Related papers: Doubly Charged Fermions Bound States,Vector Bosons…
We analyse the possibility that, in two Higgs doublet models, one or more of the Higgs couplings to fermions or to gauge bosons change sign, relative to the respective Higgs Standard Model couplings. Possible sign changes in the coupling of…
We consider fermions on an extra dimensional interval. We find the boundary conditions at the ends of the interval that are consistent with the variational principle, and explain which ones arise in various physical circumstances. We apply…
We study theoretical and experimental constraints on electroweak theories including a new color-singlet and electrically-neutral gauge boson. We first note that the electric charges of the observed fermions imply that any such Z' boson may…
We consider a particular two-Higgs-doublet model with spontaneous CP violation, where two neutral Higgses have no definite CP properties and the third one is CP-even. In this model, as the parameter $\theta$ of CP violation increases, the…
It has been proposed that the observed diphoton excess at 750 GeV could be explained within the constrained minimal supersymmetric standard model via resonantly produced stop bound states. We reanalyze this scenario critically and extend…
We investigate here ground state properties of atoms, in which substitute fermions -- electrons by bosons, e.g. $\pi $ - meson. We perform some calculations in the frame of modified Hartree-Fock (HF) equation. The modification takes into…
We investigate the discovery prospects for a vector-like top partner ($T$) within the Type-II Two-Higgs-Doublet Model (2HDM-II) at future high-energy $\mu p$ colliders. The analysis focuses on the charged Higgs decay mode $\mu^+ p \to…
A search for pair-produced doubly charged Higgs bosons has been performed using the data collected by the DELPHI detector at LEP at centre-of-mass energies between 189 and 209 GeV. No excess is observed in the data with respect to the…
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…
The discovery of Standard-Model like Higgs at 125 GeV may raise more questions than the answers it provides. In particular, the hierarchy problem remains unsolved, and the Standard Model Higgs quartic self-coupling becomes negative below…
We discuss the hyperfine shifts of the Positronium levels in a relativistic framework, starting from a two fermion wave equation where, in addition to the Coulomb potential, the magnetic interaction between spins is described by a Breit…
Based on the two Higgs doublet model, we study the effect of Higgs-boson exchange on the (super)heavy quarkonium \bar QQ, which induces a strong attractive force between a (super)heavy quark Q and an antiquark \bar Q. An interesting…
We study models that interpolate between an elementary and a composite Higgs boson. Such models, arising in theories with new vector-like fermions with electro-weak quantum numbers and charged under a confining gauge interaction, are…
Exotic states in the charmonium family are systematically treated in the framework of simplest model with an effective coulomb-like interaction of heavy quark and antiquark in the presence of static excitation of quark-gluon modes…
A study of anomalous couplings of the Higgs boson to vector bosons and fermions is presented. The data were recorded by the CMS experiment at a center-of-mass energy of pp collisions at the LHC of 13 TeV and correspond to an integrated…
We point out that present experimental limits from searches for neutral Higgs bosons at LEP already imply stringent lower bounds on the mass of the charged Higgs boson in the Minimal Supersymmetric Standard Model (MSSM); these bounds are…
We study the discovery limits for doubly charged Higgs bosons, Delta^{--}, obtainable at the LEP e^+e^- collider. We expect that the LEP2 collaborations can rule out the existence of a doubly charged Higgs boson of mass below about 190 GeV…
In a recent measurement LHCb reported pronounced structures in the $J/\psi J/\psi$ spectrum. One of the various possible explanations of those is that they emerge from non-perturbative interactions of vector charmonia. It is thus important…
We determine the allowed parameter space of the CP-conserving two-Higgs-doublet model (2HDM) of type II with a softly broken Z_2 symmetry. Our analysis includes theoretical constraints from vacuum stability and perturbativity as well as…
We investigate the possible existence of the bound state in the system of three bosons interacting with each other via zero-radius potentials in two dimensions (it can be atoms confined in two dimensions or tri-exciton states in…