Hiroshi Konashi

The one-gluon exchange effects to gAgV of baryon semileptonic decay

Abstract The one-gluon exchange effects to g A g V of the processes, B → B′ + l + v l are investigated in the MIT bag model. Their contributions are rather consistent with the data.

Nonleptonic Decays of Charmed Mesons

Abstract The experimental data on the relative rates in charmed meson decays are explained in terms of the Kobayashi-Maskawa mixing matrix of the six-quark model and the dipole type form factors for mesons.

Neutral-current effect in lepton pair production with polarized photons

Abstract We have investigated the parity-violating asymmetry for the lepton pair production with circularly polarized photons. Numerical calculations are given in the Weinberg-Salam model.

Neutral-Current Effects in Electron-Polarized Deuteron Scattering

The weak neutral·current effects in electron-polarized deuteron scattering are investigated in the Weinberg-Salam, SU(3)x UO) and SU(2hxSU(2)RX UO) gauge models. We derive the parity-violating asymmetry for the scattered electron. It is expressed in terms of wellknown electromagnetic and weak form factors of the nucleon. The asymmetries are expected to be of the order of 1O~6 and 1O~5 at the incident electron energy of 0.5 GeV and 2 GeV for each gauge model. The experiment at 0.5 Ge V gives the strong constraints on these gauge models and at 2 Ge V may be useful to discriminate them.

Neutrino pair production in e+e- collision; a method for neutrino distinction and family counting

SummaryWe investigate the following process; e+ + e- → ν+ν and give the total cross-sections for the case that the final neutrinos are Dirac or Majorana particles. We propose such a reaction as a method for distinguishing between these types of neutrinos and counting the number of families.

Parity-Violating Asymmetry in Lepton Pair Production with Circularly Polarized Photons

The neutral-current effects in the lepton pair production with circularly polarized photon beams have been investigated in unified gauge theories. We derive the parity-violating asymmetry of leptons produced by right- and left-handed photons. Numerical calculations are given for the proton and isoscalar targets in the Weinberg-Salam model. The asymmetry is shown as a function of the lepton energy in some kinematical configurations. We find the parity-violating effects are of the order of w-• for the incident photon energy of 20 Ge V.