Excited states in ⁸⁹Y have been investigated by studying elastic and inelastic scattering of 14.71 MeV protons. The scattered protons were detected with a broad range magnetic analyser. The angular distributions of the proton groups corresponding to the ground and thirteen excited states in ⁸⁹Y were obtained. The elastic scattering data are analysed with the optical potential model. All the angular distributions obtained for the inelastic scattering are analysed with the DWBA of one phonon excitation process. The analysis with a single particle excitation process is made for the 0.894 MeV (9/2⁺) and 1.50 MeV (1/2⁺) states and a pretty good fit is obtained for the 0.894 MeV state. The structure of the theoretical curve for the 1.50 MeV state is similar to that of the experimental data. On the basis of these results, the character of the excited states in ⁸⁹Y is discussed.

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The polarization of recoil protons from the reaction γ+p→p+η⁰ was measured for eta center of mass angle of 107.5° at 890 MeV γ-ray energy.
The decay γ-rays from η⁰ were detected by a lead glass Cerenkov counter in coincidence with a recoil proton. Recoil proton polarization was measured by analysing the scattering asymmetry in a carbon plate spark chamber.
According to Minami’s theoretical analysis for the interpretation of the eta-nucleon system, the obtained value of the polarization P=0.54±0.40 is suggesting that the contribution of the interaction in the S_1⁄2 state is predominant over that in the D_3⁄2 state.

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The decay properties of ^178g,mLu were studied by using a high resolution Ge(Li) γ-ray spectrometer, and the half lives of the ground and isomeric states (∼300 keV) were determined to be 30±1 and 23±1 min, respectively. The ground state (1+) decays to the ground state (0+) and to the 1st excited state (2+, 93.1 keV) of ¹⁷⁸Hf with β-rays of 2.05 MeV (60%, log ft=6.6) and of 1.96 MeV (20%, log ft=6.9), respectively. Weak β-branches from ^178gLu to the 1.272 MeV (4%), 1.407 MeV (5%) and 1.440 MeV (10%) levels in ¹⁷⁸Hf were also found. The isomeric state (7−) populates two 8− states at 1.147 MeV (85%, log ft=5.35) and 1.479 MeV (15%, log ft=5.6). The γ-rays observed at 332, 88.8, 426, 326, 213.5 and 93.1 keV correspond to the transitions 8−→8−→8+→6+→4+→2+→0+ in ¹⁷⁸Hf. The configuration of the ground and isomeric states were considered as 1+, (Remark: Graphics omitted.), and 7−, (Remark: Graphics omitted.), respectively.

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In order to investigate the magnetic behavior of praseodymium, measurements were made on the resistivity, the magnetoresistance, and the magnetic susceptibility of the metal and its dilute alloys. The parameters of the crystalline field splitting of the ground state of the Pr³⁺ ion in the d-hcp structure are estimated by analyzing the low temperature susceptibility of the dilute La–Pr alloys on the basis of the point charge model. The parameter of the exchange interaction between conduction electrons and Pr ion is estimated from the high temperature susceptibility data using the Ruderman-Kittel-Kasuya-Yosida theory. The magnetism of praseodymium metal, particularly the nature of the antiferromagnetic state, is discussed in terms of these parameters mentioned above. The conclusion obtained is:
(a) the Pr ion at the cubic site of praseodymium has no magnetic moment at low temperature, and
(b) the sinusoidal arrangement of the magnetic moment occurs only among the ions at the hexagonal site. The resistance minimum phenomenon observed in dilute Pr–Ce alloys seems to support this conclusion.

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The susceptibity of yttrium alloys, containing Tb ions of 0.60 at. % to 3.71 at. %, has been measured in the temperature region from 1.4 °K to room temperature. A systematic deviation of the Néel points from the ξ^2⁄3 dependence where ξ is the effective spin factor, was found. This deviation might be interpreted as due to the existence of a critical concentration of Tb ions for the appearance of a long range magnetic spin ordering. From the Curie constants, we obtain the effective magnetic moment of 10.8 μ_B per Tb ion, which is larger than that for a free Tb³⁺ ion of 9.72 μ_B. The exchange interaction parameter between the conduction electron and the rare earth ion is estimated to be +0.15 eV, which agrees well with the results of the electronic transport phenomenon.

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The band structures of Cr in the paramagnetic- and the perfect antiferromagnetic state are evaluated by the Green’s function method. In the former the crystal potential is set up by the self-consistent procedure proposed by Wakoh, while the alternant orbital theory of Slater is applied to the latter. The spin-dependent part of the potential is determined by the Slater exchange with an adjustable parameter which is determined so as to give an observable value of the magnetic moment. The Fermi surfaces of both the states are calculated. The induced magnetic moment, the electronic specific heat and the magnetic form factor are also evaluated. The agreement between theory and experiment seems to be satisfactory. The stability of the perfect antiferromagnetic state against the paramagnetic state is discussed on the basis of the effective Hamiltonian. Finally, the stability of the spin-density-wave state in Cr is ascribed to the special band structure of Cr.

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Various relaxation times observed in antiferromagnetic resonance of CuCl₂2H₂O are investigated experimentally. Both pulsed and continuous high power microwaves of about 160 milli-watts were applied to the single crystal at low temperatures and the rise and decay times of the induced magnetization M_z, shift of the resonance line, and complex susceptibilities χ′ and χ″ were investigated in detail. Three characteristic relaxation times are specified. The transverse component M_x,y decays with relaxation time T₂ of about 10⁻⁸ sec while the longitudinal component M_z relaxes with T_1a of about 10⁻⁷ sec. An empirical formula for T_1a is obtained as T_1a=(1.1±0.1)×10⁻⁶T^{−(5.0±0.5)} which is considered as the spin-lattice relaxation time. Another relaxation time T_1b of the order of 10⁻³∼10⁻⁵ sec is also observed and the origin of this relaxation is attributed to the lattice-bath heat transfer relaxation.

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KCuF₃ shows a broad peak of the magnetic susceptibility at ∼243°K and has been supposed to be an antiferromagnet. Scatturin et al., on the other hand, have reported that the neutron diffraction shows no magnetic ordering in KCuF₃ even at temperatures as low as 4.2°K. In the discussion, they implies the existence of linear magnetic chains along the c-axis. In order to make sure of their conjecture, the measurements of susceptibility, its anisotropy and specific heat have been made. These measurements assure us that KCuF₃ is a one-dimensional antiferromagnet, with the exchange interaction along the chain being J⁄k=−190°K.

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Perovskite structure fluoride KCuF₃ is a one-dimensional antiferromagnet in which the magnetic coupling is very strong along the c-axis. No detectable magnetic interaction is found along any axis perpendicular to it. The nuclear magnetic resonance shifts of F¹⁹ nuclei both on the a- and c-axes are determined separately from the measurements on the single crystal. From the observed shifts, it is found that the fractions of the unpaired spin on the 2s and 2p orbitals of the F⁻ ions on the c-axis are f_s=0.44% and f_σ=4.93% respectively, whereas the fictitious f_s′ and f_σ′ of the F⁻ ions on the a-axis are 0.16% and 2.34% respectively.

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The quadrupole coupling constants of V⁵¹ and Na²³ have been studied in some vanadates. The results are discussed with respect to structural information, and the quadrupole moment of V⁵¹. On the basis of V⁵¹ coupling constants in vanadates, which are of the order of 3 Mc/s, and other experimental informations, it is concluded that the most appropriate value for Q is −0.04 barn.

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Crystal field theory developed by Abragam and Pryce is used to formulate the anisotropic exchange interactions in FeCl₂·2H₂O. This crystal is antiferromagnetic in which Fe⁺⁺ ions form ferromagnetic linear chains coupling antiferromagnetically to adjacent chains similar to CO⁺⁺ ions in CoCl₂·2H₂O and CoBr₂·2H₂O. There are the similar two abrupt jumps in the high-field magnetization to those in CoCl₂·2H₂O and CoBr₂·2H₂O. The numerical values of exchange integrals are estimated. By the use of these values the above magnetization process can be explained. It is predicted that Schottky anomaly in the specific heat may be detected at about 6.4°K.

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The temperature variations of electronic specific heat are calculated for iron and nickel metals. The density of states curves were determined from the experimental data of low temperature specific heats assuming the rigid band model. The dependences of the exchange energy on magnetization and on temperature are taken into account. Excellent agreements are obtained between the calculated and observed results for iron and nickel metals. It is pointed out that the part of the electronic specific heat due to the temperature variation of the effective field coefficient makes a very important contribution to the specific heat below the Curie temperature.

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Lattice constants and thermomagnetic properties of Cu_1−ξMg_ξFe₂O₄ were studied in detail with changing the quenching temperature and with employing a high oxygen pressure furnace. It was confirmed for CuFe₂O₄ that the previously reported inverse-normal change is not due to the simple thermal effect but due to the change in the degree of oxidation, or, due to the generation of Cu¹⁺. This is not the case for MgFe₂O₄ and it was shown experimentally and theoretically that the reasonable representation of the activation energy Θ as a function of x, (Mg_xFe_1−x) [Mg_1−xFe_1+x]O₄, is not Θ=Θ₀−Θ₁x but Θ=Θ₀+Θ₁x−Θ₂x².

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In the first part of the experiment, the deposition rate, r(Å/min), was changed systematically from about 10 Å/min to 10⁴ Å/min. The epitaxial temperture was found about 150°C higher under the highest deposition rate than the lowest rate. The result was in accordance with the theory proposed by Walton. In the second part of the experiment, in which air- and vacuum-cleaved surfaces were used as substrates, the residual gas in the evaporation chamber was specified to N₂, O₂ and H₂O of about 10⁻⁵ Torr. It was concluded that the epitaxial temperature was influenced only by partial pressure of water vapour, P_H2O. By the combination of the above two results and the results obtained by Ino et al. in ultra high vacua, it is infered on empirical base that the epitaxial temperature depends upon the ratio P_H2O/r.

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The ferroelectrics whose spontaneous polarization vector cannot be turned in the opposite direction but can be turned in another direction by means of an electric field are considered to be possible, although none of them have yet been discovered. As the first stage of the study of these ferroelectrics, it is shown that there are, in all, 33 possible species of them as distinguished according to the point group of the prototype and the total number and orientation of the equivalent ferroelectric axes.

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An instability of a magnetoplasma surface wave is investigated. The magnetoplasma surface wave is an electrostatic wave having a frequency independent of wave number. The wave propagates along the interface between a single-component solid state plasma and an insulator, in the presence of an external magnetic field. When two semiconductor wafers are separated by a thin insulator, the wave propagating along one interface interacts with the other wave propagating along the other interface. It is found that a two stream type instability, or a resistive wall type instability is induced by the drifting of surface charge.

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A theory is proposed to explain the observed fact that the high density phonon flux in piezoelectric substances damps non-exponentially. The calculation shows that the fourth-order piezoelectric phonon-electron interaction causes damping, even if the drift velocity of electrons exceeds the velocity of sound and, hence, the phonon flux is amplified due to the lowest order interaction.

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The double injection phenomena in n-InSb were studied theoretically and experimentally over a wide range of current density at 77°K. As the electric field E increases, electrons and holes are injected into the bulk and the current density j is approximately proportional to E^3⁄2 for high injection levels at fields up to a few tens of volt/cm. As the field increases further the j–E curve becomes flat. In the high current region, a current-controlled negative resistances is observed.
The theory for the double injection was extended to include hot electron effects. In n-InSb, the ambipolar density velocity can change its sign from that of the low field density velocity, if the field is high enough to heat up the electrons, and the injected hole density is sufficiently high. The flattening in the j–E curve was explained theoretically taking into account the sign change in the density velocity. The sign change in combination with the blocking of the hole current flow at the cathode also accounts for the negative resistance.

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Electron spin resonance experiments on Ag-doped CdS have been done at 1.5°K and at X-band. A resonance line characterized by the g-values, g_⁄⁄=1.226 and g_⊥=1.509, is observed under irradiation of light in characteristic bands. As a possible model of the magnetic center, which is designated by the A center and is responsible for this resonance line, we present Ag²⁺ occupying a Cd site in the crystal. From this model the behaviors of the center under illumination are discussed. An association of Ag⁺ and a sulfur vacancy explains reasonably well the differences in the conditions of the appearance of A centers and electron trappipg centers among four kinds of CdS crystals which differ from each other only in the manner of incorporating the Ag impurities and in the crystal growth conditions. The relation between ESR measurements and luminescence ones is discussed.

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The energies of the ground states of the interstitial lithium donor in silicon have been calculated for interstitial T_d and D_3d site symmetries. It is shown that the assumption of the D_3d site symmetry for the lithium donor is favorable for the experimental fact of an “inverted” Group-V-like ground state. The lowest ground state is the 1s(A_2u+E_g+E_u) state with the ionization energy of 30 MeV, lying about 1.5 MeV below the 1s(A_1g) state. The corresponding observed values are 32.81 MeV and 1.8 MeV, respectively. It is shown that the “inverted” Group-V-like ground state is attributed to the orthogonalization effect to the core state of lithium in silicon and the interstitial nature of the lithium donor.

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Photoluminescence and electrophotoluminescence of NaCl : Ag are studied by excitation of the phosphor with u.v. light of the fundamental absorption region. Enhancement of luminescence is observed, when an electric field is applied to the phosphor. The field effect appears only when the polarity of the field is made negative on the illuminated side. As to the dependence on photon energy the enhancement of luminescence sets on near the step which is believed to correspond to the threshold of the band-to-band transition. Intrinsic electroluminescence is also observed by warming NaCl : Ag crystal above 100°C. As a mechanism for the electric field effect on luminescence intensity the acceleration-collision excitation model is proposed, which makes it possible to explain most of the experimental facts.

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Measurements of dielectric constant ε′ and dielectric loss ε″ of Ca₂Sr(C₂H₅CO₂)₆ along the ferroelectric axis have been made between 100 kHz and 3.3 kMHz as functions of temperature. Dielectric dispersion arising from the dipolar reorientation takes place mainly in the frequency range from about 10⁷ Hz to 10⁸ Hz, where ε′(T) shows double peaks with minimums at the Curie point. ε″(T) becomes maximum at the Curie point, and the maximum value decreases with the increase of the frequency. The results obtained can be explained by the critical slowing-down of the polarization relaxation process.

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Electron spin resonance spectra of the (nd)¹ ions in the rutile-type crystals are explained in terms of the crystalline field theory. It is shown that the mixing of the d(z²) orbital into the d(x²−y²) orbital by the rhombic component of the crystal field with D_2h symmetry plays an essential role. The amount of this mixing together with values of ⟨1⁄r³⟩ and of the core polarization parameter χ are determined by analysing the ESR spectra. The energy levels of the excited d-orbitals are also estimated. Finally, the NMR shift of V⁵¹ in VO₂ observed by Umeda et al. is shown to be explained well by using the electronic structure of the V⁴⁺ ion in VO₂ determined from the analysis of the ESR spectra.

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Young’s modulus and modulus of rigidity of cold-drawn and subsequently annealed electrolytic copper- and brass-rods were measured and compared. The results showed that: (1) In cold-drawn state, Young’s modulus E, for instance, has a Variation-Latitude of ΔE>4000 kp/mm², (2) during recrystallization ΔE decreases to a minimum of ΔE_r=ΔE_min∼1600 kp/mm², (3) this variation of ΔE is first of all the result of the change of a texture-factor Q=⟨111⟩⁄⟨100⟩, (4) the Variation-Latitude of modulus of rigidity for all different states of materials is ΔG<800 kp/mm² and shows above all microscopic and submicroscopic structural defects.

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Some new results obtained by studying cadmium chloride and mercuric chloride as poisons in ethyl alcohol containing different percentages of water are presented. The role of water in changing the etch pit morphology on the cleavage faces of sodium chloride crystals is discussed. How the results of the earlier workers could be obtained with different percentages of alcohol is described.

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The origin of Kα satellites was generally believed to be one electron transition (1s→2p) between doubly ionized states 1s2s→2s2p and 1s2p→2p2p. It was assumed that these ionizations take place due to, rather than formerly supposed direct collisions, the electron shake-off processes by a sudden change of the effective nuclear charge just after the ejection of K electron from the atom, which is subject to an impinging electron or X-ray photon. The ratio of the probabilities for occurrence of a 1s2p state to 1s2s state is calculated for neon by sudden approximation. On the other hand, by using the theory for the line strengths of multiplets and experimental data of X-ray spectra, this ratio is also computed. These two values coincide with each other, if a reasonable small value (almost zero) is chosen for the Coster-Kronig yield.

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A simple but general approach to obtain the stability criteria is presented through an elementary proof of the uniqueness theorem for the higher order parabolic equations by constructing an energy inequality. The theorem is applied to the isothermal, resistive, viscous and incompressible magnetohy-drodynamical (MHD) equations of a sheet pinch where we reduce the equations into an equation governing the two dimensional vorticity and an equation governing the parallel motion with respect to the acting force. The theorem yields the conditions for the stable parallel motion and for the conservation of vorticity. The result is compared with other works and the effects of viscosity and resistivity are discussed.

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The dynamic behavior of a helium plasma produced in a magnetic mirror field by a coil with large length and diameter was investigated with high speed cameras and by spectroscopic observations. The produced plasma is unstable at the initial pressure above 50 mTorr, but is rather stable and drift-free at pressures below 25 mTorr. The plasma contracts axially to the midplane. The velocity of contraction is faster at higher pressures. After the maximum contraction the plasma expands to the mirror plane with a velocity of about 2×10⁶ cm/sec nearly independent of the initial pressure. During the expansion, the plasma decreases at the midplane and increases at the mirror plane. In the case of the drift-free plasma, the e-folding times of decreasing plasma at the midplane are 10∼20 μ sec increasing with decreasing initial pressure. These results show that the end loss of dense plasma from the mirror field is affected by a non-steady axial plasma motion which seems to originate in the axially inhomogeneous distribution of the produced plasma.

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Volume changes of Mixing of binary liquid mixtures, Dioxan+Fluorobenzene, Dioxan+Chlorobenzene, Dioxan+Bromobenzene, Benzene+Bromobezence and Cyclohexane+Bromobenzene have been measured. The results have been analyzed on the basis of the theory due to Balescu.

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