The reaction, γ+d→d+π⁰, has been used to measure the isotopic vector part of the photopion production amplitude from nucleons around the second resonance. The differential cross sections have been measured at 57.6° (lab) for E_γ=500∼700 MeV. The momentum of recoil deuterons was analyzed with a magnet and their flight time was measured with a time-to-pulse height converter, to discriminate deuterons from protons and pions. The measured cross sections were analyzed in terms of the π–N phase shifts basing on the impulse approximation. The s₃–, s₁–, p₃₃–, p₁₁– and d₁₃– phase shifts are included in this analysis. The measured cross sections are in fairly good agreement with the calculation. However, the cross sections calculated in the absence of the d₁₃–wave are smaller by about 40% than the measured ones. The results of analysis are consistent with the assumption that the d₁₃–wave amplitude of photoproduction from free nucleons is an isotopic vector.

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The phase shift analysis of the proton-He⁴ elastic scattering at 29, 40 and 55 MeV is performed. The opening of inelastic channels are taken into consideration by indroducing inelastic parameters, that is, by using the complex phase shifts. Our results are consistent with those derived from the meson theoretical nuclear forces (K. N. O. S. phase shifts). The phase shifts of proton-He⁴ scattering show strong energy and state dependences. D-wave phase shifts are negative in the low energy region and the l-s splitting in the D-state shows the inverted doublet splitting up to 55 MeV.

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The phenomenological theory of the phase transitions in NaNO₂ proposed by Yamada et al. is extended to include three dimensional lattice strain. The calculated temperature dependence of the ordering parameters and dielectric susceptibility represent fairly well the experimental data. The effects of the bias field and the pressure are also calculated and the results prove to be satisfactory. The electrostrictive coefficients are estimated, and a simple consideration is made on the origin of the sign reversal of the electrostrictive coefficients during the ferroelectric-to-sinusoidal phase transition and also of the large temperature dependence of Q₂₂ and Q₃₂.

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Temperature dependence of the dielectric constant ε₂₂ of NaNO₂ was measured at various hydrostatic pressures up to about 10 kbar. Both the Curie temperature T_f and the Néel temperature T_N increase with increasing pressure. The initial slopes of the transition temperature vs pressure curves are given as:
dT_N⁄dp=5.6×10⁻³degbar⁻¹,
dT_f⁄dp=4.9×10⁻³degbar⁻¹,
respectively. The obtained results are compared with the data of specific heat and dilatation experiment. The phenomenological discussion of one of the authors (K. G.) is shown to explain fairly well the experimental results.

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Spectral behaviour of the Faraday rotation at a resonance frequency is investigated from the view point of the quantum theory of radiation field. The theory is applied to the case of the singlet-triplet transitions in hydrocarbons. The rotational power is obtained in an explicit form for this case, and the spectral curves are shown to illustrate the characteristic dependence of the Verdet constant on the field strength and the damping of resonating molecular levels. The results are used to explain Shashoua’s experimental results which have suggested typical aspects of the rotation spectra in unsaturated hydrocarbons, corresponding to the wave length of the singlet-triplet transitions of the molecules.

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Gamma-irradiation of ferroelectric lithium tri-hydrogen selenite has been shown to produce two kinds of paramagnetic species exhibiting the anomalous anisotropies of g-tensors at room temperature. These species show no hyperfine structure.
Electron spin resonance spectra and optical absorption spectra suggest that the crystal contains ionic molecule (SeO₃)⁻ as the paramagnetic species. This type of molecule has been identified ²A′ as the ground state with symmetry of C_s. The anomalous anisotropies of g-tensors are explained by the admixture of excited states into the ground state. It is interpreted that the spectral lines corresponding to the two kinds of species are due to the existence of paramagnetic molecules (SeO₃)⁻ which are reduced to (SeO₃)_I²⁻ and (SeO₃)_II²⁻ in the crystal lattice.
The temperature dependence of g-tensors suggests that molecular structure of paramagnetic species varies somewhat at temperatures slightly below the melting point.

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The strain dependence of impurity conductivity has been measured in compensated p-type germanium containing 5×10¹⁵ to 1.2×10¹⁶ impurity atoms/c.c. using large uniaxial compression. For both ⟨100⟩ and ⟨111⟩ compression the ground state orbital of acceptor was found to have an ellipsoidal envelope along the stress direction and was enlarged. Impurity resistivity decreases linearly in a log-log plot of the resistivity versus the inverse strain when the stress is large enough to split off the degenerated valence bands.
The decrease of resistivity shows a large difference between the cases of ⟨100⟩ and ⟨111⟩ stress, whereas the difference by the impurity concentration is small.
Some clues for the mechanism of impurity conduction in the intermediate impurity concentration region may be found in this experiment.

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The conventional transport properties—the Hall coefficient, the electrical resistivity and the thermoelectric power in five indium-rich solid solutions, In-Cd, In-Sn, In-Hg, In-Tl and In-Pb were measured in the range of 0∼5 and 0∼10 at. % of solute at 110°C. The electrical resistivity of these alloys varies linearly with the solute concentration in the range of measurement.
The Hall coefficients are small negative value compared with other ordinary metals such as copper, and decrease linearly with the solute concentration except In-Cd system, for which a minimum is found at about 5 at. % Cd.
The thermoelectric power of these alloys also decreases from a small positive value in indium (+0.82 μV/deg) toward the negative direction, and there is a minimum for In-Cd system at 5 at. % Cd.
The small value of the Hall coefficients, the linear changes of them, and the fall of the thermoelectric power with the solute concentration can be explained by assuming the existence of two types of carriers; one is electron-like and the other is hole-like. In order to explain the appearance of the minimum of the Hall coefficient and the thermoelectric power observed in In-Cd system, an assumption about the overlap of the Fermi surface across the boundary plane of the Brillouin zone is suggested .

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The line shape change of nuclear magnetic resonance dispersion at high r. f. field, γH₁>>ω_m, was discussed as a function of modulation frequency ω_m and spin-lattice relaxation time. The expression of first derivative line shape of nuclear magnetic resonance dispersion was derivated after Redfield’s theory.
New convenient method to estimate spin-lattice relaxation time of material was proposed from the analysis of the dispersion line shape at a proper modulation frequency and slow scanning. And it was also shown that the dispersion line shape was not so sensitive to the circumstances of resonant nuclei as in the case of absorption, such as Lorentzian or Gaussian.
Experiments was done for a simplest case of T₁=T₂, and the agreement with the theory was satisfactory.

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Electron drift velocity and mobility InSb are calculated from the results of pulsed measurements of the conductivity and Hall effect in the temperature range from 80°K to 200°K. Above a critical field where impact ionization set in, electron drift velocity decreases with increasing electric field. This increase in electron collision frequency or reciprocal mobility due to electrical breakdown was found to be proportional to the first power of increased hole density for n-type materials. This fact can be interpreted as the results of electron-hole scattering. The discrepancy between the results and theoretical expression of electron-hole scattering, namely Brooks-Herring formula, is removed in n-type materials when carrier drag effect is taken into accout. The disagreement, however, remains for p-type materials. Magnetic field dependence of electron mobility and effects of minority carrier injection in high electric fields are also studied.

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The luminescent characteristics were investigated with the lead- and the tin-activated zinc sulphide phosphors. The bright orange-yellow and orange-red emissions were observed with the lead- and the tin-activated phosphors, respectively, when the phosphors were obtained in a controlled sulphurizing atmosphere. The preparative conditions for obtaining intense luminescent emissions were studied. The emission and the excitation spectra for these phosphors were measured and were found to be well described with Gaussian curves. For the yellow luminescence in the lead-activated phosphors the temperature dependences of emission and of excitation band-widths were studied and configuration coordinate curves were calculated. It was concluded that the luminescent centers responsible for these emissions are tetravalent impurity ions substituted at zinc sites and not associated with zinc vacancies. The electron transfer from neighboring sulphur ions was proposed as a possible mechanism for the luminescent process.

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Valence electrons of the boron atom substituting for carbon in 6H silicon carbide have been studied, for the purpose to elucidate the results of electron spin resonance experiment by Woodbury and Ludwig. A theoretical predict has been presented on the basis of tight binding approximation. Partial ionicity of the B-Si bond where the boron atom is positive has been proposed as an origin of small ¹¹B hyperfine interaction compared with ²⁹Si superhyperfine interaction. The opposite signs in the hyperfine constants A and B observed in one spectrum (called I) have been interpreted in terms of a weak trigonal field. Its potential for electron is lower in the direction of the B-Si bond parallel to the c axis. Such a trigonal field is demonstrated in the boron center occupying the site 9d, to which the spectrum I is likely to be assigned. The calculation has also predicted the g_|| value to be identical to the free spin’s and the g_⊥ value to be slightly larger than it, in good agreement with the values observed in the spectrum I. Similar argument, however, does not apply in the g factors of the other two spectra (called II and III), for which higher order of approximation may be necessary.

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A general discussion has been made on the factors which determine the type, number and size of secondary defects which are formed by vacancies in quenched face-centered cubic metals. A method of analysis, which uses the positive (growth) and negative (shrink) reaction ratios, has been introduced. This method is especially applicable for the analysis of the formation of such secondary defects that have weak bindings to vacancies at the initial stage of their formation.
The existence of the large negative reaction during a wide range of nucleation and growth of faulted dislocation loops in quenched aluminum (the existence of large clusters which are apt to maintain equilibrium with migrating defects) is confirmed experimentally, and the formation of the loop is analyzed by the method introduced. Nucleation and growth of perfect dislocation loops, double layer faulted dislocation loops, voids and stacking fault tetrahedra are also discussed.

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The time-dependent theory of the tunneling problem is developed for the ideal semiconductor junction with an inhomogeneous electric field. It is shown that the tunneling probability of Fredkin and Wannier type can be derived from the rigorous formula for transition probability between an incident and an outgoing wave packet.
The tunneling probability of the final form is obtained by using the difference equation and the variation principle of Lippmann and Schwinger. The weak field approximation hitherto supposed is not used but a strong field approximation is taken on the junction potential. The result obtained resembles that of a free electron tunneling through one-dimensional barrier. The time-independent formulation is added in Appendix.

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By using the electronic structure of the Fermi surfaces of nickel, which was evaluated by the authors, and the observed phonon spectrum, the matrix elements of the electron-phonon interaction in nickel are calculated. Then, the absolute value of the electrical resistance is evaluated at 80°K and 1000°K without any adjustable parameters. The calculated value of the resistance is about three times larger than the observed one, without considering screening effects of electrons on the electron-phonon interaction. At low temperatures below 10°K the observed resistance is proportional to T². Here, it is proposed that the conduction electron is scattered to the d-bands with opposite spin orientation by the exchange interaction. This type of interaction gives a resistance proportional to T². Further, the resistance due to this mechanism is roughly estimated. The result seems to be reasonable, so far as the order of the magnitude is concerned.

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Evaporated single crystal films of gold-palladium alloys were studied by electron diffraction, compositions of the alloys widely ranging from 10 to 60 atomic per cent palladium. An ordered phase with the Cu₃Au type structure was found to exist in the region of composition around 25 atomic per cent palladium. The order-disorder transformation seems to occur at about 850°C in the films of this composition range.

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The piezoelectric modulus d₃₃, electromechanical coupling factor k₃₃ and elastic compliance coefficients s₃₃^D, s₃₃^E of SbSI have been determined by measuring the resonant and anti-resonant frequencies on single crystals of 3 mm in length and 0.7×0.7 mm² in cross section. The d₃₃ has been found to show the highest value of 10⁻⁴ cgsesu near the Curie point. The k₃₃ shows an extremely high value of 90% just below the Curie point and nearly constant value of about 75∼85% in the range of temperature below 0°C.

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Earlier workers observed that in the initial stages of room-temperature F-band irradiation of additively-colored, freshly-quenched alkali halide crystals a low energy broadening of the F band appeared. Here this broadening in KCl was measured and similar results for two very different sodium concentrations were obtained. This indicates that sodium F_A centers are not responsible for the effect. The “resonance broadening” due to the dipolar interaction of two F centers was calculated. It was found that this mechanism could account for the observed phenomenon if most of the F centers were about 3 nearest neighbors apart, or if 5% of them were about 2 nearest neighbors apart. Published experimental results indicate that in the early stages of irradiation few of the F centers are this close together, although a number as small as 5% is not necessarily ruled out. Other possible explanations of the experimental results are discussed.

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Band structure of metallic copper and nickel are calculated by a self-consistent procedure. A self-consistent potential is constructed by a modified Hartree-Fock-Slater approximation. The general properties of the bands are in good agreement with those obtained previously. The band structure of Ni in a ferromagnetic state is evaluated. The exchange splitting energy for d-like electrons is estimated as about 0.07 Ry, while for s- and p-like electrons as 0.015 Ry. The theory suggests that there exists a neck on the Fermi surfaces of both up- and down-spin electron bands.

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The distribution of the high plasma density along the length of a long semiconductor rod of small radius is discussed theoretically, introducing the surface recombination rate. Assumptions used here are that there exists a high level injection only at one end of the semiconductor rod, that the diffusion current is much smaller than the drift current and that the radius of sample is much smaller than twice the diffusion length in the bulk of the sample with relatively small surface recombination velocity. The theory is in fairly good agreement with the experiments.

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Electromagnetic wave propagation through a semiconductor with a non-uniform density distribution in transverse magnetic fields has been studied theoretically. It is shown that waves in the UHF band will propagate in only one direction, determined by the directions of the external magnetic field and the density gradient. The experimental conditions required to observe such a wave are given.

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Spectroscopic measurements of the electron temperatures T_e, have been made for the atmospheric argon plasmas seeded with sodium vapors at gas temperatures above 2000°C. The relationship between T_e and current density j has also been obtained. The values of j calculated from the measured T_e and seeding ratios agree well with the experimental values. These results indicate that an electron energy equation containing radiation loss terms is applicable to the estimation of the non-equilibrium ionization in the working plasmas for the magnetoplasmadynamic power generating systems.

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The response of a plasma in a magnetic field to an electric field oscillating with frequencies higher than the collision frequency is investigated in the unified theory without any cut-off procedure. A general form of the electric current due to the applied field is obtained and the conductivity is calculated. With use of the connection formula the exact Coulomb logarithms are obtained. The Coulomb logarithm in the components of the conductivity perpendicular to the magnetic field differs from the one in the parallel component. Some limiting cases are treated in detail.

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The instability of a plane boundary of Plasma supported under gravity by a magnetic field is investigated in the first order orbit theory taking into account the collisions between charged and neutral particles, where the collision frequency is assumed to be small as compared with the Larmor frequency. It is demonstrated that the instability growth rate may be suppressed by collisions of ions with neutral particles, and the physical mechanism of the stabilization is the “discharge” of surface charges as a result of the collisional drift motion of ions which takes place across the magnetic field in the direction of the produced electric field. The results are applied to the slow theta-pinch experiments in order to understand the observation of no Rayleigh-Taylor instabilities in the contraction stage of the slow theta-pinch.

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Natural convection of an electrically conducting fluid past a vertical porous flat plate in the presence of a uniform transverse magnetic field is discussed when the plate is subjected to uniform suction or injection. It is found that for a fixed value of suction or injection both skin friction and rate of heat transfer decrease with increase in magnetic field while for a fixed magnetic field the wall shear and the heat transfer coefficient decrease with injection and increase with suction.

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The problem considered is the steady flow of an incompressible viscous fluid through the space between two rotating coaxial cones with porous walls. In the case where the boundaries of the conical channel are α=20° and β=70°, the effect of the injection at the inner and suction at the outer porous walls on the radial flow is calculated. When this effect increases, the back-flow is set up in the region nearer to the inner cone: whereas the flow velocity in the region nearer to the outer cone is increased. Furthermore, it is found that the flow velocity depends linearly on the effect of the injection and suction.

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Non-ohmic behavior in CdS associated with ultrasonic amplification was investigated. The threshold fields for the departures from Ohm’s law depend upon the crystal length and decrease with increasing conductivity.
The buildup time of acoustoelectric current decreases with increasing conductivity or applied fields. The buildup time for high conductivity samples is independent of crystal length and that for low conductivity depends upon crystal length.
The field distribution is approximately uniform in ohmic region, but fields near positive electrode become higher as applied fields increase above threshold.
Additional attenuation of transmitted microwave power (9.6 Gc) was observed when the main d.c. pulse along CdS was in saturation region.
Electron drift mobility μ in the temperature range 300°K∼120°K is estimated from threshold fields E_th by using the relation μE_th=v_s (v_s: sound velocity).
At low temperature anomalous current-voltage characteristics were observed; steady-state current decreases at fields just above threshold and then increases again with increasing fields.

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