Related papers: Lepton number violation in tau lepton decays
Searches for lepton-flavor-violating decay of a tau lepton to a lighter mass lepton and a photon have been performed with the entire dataset of (963 +- 7) x 10^6 tau decays collected by the BaBar detector near the Upsilon(4S), Upsilon(3S)…
Using the data sample of an integrated luminosity of 2.93 fb$^{-1}$ taken at the center-of-mass energy of 3.773 GeV, we search for the Majorana neutrino in the lepton number violating decays $D\to K \pi e^+ e^+$. No significant signal is…
We have searched for lepton flavor violating $\tau$ decays with a pseudoscalar meson ($\eta$, $\eta'$ and $\pi^0$) using a data sample of 401 fb$^{-1}$ collected with the Belle detector at the KEKB asymmetric-energy $e^+e^-$ collider. No…
We study the expected sensitivity at Belle and Belle II for four-body $\tau^\mp \to X^\pm l^\mp l^\mp \nu_{\tau}$ decays where $l=e$ or $\mu$ and $X=\pi$, $K$, $\rho$ and $K^*$ mesons. These decay processes violate the total lepton number…
The $e^- e^-$ mode with lepton number $L=+2$ of the initial state is particularly suitable for studying lepton and flavor number violating reactions (LFV). In this brief report we give a summary of the study of two loop-level reactions…
We search for lepton-number- and baryon-number-violating decays $\tau^{-}\to\overline{p}e^{+}e^{-}$, $pe^{-}e^{-}$, $\overline{p}e^{+}\mu^{-}$, $\overline{p}e^{-}\mu^{+}$, $\overline{p}\mu^{+}\mu^{-}$, and $p\mu^{-}\mu^{-}$ using 921…
Recently, the LHCb collaboration reported the observation of the decay mode $B_{c}^{-}\rightarrow\overline{B}_{s}^{0}\pi^{-}$ with the largest exclusive branching fraction amongst the known decay modes of all the $B$ mesons. Here we propose…
Searches for the lepton flavour violating decay $\tau^-\rightarrow \mu^-\mu^+\mu^-$ and the lepton flavour and baryon number violating decays $\tau^-\rightarrow \bar{p}\mu^+\mu^-$ and $\tau^-\rightarrow p\mu^-\mu^-$ have been carried out…
We discuss rare meson decays $K^ + \to \pi ^ - \ell ^ + \ell '^ +$ and $D^ + \to K^ - \ell ^ + \ell '^ +$ ($\ell ,\ell ' = e,\mu $) in a supersymmetric extension of the standard model with explicit breaking of R-parity by bilinear Yukawa…
We revisit the recent limits from LHCb on a Majorana neutrino N in the mass range 250 - 5000 MeV. These limits are among the best currently available, and they will be improved soon by the addition of data from Run 2 of the LHC. LHCb…
We review the recent developments in the field of nuclear double beta decay, which is presently an important topic in both nuclear and particle physics. The mechanism of lepton number violation within the neutrinoless double beta decay is…
We have searched for lepton flavor violating decays of the tau lepton with one or two KS0 mesons in the final state. The data used in the search were collected with the CLEO II and II.V detectors at the Cornell Electron Storage Ring (CESR)…
In this short review we discuss the notion of lepton numbers. The strong evidence in favor of neutrino oscillations obtained recently in the Super-Kamiokande atmospheric neutrino experiment and in solar neutrino experiments imply that the…
As is known from previous studies the lepton number violating decays $K^+\to \pi^- + l^{+}_1 + l^{+}_2$ have good prospects to probe new physics beyond the Standard Model and provide valuable information on neutrino masses and mixing. We…
We study lepton number violating and lepton number conserving semi-leptonic decays of heavy baryons $\Lambda_b^0$ to three charged leptons and a neutrino. The decays occur through two intermediate quasi-degenerate GeV-scale sterile…
We show that within the Left-Right symmetric model, lepton number violating decays of the Higgs boson can be discovered at the LHC. The process is due to the mixing of the Higgs with the triplet that breaks parity. As a result, the Higgs…
We present selected new results on leptonic B meson decays from the BaBar experiment: searches for the decays B0->l+l-, B+->l+nu and B0->l+tau-, and B->Knunubar, where l=e or mu. The decay modes imply also their charge conjugations. We…
Decays of B mesons to states involving tau leptons can be used as a tool to search for the effects of new physics, such as those involving a charged Higgs boson. The experimental status of the decays B -> tau nu and B -> D^(*) tau nu is…
We have searched for neutrinoless tau lepton decays into three charged leptons using an 87.1 fb^{-1} data sample collected with the Belle detector at the KEKB e^+e^- collider. Since the number of signal candidate events is compatible with…
Observation of lepton number ($L$) violation by two units at colliders would provide evidence for the Majorana nature of neutrinos. We study signals of $L$-violation in the context of two popular models of neutrino masses, the type-II…