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Related papers: Simplified Models of Flavourful Leptoquarks

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We study flavor violation in a supersymmetric SU(5) grand unification scenario in a model-independent way employing mass insertions. We examine how the quark and the lepton sector observables restrict sfermion mixings. With a low soft…

High Energy Physics - Phenomenology · Physics 2010-04-21 Pyungwon Ko , Jae-hyeon Park , Masahiro Yamaguchi

We demonstrate that in a recently proposed unified leptoquark model based on the gauge group $SU(4)_C\times SU(2)_L \times U(1)_R$ significant deviations from the Standard Model values of $R_K$ and $R_{K^*}$ can be accommodated without any…

High Energy Physics - Phenomenology · Physics 2021-01-07 Thomas Faber , Matěj Hudec , Helena Kolešová , Yang Liu , Michal Malinský , Werner Porod , Florian Staub

The concept of lepton flavour universality (LFU), according to which the three lepton families are equivalent except for their masses, is a cornerstone prediction of the Standard Model (SM). LFU can be violated in models beyond the SM by…

High Energy Physics - Experiment · Physics 2019-05-22 Elena Graverini

The long-standing anomaly in the anomalous magnetic moment of the muon indicates the presence of chirality violating new physics contributions. A possible solution involves scalar leptoquarks with left- and right-handed couplings to the top…

High Energy Physics - Phenomenology · Physics 2017-03-29 Estefania Coluccio Leskow , Andreas Crivellin , Giancarlo D'Ambrosio , Dario Müller

We study $b \to s \ell_1^+ \ell_2^-$ transitions, both for the lepton flavour conserving $\ell_1=\ell_2$ and violating case $\ell_1 \neq \ell_2$, in a minimal extension of the Standard Model proposed in [1]. In this framework, the Standard…

High Energy Physics - Phenomenology · Physics 2026-01-23 Pietro Colangelo , Fulvia De Fazio , Davide Milillo

Extensions of the Standard Model with an Abelian gauge group are constrained by gauge anomaly cancellation, so that only a limited number of possible charge assignments is allowed without the introduction of new chiral fermions. For flavour…

High Energy Physics - Phenomenology · Physics 2021-04-23 Martin Bauer , Patrick Foldenauer , Martin Mosny

We make a comprehensive study of vector-like fermionic dark matter and flavor anomalies in a simple extension of standard model. The model is added with doublet vector-like fermions of quark and lepton types, and also a…

High Energy Physics - Phenomenology · Physics 2021-12-09 Suchismita Sahoo , Shivaramakrishna Singirala , Rukmani Mohanta

Flavor physics experiments allow to probe the accuracy of the Standard Model (SM) description at low energies, and are sensitive to new heavy gauge bosons that couple to quarks and leptons in a relevant way. The apparent anomaly in the…

High Energy Physics - Phenomenology · Physics 2018-12-26 Marcela Carena , Eugenio Megias , Mariano Quiros , Carlos Wagner

Supersymmetric B-L extension of the Standard Model (SM) is one of the best candidate for physics beyond the SM that accounts for TeV scale seesaw mechanism and provides an attractive solution for the Higgs naturalness problem. We analyze…

High Energy Physics - Phenomenology · Physics 2013-05-29 Shaaban Khalil

We perform a comprehensive search for Standard Model extensions inspired by asymptotic safety. Our models feature a singlet matrix scalar field, three generations of vector-like leptons, and direct links to the Higgs and flavor sectors via…

High Energy Physics - Phenomenology · Physics 2020-12-30 Gudrun Hiller , Clara Hormigos-Feliu , Daniel F. Litim , Tom Steudtner

We propose a model in which the Yukawa couplings of Higgs doublets are related to the couplings of the chiral fermions to a scalar leptoquark triplet. This is due to their common origin via mixing with a vector-like family distinguished by…

High Energy Physics - Phenomenology · Physics 2019-05-29 Ivo de Medeiros Varzielas , Stephen F. King

We discuss flavour dependent lepton asymmetries in the Exceptional Supersymmetric Standard Model (E$_6$SSM). In the E$_6$SSM, the right-handed neutrinos do not participate in gauge interactions, and they decay into leptons and leptoquarks.…

High Energy Physics - Phenomenology · Physics 2009-11-13 S. F. King , R. Luo , D. J. Miller , R. Nevzorov

In this dissertation, the Minimal Supersymmetric Standard Model (MSSM) is studied as a low-energy theory stemming from the $SU(5)$ Grand Unified Theory (GUT). We investigate the possibility of satisfying the minimal $SU(5)$ boundary…

High Energy Physics - Phenomenology · Physics 2015-12-01 Mateusz Iskrzyński

The gauging of the lepton flavour group is considered in the Standard Model context and in its extension with three right-handed neutrinos. The anomaly cancellation conditions lead to a Seesaw mechanism as underlying dynamics for all…

High Energy Physics - Phenomenology · Physics 2017-02-15 R. Alonso , E. Fernandez Martinez , M. B. Gavela , B. Grinstein , L. Merlo , P. Quilez

Motivated by the recent hints of lepton flavor universality violation observed in semileptonic $B$ decays, we analyze how to test flavor and helicity structures of the corresponding amplitudes in view of future data. We show that the…

High Energy Physics - Phenomenology · Physics 2019-11-21 Javier Fuentes-Martín , Gino Isidori , Julie Pagès , Kei Yamamoto

We consider a class of $\text{SO}(10)$ models with flavor symmetries in the Yukawa sector and investigate their viability by performing numerical fits to the fermion masses and mixing parameters. The fitting procedure involves a top-down…

High Energy Physics - Phenomenology · Physics 2021-09-23 Tommy Ohlsson , Marcus Pernow

Motivated by the principle of natural flavour conservation, searches for signatures of a second scalar doublet at the LHC are usually limited to models with a very restricted Yukawa structure. Strong correlations between the scalar…

High Energy Physics - Phenomenology · Physics 2015-05-05 Alejandro Celis

Whenever an anomaly in the flavour sector appears, analyses are performed examining whether it can be explained by adding a small number of carefully-chosen flavour non-universal four-fermion SMEFT operators. These analyses are typically…

High Energy Physics - Phenomenology · Physics 2026-03-05 Alakabha Datta , Jean-François Fortin , Jacky Kumar , David London , Danny Marfatia , Nicolas Sanfaçon

Recent hints for lepton-flavor non-universality in $B$-meson decays can be interpreted as hints for the existence of leptoquarks. We show that scalar leptoquarks unavoidably arise in grand unified theories, using the well-known Pati-Salam…

High Energy Physics - Phenomenology · Physics 2019-05-15 Julian Heeck , Daniele Teresi

A flavor structure with minimal parameters is proposed to address the fermion mass hierarchy and flavor mixing for quarks and leptons. Yukawa interaction is reconstructed in a new basis to show a homological flat structure for up-type…

High Energy Physics - Phenomenology · Physics 2023-02-14 Ying Zhang