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Related papers: Flavour alignment in multi-Higgs-doublet models

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Numerical correlations between fermion masses and mixings could indicate the presence of a flavor symmetry at high energies. In general, the search for these correlations using low-energy data requires an estimate of leading-log radiative…

High Energy Physics - Phenomenology · Physics 2009-10-28 J. A. Aguilar-Saavedra , M. Masip

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

The long-standing flavor anomalies in $b \to s \ell^+ \ell^-$ and $b \to c \ell \nu$ persist. In this work, we explore a specific flavor-gauged two-Higgs doublet model (FG2HDM) extended by a scalar singlet, with an imposed $U(1)$ flavor…

High Energy Physics - Phenomenology · Physics 2025-05-29 Qiaoyi Wen , Fanrong Xu

In models with non-minimal Higgs sectors, enforcing (near) Higgs alignment, necessary to prevent significant deviations in the Higgs boson coupling from the standard model prediction, causes a serious fine-tuning problem. We demonstrate…

High Energy Physics - Phenomenology · Physics 2024-04-11 Hikaru Kawai , Kiyoharu Kawana , Kin-ya Oda , Kei Yagyu

In the context of two Higgs doublet models, we study the conditions required in order to have stable quasi-alignment in flavour space. We show that stability under the RGE imposes strong constraints on the flavour structure of the Yukawa…

High Energy Physics - Phenomenology · Physics 2015-01-30 F. J. Botella , G. C. Branco , António M. Coutinho , M. N. Rebelo , J. I. Silva-Marcos

We consider a simple extension of the electroweak theory, incorporating one $SU(2)_L$ doublet of colour-octet scalars with Yukawa couplings satisfying the principle of minimal flavour violation. Using the HEPfit package, we perform a global…

High Energy Physics - Phenomenology · Physics 2021-10-20 Otto Eberhardt , Víctor Miralles , Antonio Pich

Experimental study at LHC of the possible Higgs boson should soon provide accurate estimates of the Yukawa couplings $Y_{H\bar{f}f}$ for $f=t,b,\tau$. In the presence of a non-abelian discrete flavor symmetry $G_F$ (e.g. T') the usual…

High Energy Physics - Phenomenology · Physics 2013-01-04 Paul H. Frampton

It is possible that the standard model (SM) is replaced around some transition energy $\E_{tr}$ by a new, possibly Higgsless, ``flavor gauge theory'' such that the Yukawa (running) parameters of SM at $E \sim \E_{tr}$ show up an…

High Energy Physics - Phenomenology · Physics 2010-11-01 G. Cvetic , C. S. Kim

A dynamical origin of the Yukawa couplings is a promising scenario to explain the flavour puzzle. The focus of this letter is set on the role of the neutrino Majorana character: when an $O(2)_{N_R}$ flavour symmetry acts on the right-handed…

High Energy Physics - Phenomenology · Physics 2015-06-16 R. Alonso , M. B. Gavela , D. Hernandez , L. Merlo , S. Rigolin

We study flavor violating processes in the production or decay of a neutral pseudoscalar meson $P^0$ in the framework of a general two Higgs Doublet Model type III (2HDM-III). We use a version of the model where Yukawa interactions of…

High Energy Physics - Phenomenology · Physics 2010-05-28 M. Gomez-Bock , G. Lopez-Castro , L. Lopez-Lozano , A. Rosado

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

Composite Higgs extensions of the Standard Model provide an explanation for the large hierarchies between the Yukawa couplings. We study their realisation in the context of fundamental partial compositeness where the Standard Model fermions…

High Energy Physics - Phenomenology · Physics 2023-07-24 Florian Goertz , Álvaro Pastor-Gutiérrez , Jan M. Pawlowski

The Aligned Two-Higgs-Doublet Model (A2HDM) describes a particular way of enlarging the scalar sector of the Standard Model, with a second Higgs doublet which is aligned to first the one in flavour space. This implies the absence of…

High Energy Physics - Phenomenology · Physics 2015-05-20 Paula Tuzón

We analise phenomenological implications of two Higgs doublet models with Higgs flavour changing neutral currents suppressed in the quark sector by small entries of the Cabibbo-Kokayashi-Maskawa matrix. This suppression occurs in a natural…

High Energy Physics - Phenomenology · Physics 2015-09-02 M. N. Rebelo

We present a new geometric approach to the flavour decomposition of an arbitrary soft supersymmetry-breaking sector in the MSSM. Our approach is based on the geometry that results from the quark and lepton Yukawa couplings, and enables us…

High Energy Physics - Phenomenology · Physics 2014-11-20 John Ellis , Robert N. Hodgkinson , Jae Sik Lee , Apostolos Pilaftsis

The gauge interactions of any supersymmetric extension of the standard model involve new flavor mixing matrices. The assumptions involved in the construction of minimal supersymmetric models, both $SU(3) \times SU(2) \times U(1)$ and grand…

High Energy Physics - Phenomenology · Physics 2009-10-28 Nima Arkani-Hamed , Hsin-Chia Cheng , L. J. Hall

We {works done in collaboration with C.S.Kim, Yonsei Univ., Seoul, Korea} present some properties of the SM with two Higgs doublets. Unlike the minimal SM, the Yukawa couplings (in the usual ``type II'' model) converge with the increasing…

High Energy Physics - Phenomenology · Physics 2009-09-25 G. Cvetic

In many extensions of the Standard Model, the alignment in flavor space of the fermion mass matrices and the Yukawa coupling matrices can be broken. The physical scalar boson $h(125)$ could then have flavor changing couplings. In this talk,…

High Energy Physics - Phenomenology · Physics 2016-05-11 Joachim Kopp

We present a class of warped extra dimensional models whose flavor violating interactions are much suppressed compared to the usual anarchic case due to flavor alignment. Such suppression can be achieved in models where part of the global…

High Energy Physics - Phenomenology · Physics 2013-05-29 Csaba Csaki , Gilad Perez , Ze'ev Surujon , Andreas Weiler

There are four types of two-Higgs doublet models under a discrete $Z_2$ symmetry imposed to avoid tree-level flavour-changing neutral current, i.e. type-I, type-II, type-X and type-Y models. We investigate the possibility to discriminate…

High Energy Physics - Phenomenology · Physics 2014-10-22 Xiao-Dong Cheng , Ya-Dong Yang , Xing-Bo Yuan