相关论文: Heavy Majorana neutrinos in e^-e^- collisions
If the neutrinos are Majorana fermions, there are at least three new, potentially observable CP-odd phases that parameterize CP-invariance violating phenomena. We currently have no information regarding any of them and know that two out of…
At the high luminosity electron-positron circular colliders like FCC-ee in CERN and CEPC in China it will possible to measure very precisely $e^+e^-\to Z\gamma$ process with subsequent Z decay into particles invisible in the detector, that…
We discuss same-sign dilepton production mediated by Majorana neutrinos in high-energy proton-proton collisions $pp\ra \ell^+ \ell^{\prime +}X$ for $\ell,~ \ell^\prime = e,~ \mu,~ \tau$ at the LHC energy $\sqrt{s}=14$ TeV, and in the rare…
In this paper we show that the mixing between leptoquarks (LQ's) from different $SU(2)_l$ multiplets can generate a non-trivial Majorana mass matrix for neutrinos through one loop self energy diagrams. Such mixing can arise from gauge…
We investigate the reactions $e^-e^- \rightarrow W_i^-W_j^-$ for various gauge bosons production processes in the frame of the standard model with additional right-handed neutrinos and the Left-Right symmetric model. The present bounds on…
The $e^+e^-$ pair production in collisions of muon with atoms is considered to all orders in the parameter $Z\alpha$. We obtain energy distribution of $e^+$ and $e^-$ as well as energy loss of muon passing through matter with heavy atoms.…
We study the Lepton number violating like-sign dilepton processes $h_1 h_2 \to l^\pm l^{\prime \pm} jj X$ and $h_1 h_2 \to l^\pm l^{\prime \pm} W^\pm X$, mediated by heavy GeV scale Majorana neutrinos. We focus on the resonantly enhanced…
The process of collective de-excitation of atoms in a metastable level into emission mode of a single photon plus a neutrino pair, called radiative emission of neutrino pair (RENP), is sensitive to the absolute neutrino mass scale, to the…
The compelling experimental evidences for oscillations of solar, reactor, atmospheric and accelerator neutrinos imply the existence of 3-neutrino mixing in the weak charged lepton current. The current data on the 3-neutrino mixing…
We propose that the observed large leptonic mixing may just reflect a quasidegeneracy of three Majorana neutrinos. The limit of exact degeneracy of Majorana neutrinos is not trivial, as leptonic mixing and even CP violation may occur. We…
CP violation in the lepton sector, and other aspects of neutrino physics, are studied within a high scale supersymmetry model. In addition to the sneutrino vacuum expectation values (VEVs), the heavy vector-like triplet also contributes to…
A search for a heavy neutral lepton N of Majorana nature decaying into a W boson and a charged lepton is performed using the CMS detector at the LHC. The targeted signature consists of three prompt charged leptons in any flavor combination…
In the type-I seesaw model the size of mixing between light and heavy neutrinos, nu and N, respectively, is of order the square root of their mass ratio, (m_nu/m_N)^(1/2), with only one generation of the neutrinos. Since the light-neutrino…
Theoretical and experimental situation in physics of heavy neutrinos $(M_N>M_Z)$ is briefly presented. Various experimental bounds on heavy neutrino masses and mixings are shortly reviewed. Special attention is paid to possibility of…
Small neutrino masses can be sourced by a tiny vacuum expectation value of a leptophilic Higgs doublet, and mediated by Quasi-Dirac heavy neutrinos. In such simplest linear seesaw picture the neutrino mass mediators can be accessible to…
We propose a new strategy to probe heavy neutrinos with non-universal fermion couplings at the Large Hadron Collider (LHC) using a novel production mechanism and machine-learning algorithms. Focusing on proton--proton collisions at…
A Majorana mass term for the $\tau$ neutrino would induce neutrino - antineutrino mixing and thereby a process which violates fermion number by two units. We study the possibility of distinguishing between a massive Majorana and a Dirac…
The CMS $e^+ e^- jj$ events of invariant mass near 2 TeV are consistent with a $W'$ boson decaying into an electron and a right-handed neutrino whose TeV-scale mass is of the Dirac type. We show that the Dirac partner of the right-handed…
We investigate the sensitivity of some weak processes to the simplest extension of the Standard Model with Majorana neutrinos mixing in the leptonic sector. Values for mixing angles and masses compatible with several experimental…
The production of the three normal neutrinos via $e^-e+$ collision at $Z$-boson peak (neutrino production in a Z-factory) is investigated thoroughly. The differences of $\nu_e$-pair production from $\nu_\mu$-pair and $\nu_\tau$-pair…