English
Related papers

Related papers: Leptonic Flavor from Modular $A_4$: UV Mediators a…

200 papers

We compile information from low-energy observables sensitive to flavor-conserving 4-fermion operators with two or four leptons. Our analysis includes data from e+e- colliders, neutrino scattering on electron or nucleon targets, atomic…

High Energy Physics - Phenomenology · Physics 2017-09-13 Adam Falkowski , Martín González-Alonso , Kin Mimouni

We analyse the recent hints of Lepton Flavor Universality violations in semi-leptonic $B$ decays within a general EFT based on a $U(2)^n$ flavor symmetry acting on the light generations of SM fermions. We analyse in particular the…

High Energy Physics - Phenomenology · Physics 2017-08-02 Marzia Bordone , Gino Isidori , Sokratis Trifinopoulos

We study the lepton flavor models, whose flavor symmetries are finite subgroups of the modular group such as $S_3$ and $A_4$. In our models, couplings are also nontrivial representations of these groups and modular functions of the modulus.…

High Energy Physics - Phenomenology · Physics 2018-07-11 Tatsuo Kobayashi , Kentaro Tanaka , Takuya H. Tatsuishi

We present an updated and improved global fit analysis of current flavor and electroweak precision observables to derive bounds on unitarity deviations of the leptonic mixing matrix and on the mixing of heavy neutrinos with the active…

In recent times, SMEFT, along with a superlative repertoire of theoretical and computational tools, has emerged as an efficacious platform to test the viability of proposed BSM scenarios. With symmetry as the backbone, higher mass…

High Energy Physics - Phenomenology · Physics 2022-09-07 Wrishik Naskar , Suraj Prakash , Shakeel Ur Rahaman

We study the implications of an approximate $U(2)^5$ flavor symmetry at the TeV scale, under the assumption of new physics predominantly coupled to the third-generation fermions, focusing on the breaking of the $U(2)_\ell$ subgroup…

High Energy Physics - Phenomenology · Physics 2025-11-21 Sebastiano Covone , Pol Morell , Arianna Tinari

We present a common explanation of the fermion mass hierarchy and the large lepton mixing angles in the context of a grand unified flavor and gauge theory (GUTF). Our starting point is a SU(3)xU(1) flavor symmetry and a SO(10) GUT, a basic…

High Energy Physics - Phenomenology · Physics 2008-11-26 F. Bazzocchi , S. Morisi , M. Picariello , E. Torrente-Lujan

We investigate constraints on couplings of Standard Model effective field theory (SMEFT) operators contributing to $Wtb$ effective vertex at tree level. We study the one-loop level impact of these couplings on the low-energy flavour…

High Energy Physics - Phenomenology · Physics 2025-10-15 Subhajit Kala , Lipika Kolay , Lopamudra Mukherjee , Soumitra Nandi

We propose a E_6 inspired supersymmetric model with a non-Abelian discrete flavor symmetry (S_4 group); that is, SU(3)_c x SU(2)_W x U(1)_Y x U(1)_X x S_4 x Z_2. In our scenario, the additional abelian gauge symmetry; U(1)_X, not only…

High Energy Physics - Phenomenology · Physics 2014-11-20 Y. Daikoku , H. Okada

We propose a hidden gauged $U(1)_H$ $Z'$ model to explain deviations from the Standard Model (SM) values in lepton flavor universality known as $R_K$ and $R_D$ anomalies. The $Z'$ only interacts with the SM fermions via their mixing with…

High Energy Physics - Phenomenology · Physics 2018-06-13 Kaori Fuyuto , Hao-Lin Li , Jiang-Hao Yu

Many new physics scenarios beyond the Standard Model often necessitate the existence of a (light) neutral scalar $H$, which might couple to the charged leptons in a flavor violating way, while evading all existing constraints. We show that…

High Energy Physics - Phenomenology · Physics 2018-06-04 P. S. Bhupal Dev , Rabindra N. Mohapatra , Yongchao Zhang

As an extension of the Standard Model (SM), the 3HDM (Three-Higgs-Doublet Model) defines additional relationships among the fermions. In the visible leptonic Yukawa sector of the 3HDM, we investigate the existence of flavor symmetries under…

High Energy Physics - Phenomenology · Physics 2024-10-10 Bartosz Dziewit , Joris Vergeest , Marek Zrałek

Lepton flavor violating (LFV) interactions involving dark matter (DM) particles remain a largely unexplored area. In this study, we systematically investigate LFV DM interactions within the framework of effective field theories by analyzing…

High Energy Physics - Phenomenology · Physics 2026-01-21 Sahabub Jahedi , Jin-Han Liang , Yi Liao , Xiao-Dong Ma , Yoshiki Uchida

We study the textures of SM fermion mass matrices and their mixings in a supersymmetric adjoint SU(5) Grand Unified Theory with modular $S_4$ being the horizontal symmetry. The Yukawa entries of both quarks and leptons are expressed by…

High Energy Physics - Phenomenology · Physics 2021-03-03 Ya Zhao , Hong-Hao Zhang

We study a successful model to explain the muon anomalous magnetic moment originating from Yukawa-type interactions {in a supersymmetric theory}. Thanks to a modular $A_4$ flavor symmetry, any lepton flavor violations that spoil the model…

High Energy Physics - Phenomenology · Physics 2024-02-21 Parada T. P. Hutauruk , Dong Woo Kang , Jongkuk Kim , Hiroshi Okada

Flavor symmetries are useful to realize fermion flavor structures in the standard model. In particular, discrete $A_4$ symmetry is used to realize lepton flavor structures, and some scalars which are called flavon are introduced to break…

High Energy Physics - Phenomenology · Physics 2018-01-17 Yu Muramatsu , Takaaki Nomura , Yusuke Shimizu , Hiroshi Yokoya

We study the lepton flavor violation (LFV), the leptonic magnetic moments $(g-2)_{\mu,\,e} $ and the electric dipole moment (EDM) of the electron in the Standard-Model Effective Field Theory with the $\Gamma_N$ modular flavor symmetry. We…

High Energy Physics - Phenomenology · Physics 2022-08-24 Tatsuo Kobayashi , Hajime Otsuka , Morimitsu Tanimoto , Kei Yamamoto

Both Grand Unified symmetries and discrete flavour symmetries are appealing ways to describe apparent structures in the gauge and flavour sectors of the Standard Model. Both symmetries put constraints on the high energy behaviour of the…

High Energy Physics - Phenomenology · Physics 2014-11-20 Reinier de Adelhart Toorop , Federica Bazzocchi , Luca Merlo

We present a model of the lepton masses and flavor mixing based on the discrete group $S_4 \times Z_2$. In this model, all the charged leptons and neutrinos are assigned to the $3_\alpha$ representation of $S_4$ in the Yamanouchi bases. The…

High Energy Physics - Phenomenology · Physics 2008-11-26 He Zhang

We study a realization of neutrino masses within the linear seesaw mechanism based on non-holomorphic modular $A_4$ symmetry, extending modular-invariant flavor models beyond the conventional holomorphic framework. The model is constructed…

High Energy Physics - Phenomenology · Physics 2026-02-27 Rudra Majhi , Mitesh Kumar Behera , Rukmani Mohanta