The differential cross section for the elastic scattering of protons by O¹⁸ has been measured for proton energies from 600 to 1450 keV at center-of-mass angles of 140.8° and 90.0°. Targets consisted of thin LiOH films on thin gold foils and BeO films on thick beryllium foils. The technique for the preparation of these thin O¹⁸ targets is described. Protons scattered elastically from O¹⁸ were selected by a 90°-magnetic spectrometer. Resonances were observed at 633, ∼680, ∼850, 987, 1169, 1239 and 1403 keV in proton energies, indicating the excitation of seven levels of the compound nucleus, F¹⁹. The resonance near 850 keV showed a marked anomaly with large width, and the resonance near 680 keV was a weakly excited one with large width. Other resonances had weakly excited anomalies with small widths.

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The excitation curve of the elastic scattering of protons by O¹⁸ is analyzed with a phase shift analysis based on the R-matrix dispersion theory. Resonance energy E_R(LAB), total angular momentum and parity Jπ, total resonance width Γ, proton and alpha particle partial widths Γ_p, Γ_α are determined and tabulated for seven resonance levels of the compound nucleus, F¹⁹ in the excitation energy range between 8.5–9.5 MeV.
The two-level approximation to the R matrix is applied to analyze the complicated shape of the excitation curve due to the two interfering broad levels of the same spin and parity, 680 and 846 keV resonances. The whole excitation curve in the proton energy range between 600 and 1450 keV except at small resonance anomalies is well reproduced by using the resonance phase shift due to the above-mentioned two 1⁄2+ resonances, the hard sphere scattering phase shift of s and p wave, and the Coulomb scattering amplitude.
All other weakly excited resonances with small level widths are analyzed by the one-level approximation assuming that they are superposed on the general trend of the excitation curve. Each resonance parameter is uniquely determined.
A method of treating the finite energy resolution due to the target thickness and the beam energy spread is discussed.

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The cut-off rigidity depends not only on the geomagnetic latitude but also on the geomagnetic longitude, therefore the energy balance of cosmic rays at four stations, i. e. Saskatoon (geomagnetic latitude 60.5°, geomagnetic longitude 311.9°), Minneapolis (55.2°, 330.9°), San Angelo (41.3°, 317.3°), and Guam (3.6°, 212.9°) has been analyzed. Adopting the revised energy spectrum and the altitude variations of intensities and taking account of the underestimation of energy dissipated by the nuclear disintegration, there is a good agreement between the incident energy and the energy dissipated in the atmosphere at any place.

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The magnetoresistance of n-type germanium has been measured at 300°K, 77°K and 4.2°K with donor concentration in the range 10¹⁷ cm⁻³ to 2×10¹⁹ cm⁻³. The magnetoresistance symmetry relation is obeyed in all measured samples at 300°K within the experimental error. The measurement at 77°K shows definite deviation from the symmetry relation in samples with high donor concentration. The behavior of resistance change under the magnetic field at 4.2°K depends on whether donor concentration lies in impurity conduction range or in metallic conduction range. In metallic conduction range the observed magnetoresistance Δρ⁄ρ has been separated in to two components, one being positive and proportional to the square of magnetic field and the other being negative and showing saturation at a relatively low magnetic field. The former has been compared with the magnetoresistance observed at 77°K.

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Uniaxial ferromagnetic anisotropies induced by mechanical cold rolling were measured as functions of a thickness reduction and a size of ferromagnetic precipitates at 77°K and 300°K on the Cu-Co alloys containing ca. 2 and 3 wt% Co which were aged at 750°C. The induced anisotropy energy was found experimentally to be expressed as E_u=−K_ucos²θ, where θ is the angle between the roll direction and the measuring field direction in the roll plane. The maximum value of the observed anisotropy constant K_u was 1.3×10⁵ ergs per cc. The magnitude of the anisotropy and its dependence on the roll reduction can be explained in terms of shape anisotropy of precipitates.
Two effects of deformation on the induced anisotropy were observed: the first one is explained as the result of change in precipitate shape after homogeneous and inhomogeneous deformation, and the other concerns a superparamagnetic behavior of precipitate particles caused by fine division of particles caused by inhomogeneous deformation.

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The electrical and optical properties of n-type CdTe single crystals containing In or Ga were investigated. The maximum of photoconductivity was given by the expression (1.57–4.4×10⁻⁴T) ev in terms of photon energy and agreed with the energy at the absorption edge. The ionization energies of both In and Ga donors were about 0.04 ev. The Hall mobilities of conduction electrons were about 800 cm²/volt sec. at room temperature. The magnetoresistive effects were investigated in the range of the low magnetic field. This investigation led to the conclusion that the structure of the conduction band might be approximated by the model of four or eight energy spheroids, of which the symmetrical axes coincided with the eight [111] directions.

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Enhanced nuclear magnetic resonance of Fe⁵⁷ in yttrium iron garnet, nine substituted iron garnets, magnetite and hematite were observed. In garnets two resonances for two positions of Fe³⁺ were measured. Resonance frequencies in rare earth substituted iron garnets do not so much differ from the resonance frequencies of Fe⁵⁷ in yttrium iron garnet. If one compares relatively accurate resonance frequencies observed in various garnets, it is clearly seen that the effective magnetic field at the nucleus is proportionally increased with their crystal lattice parameters. The fractional variation of this field over all garnets is within four percents on both sites.
The resonance of Fe⁵⁷ in magnetite is also enhanced by domain wall excitation. Two resonance frequencies corresponding to octahedral and tetrahedral sites were observed at room temperature. Below the transition temperature only one broad resonance was confirmed. A resonance of Fe⁵⁷ corresponding for Fe³⁺ in hematite was observed on sample containing small amount of magnetite.

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From the assumption that the fluctuations of the local shear stress displaces a length of the dislocation for unit distance of the Peierls potential, the activation energy of Bordoni peak is derived for the crystals of relatively large Peierls stress and of low dislocation density. For the crystals of the contrary case, it is pointed out that the activation energy of Bordoni peak is affected by the dislocation density. The relations between the activation energies of Bordoni peak and Peierls stress are discussed on various crystals. The Peierls stress of LiF crystal, 10 kg/mm², is obtained.

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The frequency dependent non-ohmic behavior of conduction electrons in the static magnetic field, under the influence of applied microwave field, is investigated. As the electrons become hotter, the electron acoustical-phonon interaction becomes larger and the relaxation time shorter, so that the half-width of the cyclotron resonance line (ωτ)⁻¹ grows up. The result of the calculation shows that the relation (ωτ)⁻¹∝(P⁄m_x)^1⁄n holds, where P denotes the microwave power. In the case where practically only spontaneous emission of phonons takes place, n takes the one extreme value 2.5, while it does the other extreme value 4 in the case where both emission and absorption of phonons occur in sufficient magnitudes.
Evidently, the average electron energy ε_e is a function of ω_c–ω for a given power. Since the relaxation time depends on ε_e, it is a function of ω_c–ω. Hence the absorption line deviates from the ordinary Lorentzian curve in which the relaxation time is taken constant throughout the range of ω_c. These results are in good agreement with the observations.

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This paper deals with the steady two-dimensional channel flows of an incompressible perfect fluid with small electric conductivity in the presence of nonuniform magnetic fields generated by a system of electric currents and magnetic poles. The flow and the magnetic fields are calculated for small values of electric conductivity of the fluid. The velocity distribution is found, with in the order of our approximation, to depend only on the distribution of the magnitude of the magnetic field. The numerical calculations are performed for one case of the geometrical parameter which represents the position of the currents or of the magnetic poles, and the results are shown graphically. The analytical expressions for the pressure difference between infinities down- and up-stream and the velocity distribution at the infinity downstream also presented.

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The Motion of a cylindrical plasma-layer caused by a magnetic field induced by currents flowing through the plasma is investigated by the use of the two-fluid model. The motions of electron- and ion-layers are considered individually. The phenomena are classified into two types. In the first type, the electron-layer which is driven by the Lorentz force to the center axis of the cylinder, is separated rapidly from the ion-layer and a rather wide space with the electric field is formed between the two layers. In the other type, the electron-layer is oscillating about the ion-layer which is driven slowly to the axis of symmetry. The numerical calculations are carried out for typical examples of the two types.

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The interaction between the two-dimensional flow past a thin airfoil and the magnetic field perpendicular to the plane of flow is studied on the basis of the fundamental equations recently derived by the author (J. Phys. Soc. Japan 15 (1960) 1523). When the magnetic Reynolds number is infinite, the space current pattern is constructed conveniently with a stream function. When the magnetic interaction is very weak, the situation is similar to that of the aligned field case except for the wake running rearward in the subsonic flow.

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The performance of a semicircular magnetic spectrograph and spectrometer has been studied from the point of view of the Fourier-analysis. The approximate expression for the intensity distribution of the image is given and the spatial frequency response has been calculated as in the field of lens optics. The applications of the theory are described for (i) determination of the optimum condition of experiments (ii) evaluation of the performance of spectroscope (iii) estimation of the input spectrum through the output and for (iv) measuring intervals for discrete recording. The approach described here may be useful for the comparison of performance of various different types of magnetic spectroscopes and may give the first step to introduce information theory into the problem of magnetic spectroscopy.

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Classical methods are applied to treat the free symmetrical vibrations of a circular membrane consisting of any number of concentric parts from different materials. Several new results are obtained.

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