Related papers: Lepton Universality in Kaon Decays
$SU(2)_L$-invariance links charged dilepton and dineutrino couplings. Phenomenological implications are worked out for flavor changing neutral currents involving strange, charm, beauty and top quark transitions in a model-independent way.…
A sterile neutrino at GeV mass scale is of particular interest in this work. Though not take part in neutrino oscillation, the sterile neutrino can induce flavor violating semileptonic and leptonic decay of $K, D$ and $B$ mesons. We…
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…
Deviations from unitarity in the three-neutrino mixing canonical picture are expected in many physics scenarios beyond the Standard Model. The mixing of new heavy neutral leptons with the three light neutrinos would in principle modify the…
In supersymmetric (SUSY) models the misalignment between fermion and sfermion families introduces unsuppressed flavor-changing processes. Even if the mass parameters are chosen to give no flavor violation, family dependent radiative…
Kaon physics can test new-physics effects in leptonic or semileptonic decays. A unitarity test of the first row of the CKM mixing matrix is obtained from the precision measurements of Kl3 widths for K{\pm}, KL, and (unique to KLOE) KS. The…
We discuss charged lepton flavour violating processes occurring in the presence of muonic atoms, such as muon-electron conversion in nuclei $\text{CR}(\mu -e, \text{ N})$, the (Coulomb enhanced) decay of muonic atoms into a pair of…
Kaon experiments are now focusing on searching for new physics beyond the standard model. For example, CERN NA62, J-PARC KOTO and J-PARC TREK-E36 experiments are starting up to study K->pi nu nu-bar decay modes, a lepton flavor violation,…
Partial compositeness as a theory of flavor in the lepton sector is assessed. We begin presenting the first systematic analysis of neutrino mass generation in this context, and identifying the distinctive mass textures. We then update the…
Searches for lepton flavour and lepton number violation in kaon decays by the NA48/2 and NA62 experiments at CERN are presented. A new measurement of the helicity suppressed ratio of charged kaon leptonic decay rates $RK=BR(Ke2)/BR(Kmu2) to…
Rare kaon decays provide unique opportunity to test the Standard Model and probe its possible extensions. The final result on the lepton universality test by measuring the ratio R_K = G(K+- to e+- nu)/G(K+- to mu+- nu) is presented as well…
We present our study of lepton flavour violating decays of a Higgs boson with properties compatible with those of the particle recently discovered at the LHC. We worked in the context of the inverse seesaw model, considering the most…
Minimal extensions of the Standard Model that are motivated by grand unified theories or superstring models with an E_6 symmetry can naturally predict heavy neutrinos of Dirac or Majorana nature. Such heavy neutral leptons violate the de-…
We perform a detailed study of the $\text{b} \to \text{c} \tau \nu$ and $\text{b} \to \text{s} l^+ l^-$ processes in a minimal flipped 331 model based on the $SU(3)_C\times SU(3)_L\times U(1)_N$ gauge symmetry. The non universal $SU(3)_L…
We present a simple extension of the Standard Model with three right-handed neutrinos in a SUSY framework, with an additional U(1$)_\text{F}$ abelian flavor symmetry with a non standard leptonic charge $L_e-L_\mu-L_\tau$ for lepton doublets…
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…
In the framework of the Standard Model with lepton mixing the radiative decay $\nu_i \rightarrow \nu_j \gamma$ of a neutrino of high ($E_\nu \sim 100 \, GeV$) and super-high ($E_\nu \ge 1 \, TeV$) energy is investigated in the Coulomb field…
A simple Standard Model Extension based on $T_7$ flavor symmetry which accommodates lepton mass and mixing with non-zero $\theta_{13}$ and CP violation phase is proposed. At the tree- level, the realistic lepton mass and mixing pattern is…
We propose a novel method to probe the persistent hints of Lepton Flavour Universality violation observed in semileptonic $B$ decays. Relying on the specific properties of the Belle II experiment, it consists in comparing the inclusive…
We perform a global analysis of a vector-like extension of the Standard Model, which also features additional doublet and singlet scalars. The usual Yukawa interactions are forbidden in this setup by an extra U(1) global symmetry and the…