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Related papers: Flavor Changing Neutral Currents in the Lee-Wick S…

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We argue that the fermion masses and mixings are organized in a specific pattern. The approximately equal hierarchies between successive generations, the sizes of the mixing angles, the heaviness of just the top quark, and the approximate…

High Energy Physics - Phenomenology · Physics 2013-05-29 Peter W. Graham , Surjeet Rajendran

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

We explore predictive flavor models based on subgroups of the standard-model $SU(3)^5$ flavor symmetry. Restricting to products of $SU(3)$, we find that a global $SU(3)^3$ flavor symmetry, broken only by two Yukawa spurions, leads to a…

High Energy Physics - Phenomenology · Physics 2015-05-27 Thomas Appelquist , Yang Bai , Maurizio Piai

We study the behaviour of the flavour changing neutral currents in the Left-Right Symmetric Model related to the presence of spontaneous CP phases. To do this, we explore four cases corresponding to combinations of maximal and no CP…

High Energy Physics - Phenomenology · Physics 2007-05-23 Yeinzon Rodriguez , Carlos Quimbay

We suggest a novel approach towards resolving the fermion mass hierarchy problem within the framework of the Standard Model. It is shown that the observed masses and mixings can be explained with order one couplings using successive higher…

High Energy Physics - Phenomenology · Physics 2008-11-26 K. S. Babu , S. Nandi

We discuss $Z$ mediated flavour changing neutral currents within a model where the hierarchical quark and lepton masses are explained via a fourth vector-like family, together with a scalar sector consisting of two Higgs doublets augmented…

High Energy Physics - Phenomenology · Physics 2022-02-08 A. E. Cárcamo Hernández , S. F. King , H. Lee

We study the flavor-changing quark-graviton vertex that is induced at the one-loop level when gravitational interactions are coupled to the standard model. Because of the conservation of the energy-momentum tensor the corresponding form…

High Energy Physics - Phenomenology · Physics 2009-03-24 G. Degrassi , E. Gabrielli , L. Trentadue

We consider the standard model with two Higgs doublets with the most general Yukawa coupling terms (``type III''). In the model, the neutral-Higgs-mediated flavor-changing neutral currents (FCNC's) are allowed, but must be reasonably…

High Energy Physics - Phenomenology · Physics 2009-10-31 G. Cvetic , C. S. Kim , S. S. Hwang

In this work, we compile the necessary and sufficient conditions a theory has to fulfill in order to ensure general lepton flavour conservation, in the spirit of the Glashow-Weinberg criteria for the absence of flavour-changing neutral…

High Energy Physics - Phenomenology · Physics 2008-11-26 Alexander Blum , Alexander Merle

The alignment in flavour space of the Yukawa matrices of a general two-Higgs-doublet model results in the absence of tree-level flavour-changing neutral currents. In addition to the usual fermion masses and mixings, the aligned Yukawa…

High Energy Physics - Phenomenology · Physics 2015-03-17 Martin Jung , Antonio Pich , Paula Tuzón

The Littlest Higgs model with T-parity (LHT) contains new sources of flavour and CP violation both in the quark and the lepton sector. They originate from the interactions of ordinary fermions with mirror fermions mediated by new gauge…

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

We consider a model where the standard model is extended by the addition of a vector-like isosinglet down-type quark b'. We perform a chi square fit to the flavor physics data and obtain the preferred central values along with errors of all…

High Energy Physics - Phenomenology · Physics 2016-03-23 Ashutosh Kumar Alok , Subhashish Banerjee , Dinesh Kumar , S. Uma Sankar

The anomalies recently found by the LHCb collaboration in $B$-meson decays seem to point towards the existence of new physics coupled non-universally to muons and electrons. We show that a beyond-the-Standard-Model dynamics with these…

High Energy Physics - Phenomenology · Physics 2017-06-22 Eugenio Megias , Giuliano Panico , Oriol Pujolas , Mariano Quiros

Flavor physics, like cosmology, is likely in need of new basic ideas; the puzzles of elementary particle mass hierarchies and in particular the e-mu-tau and neutrino ones still remain mysteries. In this paper a new idea of dynamical…

General Physics · Physics 2009-04-06 E. M. Lipmanov

A search for flavor-changing neutral currents in top-quark decays t to Zq is performed in events produced from the decay chain t t-bar to Zq + Wb, where both vector bosons decay leptonically, producing a final state with three leptons…

High Energy Physics - Experiment · Physics 2014-05-06 CMS Collaboration

We demonstrate that flavour-changing neutral currents in the top sector, mediated by leptophilic scalars at the electroweak scale, can easily arise in scenarios of new physics, and in particular in composite Higgs models. We moreover show…

High Energy Physics - Phenomenology · Physics 2020-10-14 Nuno Castro , Mikael Chala , Ana Peixoto , Maria Ramos

The fundamental constraint on two Higgs doublet models comes from the requirement of sufficiently suppressing flavor-changing neutral currents. There are various standard approaches for dealing with this problem, but they all tend to share…

High Energy Physics - Phenomenology · Physics 2011-09-13 Jason Evans , Brian Feldstein , William Klemm , Hitoshi Murayama , Tsutomu T. Yanagida

In a general two Higgs doublet model, we study flavor changing neutral Higgs (FCNH) decays into leptons at hadron colliders, $pp \to \phi^0 \to \tau^\mp\mu^\pm +X$, where $\phi^0$ could be a CP-even scalar ($h^0$, $H^0$) or a CP-odd…

High Energy Physics - Phenomenology · Physics 2019-07-24 Wei-Shu Hou , Rishabh Jain , Chung Kao , Masaya Kohda , Brent McCoy , Amarjit Soni

We examine the decays $t\rightarrow c\gamma$ and $c Z^0$ in the Standard Model with an extra scalar doublet and no discrete symmetry preventing tree-level flavour changing neutral currents. The Yukawa couplings of the new scalars are…

High Energy Physics - Phenomenology · Physics 2009-10-22 Michael Luke , Martin J. Savage

ATLAS and CMS have observed a flavor violating decay of the Higgs to muon and tau. The fact that flavour violating couplings of the Higgs boson are exactly zero in the Standard Model suggests the mixing of the Higgs with another scalar with…

High Energy Physics - Phenomenology · Physics 2017-09-13 Venus Keus