Related papers: Allowed slepton intergenerational mixing in light …
Evidence of a heavy neutrino, $\nu_H$, in the $K^+\to\mu^+\nu_H$ decays was sought using the E949 experimental data with an exposure of $1.70\times 10^{12}$ stopped kaons. With the major background from the radiative…
A search for long-lived heavy neutrinos (N) in the decays of B mesons produced in proton-proton collisions at $\sqrt{s}$ = 13 TeV is presented. The data sample corresponds to an integrated luminosity of 41.6 fb$^{-1}$ collected in 2018 by…
In supersymmetric scenarios where the scalar tau lepton is stable or long-lived, a search for a decay mode chi0 --> stau + mu at the LHC has a good sensitivity to the flavor mixing in the scalar lepton sector. We demonstrate that the…
Inspired by the small mass-squared difference measured in the solar neutrino oscillation experiments and by the testability, we suggest that a limit of the partial mass degeneracy, in which masses of the first two generation fermions are…
We present a phenomenological study of tau-sleptons stau_1,2 and tau-sneutrino in the Minimal Supersymmetric Standard Model with complex parameters A_tau, mu and M_1. We analyse production and decays of stau_1,2 and tau-sneutrino at a…
The cross section for the reaction $e^{-}e^{-} \to \ell^-\ell^-$ ($\ell=\mu,\tau$) is calculated in models with heavy Majorana neutrinos mediating lepton number violating amplitudes at the loop level. The contributing four-point functions…
The reported signal at the LSND experiment, when interpreted as neutrino mixing with $\delta m^2 = 6 \;\rm{eV}^2$, provides evidence for neutrinos with a cosmologically significant mass. However, attempts to reconcile this interpretation of…
The possible existence of bulk singlet neutrinos in the scenario with large compactified dimensions and low string scale $M_*$ has important consequences for low-energy observables. We demonstrate that intergenerational mass splitting and…
Motivated by the increasing precision of neutrino oscillation data, we study the corrections to the TM$_2$ neutrino mixing framework, emanating from $(1,2)$ sector of the charged lepton, for both the standard LMA and dark-LMA solutions. We…
Using the chargino-neutralino and slepton search results from the LHC in conjunction with the WMAP/PLANCK and $(g-2)_{\mu}$ data, we constrain several generic pMSSM models with decoupled strongly interacting sparticles, heavier Higgs bosons…
We propose a new possible explanation of the ATLAS di-boson excess: that it is due to heavy resonant slepton production, followed by decay into di-smuons. The smuon has a mass not too far from the W and Z masses, and so it is easily…
We investigate flavour violating decays of the long-lived lightest slepton and the tau lepton in the coannihilation region of the Minimal Supersymmetric Standard Model with a Seesaw mechanism to generate neutrino masses. We consider a…
A search for pair production of squarks or gluinos decaying via sleptons or weak bosons is reported. The search targets a final state with exactly two leptons with same-sign electric charge or at least three leptons without any charge…
A search for supersymmetry is presented in events with a single charged lepton, electron or muon, and multiple hadronic jets. The data correspond to an integrated luminosity of 138 fb$^{-1}$ of proton-proton collisions at a center-of-mass…
We examine the neutralino relic density in the presence of a light top squark, such as the one required for the realization of the electroweak baryogenesis mechanism, within the minimal supersymmetric standard model. We show that there are…
We present a supersymmetric extension of the Standard Model with a gauged SU(2) family symmetry for the leptons. It is shown that this family symmetry can be consistently broken at the TeV scale along with supersymmetry. If supersymmetry…
We perform an exhaustive scan of the allowed resonant production regime for sterile neutrino dark matter in order to improve constraints for dark matter structures which arise from the non-thermal sterile neutrino energy spectra.…
We use the Wilkinson Microwave Anisotropy Probe (WMAP) data on the spectrum of cosmic microwave background anisotropies to put constraints on the present amount of lepton asymmetry L, parameterized by the dimensionless chemical potential…
In the context of the seesaw mechanism, it is natural that the large solar and atmospheric neutrino mixing angles originate separately from large 2 by 2 mixings in the neutrino and charged-lepton sectors, respectively, and large mixing in…
We reexamine big bang nucleosynthesis with large-scale baryon density inhomogeneities when the length scale of the density fluctuations exceeds the neutron diffusion length ($\sim 10^7-10^8$ cm at BBN), and the amplitude of the fluctuations…