Related papers: Leptonic Flavor from Modular $A_4$: UV Mediators a…
We discuss sensitivities to lepton flavor violating (and conserving) interactions at future muon colliders, especially at $\mu^+\mu^+$ colliders. Compared with the searches for rare decays of $\mu$ and $\tau$, we find that the TeV-scale…
Motivated by the recent LHCb announcement of a $3.1\sigma$ violation of lepton-flavor universality in the ratio $R_K=\Gamma(B\to K\mu^+\mu^-)/\Gamma(B\to K e^+ e^-)$, we present an updated, comprehensive analysis of the flavor anomalies…
Seesaw models with leptonic symmetries allow right-handed (RH) neutrino masses at the electroweak scale, or even lower, at the same time having large Yukawa couplings with the Standard Model leptons, thus yielding observable effects at…
When the Higgs doublets in the 3HDM transform as a flavor triplet of the $A_4$ group, the lepton mass matrices accommodate the experimental neutrino mixing angles at arbitrary precision while maintaining the correct mass ordering of the…
We present a model for Lepton Flavor Violating (LFV) neutral current non-standard interactions of neutrinos with matter fields parameterized by $\epsilon_{\alpha \beta}^f$ with $\alpha \ne \beta$. Here, unlike the previous models, the…
The non-unitarity of the effective leptonic mixing matrix at low energies is a generic signal of extensions of the Standard Model (SM) with extra fermionic singlet particles, i.e. sterile or right-handed neutrinos, to account for the…
We study ultra-violet completions for d = 6 four-fermion operators in the standard model effective field theory (SMEFT), focusing on models that contain cold dark matter candidates. Via a diagrammatic method, we generate systematically…
In this paper, we perform a comprehensive study of Lepton Flavor Violation (LFV) in semileptonic transitions in the framework of an Effective Field Theory with general flavor structure. We account for the Renormalization Group Equations…
The Standard Model Effective Field Theory (SMEFT) offers a powerful theoretical framework for parameterizing the low-energy effects of heavy new particles with masses far above the scale of electroweak symmetry breaking. Additional light…
We define a new class of Z' models with neutral flavour-changing interactions at tree level in the down-quark sector. They are related in an exact way to elements of the quark mixing matrix due to an underlying flavoured U(1)' gauge…
SU(3) gauge theories with increasing number of light fermions are the templates of strongly interacting sectors and studying their low-energy dynamics and spectrum is important, both for understanding the strong dynamics of QCD itself, but…
We propose a minimal $A_4$ flavor symmetric model, assisted by $Z_2 \times Z_3$ symmetry, which can naturally takes care of the appropriate lepton mixing and neutrino masses via Type-I seesaw. It turns out that the framework, originated due…
In a class of neutrino mass models with modular flavor symmetries, it has been observed that CP symmetry is preserved at the fixed point (or stabilizer) of the modulus parameter $\tau = {\rm i}$, whereas significant CP violation emerges…
Discrete flavor symmetry is explored for an intrinsic property of mass matrix forms of quarks and leptons. In this paper we investigate the S3 permutation symmetry and derive the general forms of mass matrices in various types of S3…
In this paper, we present a systematic investigation on simple inverse seesaw models for neutrino masses and flavor mixing based on the modular $S^{}_4$ symmetry. Two right-handed neutrinos and three extra fermion singlets are introduced to…
In the framework of the modular symmetry approach to lepton flavour, we consider a class of theories where matter superfields transform in representations of the finite modular group $\Gamma_5 \simeq A_5$. We explicitly construct a basis…
One of the possible ways to explain the observed flavour structure of fundamental particles is to include flavor symmetries in the theories. In this work, we investigate the rare charged lepton flavour violating (cLFV) decay process ($\mu…
We explore an $A_4$-symmetric flavor based left-right symmetric model with linear seesaw mechanism and study the associated neutrino phenomenology. The framework offers the advantage of studying neutrino mass, non-unitarity effects in…
We discuss an inverse seesaw model based on right-handed fermion specific $U(1)$ gauge symmetry and $A_4$-modular symmetry. These symmetries forbid unnecessary terms and restrict structures of Yukawa interactions which are relevant to…
Lepton flavour violation has been proposed as a significant test of supersymmetric unification. Here we show that such signals are also a generic feature of supersymmetric string unified models in which there is no simple unified gauge…