Related papers: Allowable Low-Energy E_6 Subgroups from Leptogenes…
We have developed a concept of parallel existence of the ordinary (O) and hidden (H) worlds with a superstring-inspired E_6 unification, broken at the early stage of the Universe into SO(10) X U(1) - in the O-world, and SU(6)' X SU(2)' - in…
Mechanism for generation of suppressed neutrino masses, within low scale theories, is considered. The mechanism do not have extradimensional nature and is realized through extended $SU(2)_L$ scalar multiplets. Latters, in some cases, are…
Massive neutrino is an evidence of new physics beyond the Standard Model. One of the well motivated new physics scenarios is a model with gauged lepton flavor symmetry. We investigate neutrino properties in the minimal…
If $R$-parity is not conserved, the SUSY-threshold production process $e^+e^- \to \chi_1^0\chi_1^0$ could be detectable with relatively low luminosity. Hence an interesting mass range for the lightest SUSY particle $\chi_1^0$ could be…
We consider the possibility of grand unification of the $\mathrm{ SU(3)_c \otimes SU(3)_L \otimes U(1)_X}$ model in an SU(6) gauge unification group. Two possibilities arise. Unlike other conventional grand unified theories, in SU(6) one…
We consider a flavoured $B-L$ gauge symmetry under which only the third generation fermions are charged. Such a symmetry can survive at low energies (~TeV) while still allowing for two superheavy right-handed neutrinos, consistent with…
The scotogenic type I and type III seesaw models are good candidates to explain the existence of neutrino masses and dark matter simultaneously. However, since triplet fermions have SU(2) gauge interaction, they cannot be out of equilibrium…
We study thermal leptogenesis induced by decays of a scalar SU(2)_L triplet. Despite the presence of gauge interactions, unexpected features of the Boltzmann equations make the efficiency close to maximal in most of the parameter space. We…
We reexamine lepton mixing in gauge models by considering two theories within the type I seesaw mechanism, the Extended Standard Model, i.e. SU(2)_L \times U(1)_Y with singlet right-handed heavy neutrinos, and the Left-Right Model SU(2)_L x…
We investigate thermal leptogenesis within a supersymmetric grand unified theory (SUSY GUT) based on the $SO(10) \times U(1)_A$ symmetry, where both the doublet--triplet splitting problem and the unrealistic Yukawa relations are resolved…
We discuss extension of the electroweak gauge group to $SU(3)_L \times SU(3)_R \times U(1)_{XL} \times U(1)_{XR}$. This adds new leptons to the familiar 331-model. The explanation for three light quark-lepton families remains but new…
The alternative $[SU(3)]^4$ model of leptonic color and dark matter is discussed. It unifies at $M_U \sim 10^{14}$ GeV and has the low-energy subgroup $SU(3)_q \times SU(2)_l \times SU(2)_L \times SU(2)_R \times U(1)_X$ with $(u,h)_R$…
We consider a low-energy supersymmetric scenario in which the effects of heavy supersymmetric interactions are included in a model-independent manner through a series of supersymmetric SU(3)_C*SU(2)_L*U(1)_Y invariant operators; we…
We construct a full left-right model for the electroweak interactions based on the $SU(3)_{L}\otimes SU(3)_{R}\otimes U(1)_{X}$ gauge symmetry. The fermion content of the model is such that anomaly cancellation restricts the number of…
We discuss a simple non-supersymmetric model based on the electroweak gauge group $SU(2)_L\times SU(2)^\prime\times U(1)_{B-L}$ where the lightest of the right-handed neutrinos, which are part of the leptonic doublet of $SU(2)^\prime$, play…
We review the non-supersymmetric (Extended) Left-Right Symmetric Models (LRSM) and low energy $E_6$-based models to investigate if they can explain both the recently detected excess $eejj$ signal at CMS and leptogenesis. The $eejj$ excess…
The problem of testing leptogenesis from low energy experiments is discussed following three different perspectives. Firstly, we review the prospects that from low energy experiments we could reconstruct the neutrino Yukawa coupling matrix…
We review the status of thermal leptogenesis in the minimal $SU(5)\times U(1)$ and $SO(10)$ unified models under the assumption that the leptonic asymmetry generated in the out-of-equilibrium decays of heavy Majorana neutrinos (and its…
We investigate the possibility of low-scale leptogenesis in the minimal supersymmetric standard model extended with right handed (s)neutrinos. We demonstrate that successful leptogenesis can be easily achieved at a scale as low as ~ TeV…
Leptogenesis appears to be a viable alternative to account for the baryon asymmetry of the universe through baryogenesis. In this context, we consider a scenario in which the standard model is extended with $S_3$ and $Z_2$ symmetry in…