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Related papers: Minimal $Z'$ models for flavor anomalies

200 papers

We present a new mechanism, which does not require any flavor symmetry, to explain the small Yukawa couplings and CKM mixing angles. The Yukawa matrices are assumed to be random at short distances and the hierarchical structure is generated…

High Energy Physics - Phenomenology · Physics 2009-10-31 Ann E. Nelson , Matthew J. Strassler

The flavor problem, neutrino physics and the fermion mass hierarchy are important motivations to extend the Standard Model into the TeV scale. A new family non-universal extension is presented with three Higgs doublets, one Higgs singlet…

High Energy Physics - Phenomenology · Physics 2018-01-08 S. F. Mantilla , R. Martinez

We consider scenarios with a heavy $Z^\prime$ gauge boson with flavour non-universal quark and lepton couplings with the goal to illustrate how the cancellation of gauge anomalies generated by the additional U(1)$^\prime$ gauge symmetry…

High Energy Physics - Phenomenology · Physics 2020-03-18 Jason Aebischer , Andrzej J. Buras , Maria Cerdà-Sevilla , Fulvia De Fazio

The minimal flavor structures for both quarks and leptons are proposed to address fermion mass hierarchy and flavor mixings by bi-unitary decomposition of the fermion mass matrix. The real matrix ${\bf M}_0^f$ is completely responsive to…

High Energy Physics - Phenomenology · Physics 2022-02-16 Ying Zhang

Motivated by the intriguing discrepancies in $b\to s \ell\ell$ transitions, the fermion mass problem, and a desire to preserve the accidental symmetries of the Standard Model (SM), we extend the SM by an anomalous $U(1)_X$ gauge symmetry…

High Energy Physics - Phenomenology · Physics 2021-09-15 Joe Davighi

From general analyticity and unitarity requirements on the UV theory, positivity bounds on the Wilson coefficients of the dimension-8 operators composed of 4 fermions and two derivatives appearing in the Standard Model Effective Field…

High Energy Physics - Phenomenology · Physics 2021-06-30 Quentin Bonnefoy , Emanuele Gendy , Christophe Grojean

We examine an effective field theory inspired by Little Flavor that demonstrates a new paradigm for generating quark and lepton masses in which the scale of new flavor physics can be at the few TeV level, and new $Z'$ and $W'$ bosons are…

High Energy Physics - Phenomenology · Physics 2015-09-29 Dorota M. Grabowska , David B. Kaplan

We study renormalizable extensions of the standard model that contain vector-like fermions in a (single) complex representation of the standard model gauge group. There are 11 models where the vector-like fermions Yukawa couple to the…

High Energy Physics - Phenomenology · Physics 2015-10-09 Koji Ishiwata , Zoltan Ligeti , Mark B. Wise

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

It is possible, and for several reasons attractive, to explain a collection of recent anomalies involving $b\rightarrow s\mu\mu$ processes with a $Z^{\prime}$ gauge boson coupled only to the third family in the weak eigenbasis. From this…

High Energy Physics - Phenomenology · Physics 2019-05-16 Joe Davighi

We study a new class of flavor changing interactions, which can arise in models based on extended gauge groups (rank $>$4) when new charged fermions are present together with a new neutral gauge boson. We discuss the cases in which the…

High Energy Physics - Phenomenology · Physics 2009-10-22 E. Nardi

A new class of flavor changing (FC) neutral interactions can arise in models based on extended gauge groups (rank $>$4) when new charged fermions are present together with new neutral gauge bosons. In some cases the FC couplings to a new…

High Energy Physics - Phenomenology · Physics 2007-05-23 Enrico Nardi

Recent anomalies in $B\to K^{(*)}\ell\ell$ meson decays are consistent with exchange of a heavy $Z'$ vector boson. Here we try to connect such new physics to understanding the origin of flavor, by gauging generation number. Phenomenological…

High Energy Physics - Phenomenology · Physics 2017-10-16 James M. Cline , Jorge Martin Camalich

We construct an anomaly-free extension of the left-right symmetric model, where the maximal flavor group is gauged and anomaly cancellation is guaranteed by adding new vectorlike fermion states. We address the question of the lowest allowed…

High Energy Physics - Phenomenology · Physics 2011-06-16 Diego Guadagnoli , Rabindra N. Mohapatra , Ilmo Sung

We study a number of models, based on a non-Abelian discrete group, that successfully reproduce the simple and predictive Yukawa textures usually associated with U(2) theories of flavor. These models allow for solutions to the solar and…

High Energy Physics - Phenomenology · Physics 2008-11-26 Alfredo Aranda , Christopher D. Carone , Richard F. Lebed

$U(1)^\prime$ extensions of the standard model with generation-dependent couplings to quarks and leptons are investigated as an explanation of anomalies in rare $B$-decays, with an emphasis on stability and predictivity up to the Planck…

High Energy Physics - Phenomenology · Physics 2022-02-02 Rigo Bause , Gudrun Hiller , Tim Höhne , Daniel F. Litim , Tom Steudtner

Recently an extension of the standard model (the Lee-Wick standard model) based on ideas of Lee and Wick (LW) was introduced. It does not contain quadratic divergences in the Higgs mass and hence solves the hierarchy puzzle. The LW-standard…

High Energy Physics - Phenomenology · Physics 2008-11-26 Timothy R. Dulaney , Mark B. Wise

We consider the possibility that the neutral-current $B$ anomalies are due to radiative corrections generated by Yukawa interactions of quarks and leptons with new vector-like quark and lepton electroweak doublets and new Standard Model…

High Energy Physics - Phenomenology · Physics 2018-12-27 B. Grinstein , S. Pokorski , G. G. Ross

The updated analysis of the LHCb Collaboration on the lepton flavor violation suggests that the new physics should couple to muons and electrons with comparable magnitudes, resulting in the anomalies in both rare decay channels, $b…

High Energy Physics - Phenomenology · Physics 2023-11-13 Sang Quang Dinh , Hieu Minh Tran

A plethora of ultraviolet completions of the Standard Model have extra U(1) gauge symmetries. In general, the associated massive $Z^\prime$ gauge boson can mediate flavor-changing neutral current processes at tree level. We consider a…

High Energy Physics - Phenomenology · Physics 2017-05-24 Patrick Foldenauer , Joerg Jaeckel