Related papers: Testing $WW\gamma$ vertex in radiative muon decay
In this paper, we consider the Standard Model (SM) with one family of vector-like (VL) leptons, which couple to all three families of the SM leptons. We study the constraints on this model coming from the heavy charged lepton mass bound,…
Neutrinoless double beta decay (\( 0 \nu \beta \beta \)) is a hypothetical nuclear decay mode with important implications. In particular, observation of this decay would demonstrate that the neutrino is a Majorana particle and that lepton…
The lepton number and flavor violations are important possible ingredients of the lepton physics. The neutrinoless double beta decay and the transition of the muonium into antimuonuim are related to those violations. The former can give us…
We consider the minimal model of the seesaw mechanism by introducing two right-handed neutrinos, whose masses are comparable to the electroweak scale. This framework is attractive, since it is testable at terrestrial experiments. A critical…
The NEMO 3 experiment searches for neutrinoless double beta decay and makes precision measurements of two-neutrino double beta decay in seven isotopes. The latest two-neutrino half-life results are presented, together with the limits on…
The electroweak process $p\bar p \to \ell^\pm\nu\gamma\gamma$ is calculated at tree level, including finite W width effects. In order to obtain a gauge invariant amplitude, the imaginary parts of $WW\gamma$ triangle graphs and…
The observation of neutrinoless double-beta decay (0${\nu}{\beta}{\beta}$) would show that lepton number is violated, reveal that neutrinos are Majorana particles, and provide information on neutrino mass. A discovery-capable experiment…
To the leading order, the radiative leptonic decays $B_c \to \gamma \ell \bar \nu$ ($ \ell=e, \mu$) are studied carefully. In the study, a non-relativistic constituent quark model and the effective Lagrangian for the heavy flavour decays…
The Fermilab KTeV experiment has searched for lepton flavor violating decays of the KL meson in three decay modes. We observe no events in the signal region for any of the modes studied, and we set the following upper limits for their…
Models with explicit R-parity violation can induce new rare radiative decay modes of the $W$ boson into single supersymmetric particles which also violate lepton number. We examine the rate and signature for one such decay, $W\rightarrow…
We present a new result based on an analysis of the data collected by the MEG detector at the Paul Scherrer Institut in 2009 and 2010, in search of the lepton flavour violating decay mu->e gamma. The likelihood analysis of the combined data…
The pursuit for the genuine fundamental description, governing nature at some high-energy scale, must invariably consider the yet-unknown mechanism behind the generation of neutrino mass. Lepton-flavor violating decays $l_\alpha\to…
We propose a new channel for probing charged lepton flavor violation (CLFV): the decay of true muonium into a lepton pair of different flavor, $(\mu^+ \mu^-) \to \mu^\pm e^\mp$. This purely leptonic two-body decay provides a clean…
We investigate the muon anomalous magnetic dipole moment (MDM), the muon electric dipole moment (EDM) and the lepton-flavour-violating decays of the $\tau-$lepton, $\tau \to \mu \gamma$ and $\tau\to 3\mu$, in the CP-violating Minimal…
Viability of the \mu-\tau interchange symmetry imposed as an approximate symmetry (1) on the neutrino mass matrix {\cal M}_{\nu f} in the flavour basis (2) simultaneously on the charged lepton mass matrix M_l and the neutrino mass matrix…
Charged lepton flavor violation is forbidden in the Standard Model but possible in several new physics scenarios. In many of these models, the radiative decays $\tau^{\pm}\rightarrow\ell^{\pm}\gamma$ ($\ell=e,\mu$) are predicted to have a…
The conservation of lepton flavor is a prediction of the Standard Model and is still an excellent approximate symmetry despite our observation of neutrino oscillations. Lepton flavor violation by one or two units have been discussed for…
Experimental searches for lepton-flavor-violating coherent muon-to-electron conversion in the field of a nucleus, have been proposed to reach the unprecedented sensitivity of 10^(-16) - 10^(-18) per stopped muon. At that level, they probe…
Neutrinoless double beta decay has been the subject of intensive theoretical work as it represents the only practical approach to discovering whether neutrinos are Majorana particles or not, and whether lepton number is a conserved quantum…
We review the radiative corrections to the $\tau \to P (P) \nu_\tau [\gamma]$ decays and their implications for several SM tests: lepton universality, CKM unitarity and non-standard interactions.