Related papers: $\mu^+e^- <---> \mu^- e^+$ Transitions via Neutral…
We revisit the process of inverse neutrino-less double beta decay (e e -> W W) at future linear colliders. The cases of Majorana neutrino and Higgs triplet exchange are considered. We also discuss the processes e mu -> W W and mu mu -> W W,…
We examine the muonium ($\mu ^+e^-$)-antimuonium ($\mu ^-e^+$) system in the models which accomodate the dilepton gauge bosons, and study their contributions to the ground state hyperfine splitting in ``muonium''. We also consider the…
Theoretical backgound for bileptonic gauge bosons is reviewed, both the SU(15) GUT model and the 3-3-1 model. Mass limits on bileptons are discussed coming from $e^+e^-$ scattering, polarized muon decay and muonium-antimuonium conversion.…
We show that the cross section of at least one of the s-channel processes e-e- (mu-mu-) --> l_i^- l_i^-, i=e,mu,tau, mediated by a doubly-charged scalar triplet bilepton is bounded from below and observable at a linear or muon collider if…
The doubly-charged scalar boson H^{--} is involved in several new physics models for generating neutrino masses. Depending on new physics models, H^{--} has the Yukawa interaction with a pair of left-handed charged leptons or a pair of…
We consider in the 3-3-1 model with heavy leptons the box contributions to the mass difference in $K$ and $B$ neutral mesons induced by neutral (pseudo)scalars, exotic charged quarks, singly and doubly charged scalar and gauge bosons. In…
Experiments such as MACS and the proposed MACE study muonium-antimuonium conversion by the energies of the final-state $e^\pm$. The $e^+$ and $e^-$ from an antimuonium decay tend to be non-relativistic and relativistic, respectively, and…
We extend the Standard Model gauge group by $U(1)_{L_e-L_\mu}$ and introduce two scalars, a doublet and a singlet, that are charged under this new group and have lepton flavour violating couplings. Since in this model $\mu \to e$ processes…
psi and Upsilon decays may be used to search for light neutral spin-1 or spin-0 bosons associated with a broken extra-U(1) symmetry, local or global, acting axially on quarks and leptons, as may be present in supersymmetric theories with a…
Global analysis of neutrino oscillation data slightly favors normal mass ordering. In this work, we investigate an extended scalar sector that naturally gives rise to a type I + II seesaw mechanism after spontaneous symmetry breaking and…
It is well known that at linear e^+e^-(e^-e^-) colliders using laser backscattering one can obtain colliding gamma-gamma, gamma-electron beams with energy and luminosity comparable to those in e^+e^- collisions. In this paper, it is…
We take an approach to the Lambda non-mesonic weak decay in nuclei based on the exchange of mesons. The one pion and one kaon exchange are considered, together with the exchange of two pions, either correlated, leading to an important…
A search for the lepton-flavor violating $\mu^{+}\rightarrow e^{+}\gamma$ decay using polarized muons is revisited in terms of suppression of the serious background arising from an accidental coincidence between a $e^{+}$ in the normal muon…
Theoretical backgound for bileptonic gauge bosons is reviewed, both the SU(15) GUT model and the 3-3-1 model. Then the mass limits for bileptons are discussed coming from $e^+e^-$ scattering, polarized muon decay and muonium-antimuonium…
Pseudoscalar and charged Higgs bosons production in the processes $\mu^+ \mu^-\to P^0_i Z^0$, $\mu^+\mu^- \to H^{\pm}W^{\mp}$ within the models with several Higgs doublets and singlets is considered.
Taking into account the exchange forces between protons of scalar, pseudoscalar, vector and axial vector type the cross sections of neutral and charged scalar mesons $a_0(980)$, $a_+(980)$, $f_0(980)$, $\sigma(600)$ production are…
Possible influence of the weak interaction on the $\mu^+ + \mu^- \to \mu^+ + \mu^- $ scattering and the $\mu^+ + \mu^- \to e^+ + e^- $ reaction, both through the neutral lepton currents and the charged ones (in the second order on weak…
We consider the contributions to the neutrinoless double beta decays in a $SU(3)_L\otimes U(1)_N$ electroweak model. We show that for a range of the parameters in the model there are diagrams involving vector-vector-scalar and trilinear…
We enumerate the simplest models that have baryon number violation at the classical level but do not give rise to proton decay. These models have scalar fields in two representations of SU(3) x SU(2) x U(1) and violate baryon number by two…
We show how light scalar fields can account for the discrepancy between the theoretical and observed values of the anomalous magnetic moment of the (anti)muon. When coupled to both matter and photons, light scalar fields induce a change of…