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Related papers: Two-Higgs-doublet models with Minimal Flavour Viol…

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It is well known that generic two-Higgs-doublet models (2HDMs) suffer from potentially large Higgs-mediated flavor-changing neutral current (FCNC) problem, unless additional symmetries are imposed on the Higgs fields thereby respecting the…

High Energy Physics - Phenomenology · Physics 2015-06-17 P. Ko , Yuji Omura , Chaehyun Yu

We investigate the phenomenology of a model based on the $SU(3)_c\times SU(3)_L\times U(1)_X$ gauge theory, the so-called 331 model. In particular, we focus on the Higgs sector of the model which is composed of three $SU(3)_L$ triplet Higgs…

High Energy Physics - Phenomenology · Physics 2016-07-13 Hiroshi Okada , Nobuchika Okada , Yuta Orikasa , Kei Yagyu

The possibility of detecting double flavor violating top quark transitions at future colliders is explored in a model-independent manner using the effective Lagrangian approach through the $t \to u_i\tau \mu$ ($u_i=u,c$) decays. A Yukawa…

High Energy Physics - Phenomenology · Physics 2014-11-20 A. Fernandez , C. Pagliarone , F. Ramirez-Zavaleta , J. J. Toscano

In many extensions of the Standard Model flavour changing neutral current processes can be mediated by tree-level heavy neutral scalars and/or pseudo-scalars H^0(A^0). This generally introduces new sources of flavour violation and CP…

High Energy Physics - Phenomenology · Physics 2013-07-09 Andrzej J. Buras , Fulvia De Fazio , Jennifer Girrbach , Robert Knegjens , Minoru Nagai

Recent improved measurements of B decays probing the b->s flavour-changing neutral current have put strong constraints on flavour violation beyond the Standard Model. This talk reviews a model-independent analysis of these decays, which…

High Energy Physics - Phenomenology · Physics 2012-05-29 David M. Straub

We present the QCD corrections to R_b and to the Delta B=1 effective Hamiltonian in models with a second Higgs field that couples to the quarks respecting the criterion of Minimal Flavor Violation, thus belonging either to the (1,2)_1/2 or…

High Energy Physics - Phenomenology · Physics 2014-11-20 G. Degrassi , P. Slavich

We discuss the testability of CP-violating phases at future lepton colliders for the scenario which satisfies electric dipole moment data by destructive interferences among several phases. We consider the general but aligned two Higgs…

High Energy Physics - Phenomenology · Physics 2021-05-05 Shinya Kanemura , Mitsunori Kubota , Kei Yagyu

We propose a Three Higgs Doublet Model (3HDM) that goes beyond natural flavor conservation and in which each of the three Higgs doublets couples mainly to a single generation of fermions via non-standard Yukawa structures. A hierarchy in…

High Energy Physics - Phenomenology · Physics 2025-03-24 Wolfgang Altmannshofer , Kevin Toner

Minimal Flavour Violation (MFV) postulates that the only source of flavour changing neutral currents and CP violation, as in the Standard Model, is the CKM matrix. However it does not address the origin of fermion masses and mixing and…

High Energy Physics - Phenomenology · Physics 2011-03-28 Zygmunt Lalak , Stefan Pokorski , Graham G Ross

In the left-right symmetric model based on $SU(2)_L\times SU(2)_R\times U(1)_{B-L}$ gauge symmetry, there appear heavy neutral scalar particles mediating quark flavor changing neutral currents (FCNCs) at tree level. We consider a situation…

High Energy Physics - Phenomenology · Physics 2018-02-14 Naoyuki Haba , Hiroyuki Umeeda , Toshifumi Yamada

Flavor changing neutral current processes are studied in the littlest Higgs model with T-parity. It is found that the logarithmic divergence reported earlier in Z boson flavor changing processes is exactly canceled by contributions from…

High Energy Physics - Phenomenology · Physics 2010-04-15 Toru Goto , Yasuhiro Okada , Yasuhiro Yamamoto

A discrete symmetry between quarks and (generalized) leptons can exist in nature, and its spontaneous symmetry breaking scale can be as low as a few TeV. Such a discrete symmetry also has interesting implications for how electroweak…

High Energy Physics - Phenomenology · Physics 2014-11-17 Y. Levin , R. R. Volkas

We propose to implement the Natural Flavor Conservation criterion in the two Higgs doublet model (2HDM) to an extra U(1)_H gauge symmetry for Higgs flavor, assuming two Higgs doublets carry different U(1)_H charges. Then one can easily…

High Energy Physics - Phenomenology · Physics 2015-06-04 P. Ko , Yuji Omura , Chaehyun Yu

To study a flavour model with a non-minimal Higgs sector one must first define the symmetries of the fields; then identify what types of vacua exist and how they may break the symmetries; and finally determine whether the remnant symmetries…

High Energy Physics - Phenomenology · Physics 2014-07-18 R. Gonzalez Felipe , I. P. Ivanov , C. C. Nishi , Hugo Serodio , Joao P. Silva

In the contest of a Two Higgs Doublet Model without flavor conservation, the presence of Flavor Changing Neutral Scalar Currents may affect in particular the couplings of the top quark. Some ideas on how to look for new signals from Flavor…

High Energy Physics - Phenomenology · Physics 2007-05-23 Laura Reina

New physics thresholds which can modify the diphoton and dilepton Higgs branching ratios significantly may also provide new sources of CP and lepton flavor violation. We find that limits on electric dipole moments impose strong constraints…

High Energy Physics - Phenomenology · Physics 2015-03-20 David McKeen , Maxim Pospelov , Adam Ritz

Some aspects are considered on the flavor-nonconservation and $ CP $-violation arising from the quark mixings with singlet quarks. In certain models incorporating the singlet quarks, the contributions of the quark couplings to the neutral…

High Energy Physics - Phenomenology · Physics 2007-05-23 Katsuji Yamamoto

The most general Two Higgs Doublet Model potential without explicit CP violation depends on 10 real independent parameters. Excluding spontaneous CP violation results in two 7 parameter models. Although both models give rise to 5 scalar…

High Energy Physics - Phenomenology · Physics 2009-01-07 L. Brücher , R. Santos

Lepton flavor violating Higgs decays can arise in flavor symmetry models where the Higgs sector is responsible for both the electroweak and the flavor symmetry breaking. Here we advocate an $S_4$ three-Higgs-doublet model where tightly…

High Energy Physics - Phenomenology · Physics 2015-07-01 Miguel D. Campos , A. E. Cárcamo Hernández , Heinrich Päs , Erik Schumacher

After a brief review of the minimal flavour violation hypothesis and its implementation in the MSSM, the most general parametrisation of the soft supersymmetry-breaking terms by means of the charged lepton and neutrino spurions is…

High Energy Physics - Phenomenology · Physics 2009-03-27 Lorenzo Mercolli