The ⁵⁸Ni(d, t)⁵⁷Ni reaction is studied at E_d=23.97 MeV. Spectroscopic factors are obtained from DWBA analysis of angular distributions. Form factors from conventional well-depth description and from well-radius description are used. Results are consistent with those from the 52 MeV (p, d) experiment.

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Elastic Scattering of ¹⁶O ions on ⁹Be has been measured at energies near and above the Coulomb barrier. Angular distributions were calculated with the optical model with Woods-Saxon potential. Igo ambiguities were shown in these analyses. This suggests that there will be a strong absorption situation in the scattering of ¹⁶O on ⁹Be in this energy region. Strong absorption radii were extracted with consideration of the nuclear interaction at the surface.

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We propose to define a “practical” critical energy E_c as the energy at which the experimental detection efficiency of α-particles with celluloid SSTD is just 50 per cent. The values of E_c at an incident angle θ=45° were measured as functions of etching time. It was also observed that the values of E_c were increased by appropriate irradiation with ultraviolet light of 2537Å. An “intrinsic” critical energy ε_c(θ) is proposed to be defined as the energy at which the etching rate along the track V_T is equal to V_G⁄sinθ, where V_G is the etching rate of the detector material itself. The value of ε_c(90°) was deduced from the observed values of E_c(45°) to be ε_c(90°)=2.72±0.10 MeV, being independent of the sorts of celluloid tested (Daicel and another one) and of UV irradiation.

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A simple consistent picture is presented for the newly discovered particles ψ(3105) and ψ′(3695) as well as for the baryon ℵ(2015) reported seven years ago. It also resolves the so-called “energy crisis”.

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A generalized Fokker-Planck equation, which describes the relaxation process of a quantal spin, is obtained on the basis of a microscopic theory. In the high-temperature, classical and usual Fokker-Planck limits, the equation derived by Kubo and Hashitsume using a phenomenological theory is justified.

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A theory is formulated for the ground state of a degenerate Bose fluid in thermal equilibrium. The fluctuations in the condensate are treated in terms of the fluctuation operators C=a₀−α, and thir conjugate, α₀ being the annihilation operator for the zero momentum state and the order parameter α the quasiaverage of α₀. The superfluid ground state is viewed as energy lowering by coherent excitations. The coherent state is defined in terms of the normal modes in the superfluid phase. The superfluid ground state is not the ground state of the type studied by Glassgold and Sauermann.

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It is intended to investigate succeeding phase transitions in a crystalline substance not individually or separately but collectively or in recognition of them as a set of interrelated ones. Of conceivable various sequences or systems of transitions, the most fundamental are homophone systems that are each generated by one prototypic phase and one set of degenerate soft modes. The structure of a general homophone system is analysed with the introduction of “the rank of a ferroic phase” and a few other basic concepts.

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The γ ray Compton profiles along the two major axes [100] and [110] have been measured on niobium single crystals with a pure Ge solid-state detector. The measured profiles were fully processed and compared with the theoretical profiles calculated by APW for the valence electrons and by tight-binding method for the core electrons, using the impulse approximation. As for the whole profile, the agreement between experiment and theory is fairly good, supporting the validity of the solid-state effect on 4d electrons, at least in niobium, determined by APW method and the applicability of the impulse approximation.

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On single crystal Zn₂Y, the experimental linewidth induced by surface imperfections is compared with the theoretical one. The theoretical calculation is made in consideration of dipole and quadrupole demagnetizations of the imperfections and with the use of the effective exchange constants D_⊥=0.15×10⁻⁹ Oe cm² and D_⁄⁄=9.3×10⁻⁹ Oe cm² within and between the crystallographic c planes. The experimental linewidth agrees well with this calculation rather than the other two results calculated by Sparks-Loudon-Kittel and Seiden-Sparks methods. The ratio of the quadrupole contribution to the dipole increases with decrease of polishing grit size. The extended calculation for the higher order multipoles than the quadrupole achieves the more precise approach of the calculated linewidth to the experimental one.

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An experimental study of the magnetocrystalline anisotropy for Ni–Co alloys has been carried out from 0% to 64% Co concentration and also between 77 and 700 K. The concentration dependence of the magnetocrystalline anisotropy constant K₁ can be described in the form K₁(x)=a+bx+Aexp(−αx), a, b, α and A: constant; x: concentration of cobalt). The temperature where K₁=0 was determined as a function of x and it was found that the diagram of K₁ in the Ni–Co alloy system could be classified into three concentration ranges. The temperature dependence of K₁ has been discussed, based on the result by Carr: K₁(T)=K₁(0)(1−βT⁄T_c)(M_s(T)⁄M_s(0))ⁿ. The value of n and β were estimated as a function of x, and both n and β show an abrupt change around 8%Co where K₁ changes from negative to positive.

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The temperature where the uniaxial anisotropy constant K_u1 vanishes, was measured for hexagonal cobalt alloys containing a small amount (below 2 at%) of 3d or 4d impurities by means of NMR. The temperatures for 1.0 at% alloys were found to be 518±2 (Ti), 542±2 (V), 569±1 (Cr), 525±2 (Mn), 475±1 (Fe), 533±1 (Ni), 520±1 (Cu), 524±3 (Nb), 560±2 (Mo), 519±1 (Ru), 510±2 (Rh), and 506±2 K (Pd). The temperature where K_u1=−2K_u2 was also measured.

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ESR spectra of F-center pairs or clusters in which each electron is either in the ground state or in the relaxed excited state have been observed at 34 GHz and 1.6K in KCl using the optical detection technique. They are analyzed in terms of an appropriate spin-Hamiltonian including the exchange interaction between the electron spins. Also, the change in the intensity of the F-center luminescence due to ESR is calculated by considering an optical pumping cycle in the presence of external static- and microwave- magnetic field. The result is reasonably compared with the experimental results.

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Spontaneous magnetostriction of NiO, which consists of two strain components, is reexamined in detail by Berg-Barrett method. The strain components thus determined are e_x′x′−e_y′y′=−5.4×10⁻⁴ and e_z′x′=0.91×10⁻⁴, respectively. These values are a few times as large as those found previously by Yamada et al. and their signs are in agreement with those expected theoretically. A precise crystal structure with monoclinic symmetry and a corresponding magnetic symmetry has been deduced from the experimental results.

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An X-ray integral breadth analysis has been made for the 111, 200, 220, 311 and 222 diffraction profiles recorded on a Geiger counter X-ray diffractometer from the vacuum-evaporated thin films of silver in the range of thickness 580 to 2125 Å. The analysis based on the methods of single and multiple order of reflection has yielded values for the effective particle sizes and non-uniform micro-strains in the films from a consideration of Gaussian, Cauchy and intermediate parabolic form of distribution, the Gaussian distribution being more favourable. The effective particle size values are found to be small and the strains quite appreciable and these effects which are the manifestations of lattice imperfections present in the films decrease very slowly with increasing film thickness. The dislocation density ρ calculated for the [111] direction from the particle size and strain values for the films above 1000 Å thick is of the order of 10¹¹ cm/cm³ comparable to that observed for the heavily deformed bulk materials. The error analysis done for the first time has further shown the effect of background estimation on the particle size and strain determinations for the range of film thickness considered.

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Anisotropic distribution of the collinear pairs of photons from positron annihilation in a Cu single crystal has been measured around the ⟨100⟩ axis with a conventional long-slit system.
A method for the evaluation of the neck radius of the Fermi surface from the slope of the counting rate of the collinear photon pairs plotted against the azimuth angle around ⟨100⟩ is presented and has been applied to Cu as a test case. The neck radius of Cu thus determined has been found to agree with that given by Halse.
The observed anisotropy is larger than that expected from the topology of the Fermi surface with a Wigner-Seitz evaluation of the higher momentum components. This result suggests the anomalous enhancement of the annihilation rate of the neck electrons.

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The magnetic field dependence of line shapes of the giant quantum attenuation of longitudinal sound waves in bismuth has been investigated in rather weak magnetic fields but in a low Landau quantum number region. It is shown that when the energy interval between an electron Landau level and a hole level located in the neighborhood of the Fermi level decreases, the attenuation peak on the lower field side of the twin peaks is greatly enhanced in height and sharpened in width, but the temperature dependence of the attenuation coefficient of the lower field peak is almost normal. This apparently anomalous angular dependence of the line shape can be well explained by taking account of peculiar field dependence of the deformation potentials which was overlooked in existing theories of the giant quantum attenuation of sound waves in semimetals.

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Warping of the Fermi surface of the electrons in antimony was investigated by using the giant quantum attenuation of sound waves. The magnetic field directions which give rise to two or three extremal cross-sections of the surface were determined and the data were used to construct the Fermi surface shape. The model of the warped surface presented here is partly in agreement with existing models derived from caliper data such as the geometric resonance and R. F. size effect and from area data such as the de Haas-van Alphen effect, but the fine detail is different in several points.

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By use of the single-OPW, the expression for the spin-lattice relaxation time T₁^(Q) due to the quadrupole interaction is derived taking into account the electron interaction. The matrix element of the quadrupole interaction is calculated by use of the representation of the rotation group, and it is found that the effect of the core enhancement is represented by a function, α(q), depending on the magnitude of the scattering wave vector q of an electron and α(2k_F) agrees with the core enhancement factor by Kohn and Vosko. The numerical calculation leads to T₁^(Q)T=32 sec K which is considerably large in comparison with the value, 13 sec K, estimated from the deviation from the Korringa relation due to the electron interaction. When the value of α(2k_F), for silver, estimated by Fukai by use of the single-pseudo-wave function is taken into account, a reasonable value is obtained.

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Interstitial type dislocation loops formed in Al, Au, Cu, Fe and Mo by electron irradiation in a high voltage electron microscope grow proportionally to a smaller power of the irradiation time than unity at lower temperatures under constant irradiation. They grow linearly with the irradiation time at higher temperatures at which vacancies are mobile. The balance of the product of the mobility and concentration between interstitials and vacancies explains the linear growth as well as the observed square root dependence of the growth speed on the irradiation intensity. The temperature dependence of the growth speed can be used to obtain the migration activation energy of vacancies. Temperature independent growth in a very thin specimen is understood as the surface dominant case as sinks. Sink efficiency of an edge dislocation to interstitials and vacancies is discussed.

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ESR Spectra of γ-irradiated KDP and DKDP were measured. From the temperature dependence of the ESR spectra, it was found that the spectra of γ-irradiated DKDP consisted of three types of spectra and these corresponded to three species of radicals. One of the spectra in γ-irradiated KDP showed anomalous temperature dependence of the line width near the Curie temperature. The anomaly of the line width was explained qualitatively by assuming the presence of the fluctuational motion which critically slowed down near the Curie temperature.

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The hole centers produced in CsF crystal irradiated with γ-rays at liguid nitrogen temperature have been studied by electron spin resonance. Three kinds of centers with symmetrical ⟨100⟩ axes were observed and designated as H₁, H₂ and H₃, respectively. The H₁ center has been already assigned to be a self-traped hole. It is found that the H₂ center is composed of two Cs and two F ions and is essentially a F₂⁻ molecular ion on the site of an anion vacancy. When this center is bleached thermally at 150 K, the H₃ center is produced. The analysis of the ESR spectrum of the H₃ center indicates that the center is composed of a Cs ion and an F ion, and that an unpaired electron spends most of the time on an F nucleus and a little on a Cs nucleus.

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The electroabsorption spectra in the indirect transition region are measured on layer compound GaS with experimental condition of incident light normal to the c-axis. Six phonon-assisted transitions are found at 4.2K and eight at 77K. The energy value of the indirect edge was found to be 2591±1 meV at 77 K and 2596±1 meV at 4.2 K. The line shape of the electroabsorption spectra are discussed in connection with the highly anisotropic crystal structure of GaS.

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The temperature dependences of the ultrasound velocities and the thermal expansion have been measured with special care in the vicinity of the phase transition temperatures. All of three elastic stiffness constants of Ca₂Ba(C₂H₅CO₂)₆ single crystal are found as follows: at room temperature C₁₁=7.64±0.05, C₁₂=4.50±0.06 and C₄₄=2.85±0.06 in the unit of 10¹⁰ dyne/cm². The temperature coefficients, dC_ij/dT, of all of the elastic stiffness constants over the range from 110°C to −8.5°C (the upper phase transition temperature) are found to be positive. All the measured modes have shown large jumps at the upper phase transition temperature and clear dips at the lower phase transition temperature.

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The elastic constants of GaSe have been determined by studying Brillouin scattering for various crystal orientations. Depending on the orientation, the spectra exhibit one or two components, which are assigned to specific modes of vibration. From the observed Brillouin frequency shifts, the elastic constants of GaSe are evaluated with a least-square-fit method. The determined values of elastic constants in units of 10¹¹ dyne/cm² are C₁₁=10.5±0.4, C₁₂=−2.9±0.8, C₁₃=−3.32±0.12, C₃₃=3.57±0.08, and C₄₄=1.05±0.4 at room temperature. These values are compared with those obtained by ultrasonic and neutron-scattering methods. It has also been observed that the relative intensities of the Brillouin components are strongly dependent on crystal orientation. An analysis of this variation in intensity gives values of the ratio of the photoelastic constants: |p₁₂⁄p₁₃|≤0.05.

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New interpretation of the phase transition in ammonium Rochelle salt is presented in terms of order-disorder model. Substantial features of the phase transition of the material could be reproduced by a suitable choice of the values of model parameters.

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Correction of dipole fields in a perovskite-type crystal is calculated taking a shear of the crystal into account. It is found that the correction in x- and y- directions under shear stress are the same as those of article concerned to orthorhombic deformation (W. Kinase et al. J. Phys. Chem. Solids 30, (1969) 441). These results are applied to BaTiO₃ crystal, whose tetragonal-orthorhombic phase transition and piezoelectric effect due to shear stress are discussed.

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Frequencies of the faint B_g modes, which have been missing or reported differently by different authors, are predicted by minimizing the least square deviations of all the six external-mode frequencies. For CaWO₄, CaMoO₄, BaWO₄ and BaMoO₄, the reasonable assignment is the combination of the two types of assignments hitherto reported. The B_g frequencies in SrWO₄, NaReO₄, RbReO₄ and AgReO₄, which have not been observed, are predicted. The results show that the faint B_g modes have the highest frequencies of external modes. Dispersion relations and elastic-wave velocities are obtained using the frequencies predicted above. The velocities predicted for CaMoO₄ coincide better with observed values than those corresponding to the frequencies already reported.

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The Glauber approximation has been used to obtain the differential, total, and momentum-transfer cross sections for electron scattering from strongly polar molecules; numerical calculations have been carried out for e+CsCl scattering. The big difference between the Born cross section and the recently published experimental data has been dissolved.

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Induced forward Raman scattering which proceeds in a cascade fashion in a spatially uniform plasma is considered. Two laser lights, the pump and the first Stokes, are assumed to be incident at time t≥0 on the plasma surface. Their frequencies are much higher than ω_p, the electron plasma frequency, but their difference nearly equals ω_p, and initially the pump has much greater amplitude than the first Stokes. Due to a slight, but finite frequency dependence of the coupling constant between two electromagnetic waves, the electron plasma wave is spatially amplified. This amplification saturates at a relatively low level due to local density depression produced by ponderomotive force of the electron plasma wave. Its amplitude shows a spatial oscillation. The growth length, saturation amplitude and amplitude oscillation length of the electron plasma wave are obtained, as well as the effective absorption length of the pump laser light.

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Propagating filament solutions describing an electromagnetic wave trapped by a soliton-like rarefactory ion-wave are obtained, for both homogeneous and weakly inhomogeneous plasmas. The ion wave which traps the electromagnetic field moves at subsonic speed and is assumed to travel normal to the direction of electromagnetic wave propagation. For small ion-wave amplitude, the solution for the homogeneous plasma becomes similar to the electro-acoustic wave discussed by Karpman. When the amplitude of the ion wave is large, nonlinearity and dispersion in ion dynamics become important (in a manner similar to that of K-dV soliton); this causes the propagation speed of the filament to be amplitude dependent. In the weakly inhomogeneous case, a WKB approximation is used and it is found that the filament penetrates deep into overdense regions accompanied by an adiabatic change of its shape and increase of the electromagnetic wave frequency.

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Theoretical test for the accuracy of the M²-expansion solutions to subsonic flow problems has been made by taking the simplest and basic case of the flow past a circular cylinder without circulation. Imai’s equation of two-dimensional compressible flow is used for this purpose and the velocity q is assumed to bear the characteristics of the M²-expansion solutions of this particular flow problem. It is shown then that, under a certain condition, all q’s satisfying the above equation approximately do not differ much as to their magnitudes. This property which is called the ‘appropriateness’ of the equation is utilized to check the accuracy of the M²-expansion solutions, leading to an error estimate in terms of the free stream Mach number M and the adiabatic index γ.

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When a drop of water falls on a horizontal surface of water, a column of rising water is formed. If the water is shallow, and has an inclined bottom, the column is found to bend towards the beach. Photographs are presented and discussed for this case as well as for the cases when the bottom is horizontal and shallow, or deep.

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An analysis is made of unsteady viscous flow generated by starting to move a flat plate impulsively, in a direction normal to its width. The unsteady Stokes equations are reduced to an integral equation with respect to the pressure difference before and behind the plate. The equation is solved by means of a variational method, and the drag coefficient C_D is shown to be given by
(Remark: Graphics omitted.),
where R=Ua⁄ν and t=νt^*⁄a² (t^* being the time from the start of the motion, U the uniform velocity of the plate, a its half width and ν the kinematic viscosity).

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