNCs) in the charm system are highly suppressed in the standard model (SM). The theoretical strategies used to suppress FCNCs induced by supersymmetry in the strange and beauty systems need not apply to…

High Energy Physics - Experiment · Physics 2007-05-23 Kwong Lau

Flavor changing neutral currents coming from a new non-universal neutral Gauge-Boson and from the non-unitary quark mixing matrix for the $SU(3)_c\otimes SU(3)_L\otimes U(1)_X$ model with right handed neutrinos are studied. By imposing as…

High Energy Physics - Phenomenology · Physics 2014-11-20 Richard H. Benavides , Yithsbey Giraldo , William A. Ponce

As a minimal theory of fermion masses we extend the SM by heavy vectorlike fermions, with flavor-anarchical Yukawa couplings, that mix with chiral fermions such that small SM Yukawa couplings arise from small mixing angles. This model can…

High Energy Physics - Phenomenology · Physics 2015-05-28 Andrzej J. Buras , Christophe Grojean , Stefan Pokorski , Robert Ziegler

We show that most features of the mass and mixing pattern of the second and third SM fermion families can be accounted for without making use of flavour symmetries or other types of flavour dynamics. We discuss the implications for flavour…

High Energy Physics - Phenomenology · Physics 2010-04-30 L. Calibbi , L. Ferretti , A. Romanino , R. Ziegler

We argue that neutrino flavor parameters may exhibit features that are very different from those of quarks and charged leptons. Specifically, within the Froggatt-Nielsen (FN) framework, charged fermion parameters depend on the ratio between…

High Energy Physics - Phenomenology · Physics 2008-11-26 Yosef Nir , Yael Shadmi

In supersymmetric grand-unified models, the lepton mixing matrix can possibly affect flavor-changing transitions in the quark sector. We present a detailed analysis of a model proposed by Chang, Masiero and Murayama, in which the…

High Energy Physics - Phenomenology · Physics 2015-05-27 Jennifer Girrbach , Sebastian Jager , Markus Knopf , Waldemar Martens , Ulrich Nierste , Christian Scherrer , Soren Wiesenfeldt

We revisit a supersymmetric flavor model based on the symmetries $SU(2)_L \times A_4 \times Z_3 \times U(1)_R$, which extends the original Altarelli and Feruglio construction by introducing flavon and driving superfields responsible for the…

High Energy Physics - Phenomenology · Physics 2025-12-10 Takaaki Nomura , Yusuke Shimizu , Towa Takahashi

We investigate an extension of the Standard Model (SM) incorporating a gauge $ U(1) $ horizontal symmetry that is free of anomalies. This extension introduces four additional un-Higgsed scalar doublets that do not develop vacuum expectation…

High Energy Physics - Phenomenology · Physics 2024-08-06 We-Fu Chang

We review the status of the flavour-changing neutral-current processes (FCNC). In particular we discuss: i) Main targets of the field, ii) The theoretical framework for FCNC, iii) Standard analysis of the unitarity triangle, iv)…

High Energy Physics - Phenomenology · Physics 2007-05-23 Andrzej J. Buras

A flavour gauge theory is observable only if the symmetry is broken at relatively low energies. The intrinsic parity-violation of the fermion representations in a flavour theory describing quark, lepton and higgsino masses and mixings…

High Energy Physics - Phenomenology · Physics 2015-03-13 Carlos A. Savoy , Marc Thormeier

We present a doubly parametric extension of the standard Froggatt--Nielsen (FN) mechanism. As is well known, mass matrices of the up- and down-type quark sectors and the charged lepton sector in the standard model can be parametrized well…

High Energy Physics - Phenomenology · Physics 2016-09-06 Kenji Nishiwaki , Yusuke Shimizu , Yoshiyuki Tatsuta

A non-universal interaction associated with top quark induces flavor changing neutral currents (FCNC) among light fermions. The size of the FCNC effect depends crucially on the dynamics of the fermion mass generation. In this paper, we…

High Energy Physics - Phenomenology · Physics 2009-10-28 X. Zhang , B. -L. Young

We construct an anomaly-free extension of the left-right symmetric model, where the maximal flavor group is gauged and anomaly cancellation is guaranteed by adding new vectorlike fermion states. We address the question of the lowest allowed…

High Energy Physics - Phenomenology · Physics 2011-06-16 Diego Guadagnoli , Rabindra N. Mohapatra , Ilmo Sung

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

We investigate, in detail, a model in which the third family fermions are subjected to an SU(2) dynamics different from the first two families. Constrained by the precision Z-pole data, the heavy gauge boson mass is bounded from below to be…

High Energy Physics - Phenomenology · Physics 2016-08-25 Ehab Malkawi , C. -P. Yuan

The masses of the charged fermion and the mixing angles among quarks are observed to be strongly hierarchical, while analogous parameters in the neutrino sector appear to be structure-less or anarchical. We develop a class of unified models…

High Energy Physics - Phenomenology · Physics 2017-11-07 K. S. Babu , Alexander Khanov , Shaikh Saad

We propose a framework that links the origin of the Standard Model flavour hierarchies to the generation of asymmetric dark matter via leptogenesis. The key new ingredient is a gauged $SO(3)$ flavour symmetry acting on both the visible and…

High Energy Physics - Phenomenology · Physics 2026-05-21 Mattias Blennow , Enrique Fernandez-Martinez , David Garcia-Garcia , Javier M. Lizana