The masses of charged leptons and quarks from superposition self-interference of their Dirac fields

Without Higgs field interaction, accurate pole mass values are obtained for the charged leptons and quarks from a Z₃-symmetric linear superposition self-interference of the Dirac fields in the effective free-field Lagrangian. The charged lepton and quark pole masses evidence the discrete Z₃ symmetry, the theoretical-experimental deviations δm/m are $ \mathcal{O} $ \mathcal{O} (10⁻⁵) for all three charged leptons, and the quark pole masses are in very satisfactory overall agreement with the experimental data.     

Isotopic effects in the muon transfer from pmu and dmu to heavier atoms

The results of accurate hyperspherical calculations of the muon-transfer rates from muonic protium and deuterium atoms to nitrogen, oxygen, and neon are reported. Very good agreement with measured rates is obtained and, for the three systems, the isotopic effect is perfectly reproduced. The transfer rate is higher for deuterium in the cases of nitrogen and neon due to constructive interferences between two transfer paths. The lower transfer rate for deuterium in the case of oxygen results from a large resonant contribution.     

Exotic decays of the muon and heavy leptons in gauge theories

We have studied the decay ?₁ → ?₂ + γ for arbitrary like charged spin $\text{1}\text{2}$ leptons in a manner which is applicable to a large class of models. Our computations assume that this process is induced by one loop diagrams. When the leading effect is cancelled by a leptonic G.I.M. mechanism, we find an extremely large enhancement of O(M_W⁴/M_L⁴) in Λ(μ^?→e^?+e⁺e^?)/Λ(μ^?→e^?+γ) if the intermediate lepton is charged.     

Branching fractions of tau leptons to three charged hadrons

From electron-positron collision data collected with the CLEO detector operating at Cornell Electron Storage Ring near sqrt[s]=10.6 GeV, improved measurements of the branching fractions for tau decays into three explicitly identified hadrons and a neutrino are presented as B(tau(-)-->pi(-)pi(+)pi(-)nu(tau))=(9.13+/-0.05+/-0.46)%, B(tau(-)-->K-pi(+)pi(-)nu(tau))=(3.84+/-0.14+/-0.38) x 10(-3), B(tau(-)-->K-K+pi(-)nu(tau))=(1.55+/-0.06+/-0.09) x 10(-3), and B(tau(-)-->K-K+K-nu(tau))<3.7 x 10(-5) at 90% C.L., where the uncertainties are statistical and systematic, respectively.     

Search for muon to electron neutrino oscillations

A search for _e and oscillations has been carried out with the CHARM II detector exposed to the CERN wide band neutrino beam. The data were collected over five years, alternating beams mainly composed of muon-neutrinos and muon-antineutrinos. The number of interactions of _e and observed is comparable with the number of events expected from flux calculations. For large squared mass differences the upper limits obtained on the mixing angle aresin ²2 < 9.4=" ·=">^–3 for oscillating to _e andsin ²2 < 4.8=" ·=">^–3 for to , at the 90% confidence level. Combining neutrino and antineutrino data the upper limit is 5.6 · 10^–3.On leave of absence from ITEP (Moscow)     

See-saw neutrino masses induced by a triplet of leptons

Neutrinos can acquire mass through the see-saw mechanism by extending the lepton sector of the Standard Model. The most generalSU(2) _L assignments allowed for the exotic leptons are the singlet and triplet representations. A model is constructed involving a triplet of exotic leptons. In this model lepton number is broken. Therefore lepton number violating processes, in particular those involving the lepton triplet, could provide distinctive experimental signatures.     

Pionic corrections to the masses of heavier hadrons in the bag model

The influence of pionic corrections to the masses of heavier hadrons is investigated in the cloudy bag model. After determining the bag parameters from ordinary baryons and mesons the heavier hadron mass spectrum is calculated. A sizable amount of pionic correction is observed which has improved the masses favourably.     

Bounds on the number and masses of quarks and leptons

We assume weak, electromagnetic and strong interactions to be asymptotically divergent, and to become strong at very large energies, of the order of the Plank mass. In this picture, the “low-energy” couplings (i.e. in the 10² GeV region) must be near the infrared stable point, and this allows us to put bounds on the number of elementary fermions (quarks and leptons). Similar assumptions on the Higgs couplings give bound on the fermion and on the Higgs boson masses. We consider the cases where weak and electromagnetic interactions are described by the gauge groups SU(2) ? U(1) or SU(2)_R ? U(1). The weak neutral current mixing angle is computed in both cases.     

Neutrino-lepton masses, Zee scalars, and muon g-2

Evidence for neutrino oscillations points to the existence of tiny but finite neutrino masses. Such masses may be naturally generated via radiative corrections in models, such as the Zee model, where a singlet Zee scalar plays a key role. We minimally extend the Zee model by including a right-handed singlet neutrino nu(R). The radiative Zee mechanism can be protected by a simple U(1)(X) symmetry involving only the nu(R) and a Zee scalar. We further construct a class of models with a single horizontal U(1)(FN) (à la Froggatt-Nielsen) such that the mass patterns of the neutrinos and leptons are naturally explained. We then analyze the muon anomalous magnetic moment (g(mu)-2) and the flavor changing mu-->egamma decay. The nu(R) interaction in our minimal extension is found to induce the BNL g(mu)-2 anomaly, with a light charged Zee scalar of mass 100-300 GeV.     

Comparison of electron and muon charged current neutrino and antineutrino interactions in a neonH2 mixture

From an exposure of the Fermilab 15 ft Neon(64 atomic %)H₂ filled bubble chamber to a single-horn-focussed $\text{ν}$ beam, we have found 60 e^?X and 35 e⁺X events, which we compare with 227 μ^?X and 202 μ⁺X events. No statistically significant departures from μ-e universality are seen in the shapes of various differential cross sections.     

Quark model predictions on the masses of heavier vector mesons

We use the quark model considerations of Federman, Rubinstein and Talmi and the relation (m _ψ/m _ϕ)≃(m _ϒ/m _ψ)≃(m _ϒ/m _ϒ) to compute the masses of beautiful and tasty vector mesons.     

Kinetic theory of ionization and electron capture by a charged impurity in a semiconductor

Inelastic electron-phonon scattering in which the electron is captured or escapes from the Coulomb field of an impurity is taken into account in the kinetic equation for conduction electrons. This scattering is shown to become strong in a certain energy range. In this range, the distribution functions of free and bound electrons are correlated in such a way that there is a balance between the trapping and ionization processes. The existence of a region of strong scattering is the decisive factor in calculating the experimentally measurable trapping and ionization coefficients, which enter into the electron balance equation.     

Search for lepton flavor violation in K+ decays into a charged pion and two leptons

A search for lepton flavor violating decays, K+ --> mu+ mu+ pi-, K+ --> e+ e+ pi-, K+ --> pi+ e+ mu-, K+ --> mu+ e+ pi-, and pi0 --> e+ mu-, was performed using the data collected in Experiment E865 at the Brookhaven Alternating Gradient Synchrotron. No signal was found in any of the decay modes. At the 90% confidence level, the branching ratios are less than 3.0x10(-9), 6.4x10(-10), 5. 2x10(-10), 5.0x10(-10), and 3.4x10(-9), respectively.