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Related papers: Flavor Hierarchy From F-theory

200 papers

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

Building an organized Yukawa structure of quarks and leptons is an essential mission to understand fermion mass hierarchy and flavor mixing in particle physics. Inspired by the similarity of CKM and PMNS mixings, a common mass pattern for…

High Energy Physics - Phenomenology · Physics 2023-11-16 Ying Zhang

In an attempt to understand the observed patterns of lepton and quark masses, models invoking a flavor symmetry $G_f$, under which the Standard Model generations are charged, have been proposed. One particularly successful symmetry, U(2),…

High Energy Physics - Phenomenology · Physics 2014-11-17 Alfredo Aranda

We consider Yukawa couplings generated by a configuration of intersecting seven-branes in F-theory. In configurations with a single interaction point and no fluxes turned on, the Yukawa matrices have rank one. This is no longer true when…

High Energy Physics - Theory · Physics 2010-07-15 Sergio Cecotti , Miranda C. N. Cheng , Jonathan J. Heckman , Cumrun Vafa

The hierarchical structure of fermion masses and mixings strongly suggests an underlying family symmetry. In supergravity any familon field spontaneously breaking this symmetry necessarily acquires an F-term which contributes to the soft…

High Energy Physics - Phenomenology · Physics 2009-11-07 G. G. Ross , O. Vives

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

In a supersymmetric model with hierarchical squark masses we analyze a pattern of flavour symmetry breaking centered on the special role of the top Yukawa coupling and, by extension, of the full Yukawa couplings for the up-type quarks. For…

High Energy Physics - Phenomenology · Physics 2011-02-15 Riccardo Barbieri , Enrico Bertuzzo , Marco Farina , Paolo Lodone , Dmitry Zhuridov

We present a new mechanism, which does not require any flavor symmetry, to explain the small Yukawa couplings and CKM mixing angles. The Yukawa matrices are assumed to be random at short distances and the hierarchical structure is generated…

High Energy Physics - Phenomenology · Physics 2009-10-31 Ann E. Nelson , Matthew J. Strassler

In multi-Higgs-doublet models, the alignment in flavour space of all Yukawa matrices coupling to a given right-handed fermion guarantees the absence of tree-level flavour-changing neutral couplings, while introducing new sources of CP…

High Energy Physics - Phenomenology · Physics 2011-04-05 Antonio Pich

The tree level potential for a scalar multiplet of `Yukawa fields' $Y$ for one type of quarks admits the promising vacuum configuration $<Y> \propto {\rm diag}(0,0,1)$ that breaks spontaneously $SU(3)_L\times SU(3)_R$ flavour symmetry. We…

High Energy Physics - Phenomenology · Physics 2015-06-12 Jose R. Espinosa , Chee Sheng Fong , Enrico Nardi

A flavor structure with minimal parameters is proposed to address the fermion mass hierarchy and flavor mixing for quarks and leptons. Yukawa interaction is reconstructed in a new basis to show a homological flat structure for up-type…

High Energy Physics - Phenomenology · Physics 2023-02-14 Ying Zhang

We analyse the structure of Yukawa couplings in local SU(5) F-theory models with $E_8$ enhancement. In this setting the $E_8$ symmetry is broken down to SU(5) by a 7-brane configuration described by T-branes, all the Yukawa couplings are…

High Energy Physics - Theory · Physics 2016-03-18 Fernando Marchesano , Diego Regalado , Gianluca Zoccarato

We study the contraints on non-flavour-blind soft supersymmetry breaking terms coming from flavour and CP violating processes in the presence of hierarchical Yukawa couplings, and quantify how much these constraints are weakened in the…

High Energy Physics - Phenomenology · Physics 2007-05-23 P. H. Chankowski , K. Kowalska , S. Lavignac , S. Pokorski

We address the flavour problem by incorporating the hypothesis of universal strength of Yukawa couplings in the framework of a 5D GUT model compactified on an $S^1/(Z_2 \times Z_2^{\prime})$ orbifold. We show that a quantitatively…

High Energy Physics - Phenomenology · Physics 2008-11-26 Gautam Bhattacharyya , Gustavo C. Branco , Joaquim I. Silva-Marcos

We show that in F-theory GUTs, a natural explanation of flavor hierarchies in the quark and lepton sector requires a single point of E_8 enhancement in the internal geometry, from which all Yukawa couplings originate. The monodromy group…

High Energy Physics - Theory · Physics 2014-11-20 Jonathan J. Heckman , Alireza Tavanfar , Cumrun Vafa

We provide a dynamical mechanism for the generation of the Cabibbo-Kobayashi-Maskawa matrix in the context of a recently proposed model of flavor. The framework, based on the paradigm that Yukawa couplings are effective low energy couplings…

High Energy Physics - Phenomenology · Physics 2020-04-15 Emidio Gabrielli , Carlo Marzo , Luca Marzola , Kristjan Müürsepp

A bottom-up approach has been adopted to identify a flavour model that agrees with present experimental measurements. The charged fermion mass hierarchies suggest that only the top Yukawa term should be present at the renormalisable level.…

High Energy Physics - Phenomenology · Physics 2020-10-28 F. Arias-Aragon , C. Bouthelier-Madre , J. M. Cano , L. Merlo

We present a new mechanism to explain naturally and through a common flavour symmetry the mildly hierarchical neutrino masses with large mixings and the hierarchical Yukawa matrices with small mixing angles. Although this mechanism is not…

High Energy Physics - Phenomenology · Physics 2007-05-23 Oscar Vives

A bottom-up approach has been adopted to identify a flavour model that agrees with present experimental measurements. The charged fermion mass hierarchies suggest that only the top Yukawa term should be present at the renormalisable level.…

High Energy Physics - Phenomenology · Physics 2020-09-22 Luca Merlo

In F-theory, U(1) gauge symmetries are encoded in rational sections, which generate the Mordell-Weil group of the elliptic fibration of the compactification space. Recently the possible U(1) charges for global SU(5) F-theory GUTs with…

High Energy Physics - Theory · Physics 2015-07-23 Sven Krippendorf , Sakura Schafer-Nameki , Jin-Mann Wong