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Related papers: Universal Constraints on Low-Energy Flavour Models

200 papers

The coming flavour precision era will allow to uncover various patterns of flavour violation in different New Physics scenarios. We discuss different classes of them. A simple extension of the Standard Model that generally introduces new…

High Energy Physics - Phenomenology · Physics 2013-05-22 Jennifer Girrbach

With very few exceptions, the large amount of available experimental bounds on heavy neutral leptons - HNL - have been derived relying on the assumption of the existence of a single (usually Majorana) sterile fermion state that mixes with…

High Energy Physics - Phenomenology · Physics 2022-11-24 Asmaa Abada , Pablo Escribano , Xabier Marcano , Gioacchino Piazza

Recent measurements have revealed a number of intriguing deviations from the Standard Model predictions in $B$ meson decays, in particular in observables testing lepton flavour universality. We review their experimental status and…

High Energy Physics - Phenomenology · Physics 2017-07-13 Monika Blanke

Flavor changing neutral currents coming from a new non-universal neutral Gauge-Boson and from the non-unitary quark mixing matrix for the $SU(3)_c\otimes SU(3)_L\otimes U(1)_X$ model with right handed neutrinos are studied. By imposing as…

High Energy Physics - Phenomenology · Physics 2014-11-20 Richard H. Benavides , Yithsbey Giraldo , William A. Ponce

Flavour-changing neutral currents are extremely rare processes in the standard model that can be sensitive to various new physics effects. The summary of the latest experimental results from the LHC experiments is given. Preliminary results…

High Energy Physics - Experiment · Physics 2017-11-09 Kirill Skovpen

Inspired by the recent Georgi's unparticle proposal, we study the flavor structures of the standard model (SM) particles when they couple to unparticles. At a very high energy scale, we introduce $\BZ$ charges for the SM particles, which…

High Energy Physics - Phenomenology · Physics 2008-11-26 Chuan-Hung Chen , Chao-Qiang Geng

We add an energy-independent Hamiltonian to the standard flavour oscillation one. This kind of physics might appear in theories where neutrinos couple differently to a plausible non-zero torsion of the gravitational field or more…

High Energy Physics - Phenomenology · Physics 2009-08-21 M. Bustamante , A. M. Gago , C. Pena-Garay

Contact interactions are the low-energy footprints of New Physics, so ideally, constraints upon them should be as generic and model independent as possible. Hadron colliders search for four-quark contact interactions with incident valence…

High Energy Physics - Phenomenology · Physics 2015-06-18 Sacha Davidson , Sébastien Descotes-Genon

In this study, we investigate anomalous flavour-changing neutral current (FCNC) interactions related to the top quark, particularly the $t\rightarrow q\gamma$ transition, within the Standard Model Effective Field Theory (SMEFT) framework.…

High Energy Physics - Phenomenology · Physics 2025-02-26 E. Alici

The flavour messenger sectors and their impact on the soft SUSY breaking terms are investigated in SUSY flavour models. In the case when the flavour scale M is below the SUSY breaking mediation scale M_S, the universality of soft terms,…

High Energy Physics - Phenomenology · Physics 2012-09-04 Lorenzo Calibbi , Zygmunt Lalak , Stefan Pokorski , Robert Ziegler

In models with abelian flavor symmetry the small mixing angles and mass ratios of quarks and leptons are typically given by powers of small parameters characterizing the spontaneous breaking of flavor symmetry by "flavon" fields. If the…

High Energy Physics - Phenomenology · Physics 2011-05-12 Ilja Dorsner , S. M. Barr

Flavor changing neutral currents (FCNC) decays t to H + c, t to Z + c, and H to t + bar{c} are discussed in the context of Alternative Left-Right symmetric Models (ALRM) with extra isosinglet heavy fermions where FCNC decays may take place…

High Energy Physics - Phenomenology · Physics 2009-11-11 R. Gaitan , O. G. Miranda , L. G. Cabral-Rosetti

We propose a class of Two Higgs Doublet Models where there are Flavour Changing Neutral Currents (FCNC) at tree level, but under control due to the introduction of a discrete symmetry in the full Lagrangian. It is shown that in this class…

High Energy Physics - Phenomenology · Physics 2017-09-20 Joao M. Alves , Francisco J. Botella , Gustavo C. Branco , Fernando Cornet-Gomez , Miguel Nebot

We present an overview of the indirect constraints from flavor physics on supersymmetric models. During the past few years flavor data, and in particular b -> s gamma transitions, have been extensively used in order to constrain…

High Energy Physics - Phenomenology · Physics 2009-02-02 F. Mahmoudi

A flavor-dependent model (FDM) is proposed in this work. The model extends the Standard Model by an extra $U(1)_F$ local gauge group, two scalar doublets, one scalar singlet and two right-handed neutrinos, where the additional $U(1)_F$…

High Energy Physics - Phenomenology · Physics 2024-05-29 Jin-Lei Yang , Hai-Bin Zhang , Tai-Fu Feng

We study an effective theory of flavour in which the $SU(2)_L$ interaction is `flavour-deconstructed' near the TeV scale. This arises, for example, in UV models that unify all three generations of left-handed fermions via an $Sp(6)_L$…

High Energy Physics - Phenomenology · Physics 2024-04-12 Joe Davighi , Alastair Gosnay , David J Miller , Sophie Renner

We present a global analysis of lepton-flavor-specific operators in the Standard Model Effective Field Theory (SMEFT), combining data from collider and flavor physics experiments. We systematically explore various lepton-flavor scenarios,…

High Energy Physics - Phenomenology · Physics 2025-11-11 Cornelius Grunwald , Gudrun Hiller , Kevin Kröninger , Lara Nollen

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

Meson-antimeson mixing provides the most stringent constraints on baryon- and lepton-number conserving New Physics, probing scales higher than $10^5$ TeV. In the context of the effective theory of weak interactions, these constraints…

High Energy Physics - Phenomenology · Physics 2019-11-04 Luca Silvestrini , Mauro Valli

The origin of fermion mass hierarchies and mixings is one of the unresolved and most difficult problem in high-energy physics. One possibility to address the flavour problem is by extending the Standard Model to include a family symmetry.…

High Energy Physics - Phenomenology · Physics 2015-06-18 Stephen F. King , Alexander Merle , Stefano Morisi , Yusuke Shimizu , Morimitsu Tanimoto