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Related papers: Patterns of Flavour Violation in Models with Vecto…

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We investigate the possibility of constructing models of R-violating LQD Yukawa couplings using a single U(1) flavour-symmetry group and supermultiplet charge assignments that are compatible with the known hierarchies of quark and lepton…

High Energy Physics - Phenomenology · Physics 2009-09-11 John Ellis , Smaragda Lola , Graham G. Ross

In recent years, exciting (indirect) hints for physics beyond the Standard Model (SM) have been accumulated. In particular, semi-leptonic $B$ decays show deviations from the SM predictions, which, due to the ratios $R(K^{(*)})$ and…

High Energy Physics - Phenomenology · Physics 2022-04-27 Andreas Crivellin , Joaquim Matias

Flavour Changing Neutral Current (FCNC) decays are forbidden at lowest perturbative order in the Standard Model (SM) and only allowed via quantum loops. These transitions are therefore heavily suppressed in the SM, and New Physics (NP) can…

High Energy Physics - Experiment · Physics 2026-05-19 Christoph Langenbruch

The gauge sector of the Standard Model (SM) exhibits a flavour symmetry which allows for independent unitary transformations of the fermion multiplets. In the SM the flavour symmetry is broken by the Yukawa couplings to the Higgs boson, and…

High Energy Physics - Phenomenology · Physics 2013-05-29 Th. Feldmann , M. Jung , Th. Mannel

We present an effective theory approach for a model with a left-right symmetric flavour group broken only by the Yukawa couplings. An underlying SU(2)_L x SU(2)_R x U(1)_{B-L} global symmetry is assumed without specifying the fundamental…

High Energy Physics - Phenomenology · Physics 2010-11-25 Katrin Gemmler

The extension of the standard model with pairs of the vector-like families is studied. The quark mixing matrices for the left- and right-handed charged currents, as well as those for the flavour changing neutral currents, the Z and Higgs…

High Energy Physics - Phenomenology · Physics 2007-05-23 Yu. F. Pirogov , O. V. Zenin

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

Flavour physics plays a crucial role in the search for physics beyond the Standard Model (SM). While $B$ physics offers many observables to look for deviations from the SM, the highest new physics sensitivity can be obtained in the rare…

High Energy Physics - Phenomenology · Physics 2014-12-03 Monika Blanke

We study the phenomenology of simplified $Z^\prime$ models with a global $U(2)^3$ flavour symmetry in the quark sector, broken solely by the Standard Model Yukawa couplings. This flavour symmetry, known as less-minimal flavour violation,…

High Energy Physics - Phenomenology · Physics 2020-05-13 Lorenzo Calibbi , Andreas Crivellin , Fiona Kirk , Claudio Andrea Manzari , Leonardo Vernazza

In recent years, experiments revealed intriguing hints for new physics (NP) in semi-leptonic $B$ decays. Both in charged current processes, involving $b \to c \tau \nu$ transitions, and in the neutral currents $b\to s\ell^+\ell^-$, a…

High Energy Physics - Phenomenology · Physics 2020-10-19 Andreas Crivellin , Dario Müller , Francesco Saturnino

We review the formulation of the Minimal Flavour Violation (MFV) hypothesis in the quark sector, as well as some "variations on a theme" based on smaller flavour symmetry groups and/or less minimal breaking terms. We also review how these…

High Energy Physics - Phenomenology · Physics 2015-06-04 Gino Isidori , David M. Straub

We study flavor violation in the quark sector in a purely 4D, two-site effective field theory description of the Standard Model and just their first Kaluza-Klein excitations from a warped extra dimension. The warped 5D framework can provide…

High Energy Physics - Phenomenology · Physics 2009-11-13 Kaustubh Agashe , Aleksandr Azatov , Lijun Zhu

Lepton flavour violation (LFV), and lepton flavour university violation (LFUV), are striking signatures of beyond the Standard Model (BSM) physics. Recent searches for these at the ATLAS and CMS experiments are presented, using…

High Energy Physics - Experiment · Physics 2024-05-21 Holly Pacey

Motivated by the recent experimental progress on the $R_{D^{(\ast)}}$ and $R_{K^{(\ast)}}$ anomalies in $B$-decays, we consider an extension of the Standard Model by a single vector leptoquark field. We study how one can achieve the…

High Energy Physics - Phenomenology · Physics 2020-12-14 J. Kriewald , C. Hati , J. Orloff , A. M. Teixeira

We study the implications of single leptoquark extensions of the Standard Model (SM) under the assumption that their enhanced Yukawa sectors are invariant under global Abelian flavour symmetries already present in SM mass terms. Such…

High Energy Physics - Phenomenology · Physics 2022-10-19 Ivo de Medeiros Varzielas , Jim Talbert

We analyse the possible presence of New Physics (NP) in the Flavour Sector and evaluate its potential for solving the tension between the experimental values of $\AJPKs$ and $\BTNu$ with respect to the Standard Model (SM) expectations.…

High Energy Physics - Phenomenology · Physics 2015-06-05 F. J. Botella , G. C. Branco , M. Nebot

The Kobayashi-Maskawa (KM) hypothesis about the existence of a third generation of quarks represents a cornerstone of the Standard Model (SM). Fifty years after this seminal paper, flavor physics continues to represent a privileged…

High Energy Physics - Phenomenology · Physics 2023-08-23 Gino Isidori

An overview of flavour physics and CP-violating phenomena is presented. The Standard Model quark-mixing mechanism is discussed in detail and its many successful experimental tests are summarized. Flavour-changing transitions put very…

High Energy Physics - Phenomenology · Physics 2020-04-29 Antonio Pich

Combining Pati-Salam (PS) and flavour symmetries in a renormalisable setup, we devise a scenario which produces realistic masses for the charged leptons. Flavour-symmetry breaking scalar fields in the adjoint representations of the PS gauge…

High Energy Physics - Phenomenology · Physics 2016-12-21 Thorsten Feldmann , Christoph Luhn , Paul Moch

While rare meson decays place stringent constraints on much of the flavour violating parameter space of supersymmetric models, the mixing between right-handed top and charm squarks is so far unconstrained by the available data. Such mixing…

High Energy Physics - Phenomenology · Physics 2015-06-16 Monika Blanke