We study the electric dipole moments(EDM) of the neutron and the electron in the two-Higgs-doublet model, in the case that CP symmetry is violated maximally in the neutral Higgs sector. We take account of the Weinberg's operator O 3g = GGG as well as the operator O qg = qσGq for the neutron, and the Barr-Zee diagrams for the electron. It is found that the predicted neutron EDM could be considerably reduced by the destructive contribution of the two Higgs scalars to get the lower value than the experimental bound. As to the electron EDM, the predicted value is smaller in one order than the experimental one.

We introduce the flavor symmetry M × N ×D 4 into the SU(6)×SU(2) R string-inspired model. The cyclic group M and the dihedral group D 4 are R symmetries, while N is a non-R symmetry. By imposing the anomaly-free conditions on the model, we obtain a viable solution under many phenomenological constraints coming from the particle spectra. For the neutrino sector, we find a LMA-MSW solution but no SMA-MSW solution. The solution includes phenomenologically acceptable results concerning fermion masses and mixings and also concerning hierarchical energy scales including the GUT scale, the µ scale and the Majorana mass scale of R-handed neutrinos. * )

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The effect of the "chromo-electric" dipole moment on the electric dipole moment(EDM) of the neutron is studied in the two-Higgs-doublet model. The Weinberg's operator O 3g = GGG and the operator O qg = qσGq are both investigated in the cases of tan β ≫ 1, tan β ≪ 1 and tan β ≃ 1. The neutron EDM is considerably reduced due to the destructive contribution with two light Higgs scalars exchanges.

We give the detailed analyses for the gluonic-penguin effect on the Kπ and ππ decays of the B meson. In the standard model, it is shown that the ratio BR(B → Kπ)/BR(B → ππ) takes the value 0.5 ∼ 3.0 with the strongly depending on the CP violating phase φ and the KM matrix element |V ub |. We obtain the constraint on the form factor by using the experimental branching ratio. It is also found that, in the two-Higgs-doublet model, the charged Higgs contribution which could enhance the B → X s γ decay does not a sizable effect on our processes. The effect of the final state interaction on these processes is also discussed. Until now, the rare B decays have been intensively studied in the standpoint of the standard model(SM) and also beyond the standard model. Especially, b → sγ and b → sg sub-processes have attracted one's attention in the circumstance that the experimental evidence has been found in CLEO [1]. These decays, induced by the flavour changing neutral current, are controlled by the one-loop penguin operators which involve the important SM parameters such as the top-quark mass and the Kobayashi-Maskawa matrix elements V ts and V tb [2]. In our previous papers [3], we analyzed the inclusive decay B → X s γ and the exclusive decays B → K X γ, where K X denotes the meson states in the sq(q = u or d) system, as well as the exclusive decays B → K X φ by including the nonstandard physical effects due to the charged Higgs contributions in the two-Higgs-doublet model(THDM) [4][5]. In this paper, we study the B → Kπ and B → ππ decays, which are induced by both tree processes and gluonic penguin ones, in the SM model. Now we take into account QCD corrections, which were not included in the previous calculations[6], since the QCD corrections have been found to give the important contributions to the rare decays of the B meson. Recently, CLEO Collaboration reported the following experimental result [7]:

The decay B .... Xsy is analysed with the non•standard physical effects due to the charged Riggs contribution in the two•Riggs•doublet model. The hard Y emission of B•meson, being induced at one•loop level, is an important process to search for the non•standard contributions in the low energy region. It is shown that the charged Riggs contribution can provide sizable enhancements for the weak radiative B•decay compared to the standard model. It is also found that the process such as B .... K*(1410) + y has the largest fraction in the exclusive radiative decays, which amounts to almost 20%.

515Non-leptonic interactions in the current-current interaction are examined and criticized. By using a Born (factorization) approximation, it is concluded that the pure Lll = 3/2 process, i.e. the K+~n++no decay can be caused with strength about 20 times greater than the observed value and that the Lll=1/2 processes are, on the contrary, caused only partially (1/20......_1/50) irrespective of the process (hyperonic or mesonic) and of the presence or absence of parity conservation in the transition. It is also pointed out that this universal character of "theoretical" suppression for the Lll = 1/2 processes is due almost directly to the unwanted factor cos 2 8 sin 2 8. A new two-body interaction of leptons and a corresponding non-leptonic interaction with Lll = 1/2 is discussed.