Related papers: Leptonic Decays of the W-Boson in a Strong Electro…
The polarization of the $W$ boson in $t \to W b$ decay is unambiguously predicted by the Standard Model of weak interactions and is a powerful test of our understanding of the $tbW$ vertex. The subsequent $W \to l \nu$ decay serves as a…
This Letter describes the search for a new heavy charged gauge boson W' decaying into an electron and a neutrino. The data were collected with the D0 detector at the Fermilab Tevatron proton-antiproton Collider at a center-of-mass energy of…
The large cross section for t-tbar production at the LHC and at any future hadron collider provides a high-statistics and relatively clean environment for a study of W boson properties: after tagging on a leptonic decay of one of the Ws and…
The leptonic decay of the charged pion in the presence of background magnetic fields is investigated using quenched Wilson fermions. It is demonstrated that the magnetic field opens up a new channel for this decay. The magnetic…
We consider the possibility that neutrinoless double beta decay may occur in models with unbroken lepton number via the emission of a massive gauge boson with electron lepton number $-2$. We determine the shape of the $\beta\,\beta$ sum…
Strong decay probabilities are calculated using the Lorentz contracted wave functions of decay products, determined in the arbitrary dynamical scheme with the instantaneous interaction. It is shown that the decay width obtains an additional…
The radiative decay of the massive neutrino $\nu_i \rightarrow \nu_j \gamma$ in a circularly polarized electromagnetic wave is investigated within the Standard theory with lepton mixing. The decay probability in the wave field does not…
In this work, we study the lepton number violating W boson and top quark decays via intermediate on-shell Majorana neutrinos Nj into three charged leptons and a light neutrino. We discuss the neutrino oscillation effects present in the…
We study possibilities to measure the triple anomalous W-boson couplings to photon in the $e\gamma\to W\nu$ process via its lepton decay channel (with the simplest signature). We found that in the study of the $W$ quadruple momentum…
We study in a model-independent way new neutral and charged vector bosons that could give observable signals with leptonic final states at the LHC. We show, in particular, that a charged vector W' decaying into lepton plus neutrino is…
A search for a heavy right-handed W boson (W$_\mathrm{R}$) decaying to a heavy right-handed neutrino and a charged lepton in events with two same-flavor leptons (e or $\mu$) and two jets, is presented. The analysis is based on proton-proton…
We study the effect of a light charged Higgs appearing in supersymmetric models containing two Higgs doublets on the measurement of leptonic branching ratios of the W boson at LEP. We show that the $2.8 \sigma$ excess of the branching ratio…
The radiative decay of the massive neutrino $\nu_i \rightarrow \nu_j \gamma ( m_i > m_j )$ in the external electromagnetic field is analyzed in detail in the framework of the standard model with lepton mixing. It is shown, that a sort of a…
A search for W' bosons decaying to a top and a bottom quark in final states including an electron or a muon is performed with the CMS detector at the LHC. The analyzed data correspond to an integrated luminosity of 138 fb$^{-1}$ of…
We present the complete electroweak one-loop corrections to the partial widths for two-body decays of a chargino (neutralino) into a W-boson and a neutralino (chargino). We perform the calculation for the minimal and the next-to-minimal…
A search for a new heavy particle decaying to a pair of vector bosons (WW or WZ) is presented using data from the CMS detector corresponding to an integrated luminosity of 35.9/fb collected in proton-proton collisions at a centre-of-mass…
We derive the leptonic neutral current in the simplest little Higgs model and compute the contribution of the model to the decay width $Z \to e^+e^-$. Using the precision electroweak data we obtain a strong lower bound $f\geq 5.6$ TeV at…
We show that the $m_W$ measurement is a direct probe of New Physics (NP) contributing to lepton and missing transverse momentum ($\ell+MET$), independently from indirect tests via the electroweak fit. Such NP modifies the kinematic…
In the presented article we consider exclusive weak decays of doubly heavy baryons with spin $J=1/2$ with production of leptonic pair or a set of light mesons. Using QCD factorization theorem and spectral functions approach we obtain…
Recent measurements of semileptonic $B$-meson decays into $\tau$-leptons are somewhat higher than expected in the standard model. Although the deviations are less than 3$\sigma$, they suggest the possibility of new physics affecting…