Rapidity correlations among hadrons produced at 200 GeV/c proton-nucleus interactions in emulsion are investigated. A two step mechanism is considered in which cluster of hadrons are produced independently. The analysis of the data shows an evidence for short-range correlations. The average number of particles (pions) emerging out of a cluster is found to be at least three at this energy.

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Inelastic virtual Compton scattering of photons from nucleons for lepton-pair production, γ+p(n)→γ^*+anything and γ^*→l⁺+l⁻, is proposed to study not only the quark structure of the nucleon but that of the photon. In a special kinematical region, the cross section for this process measures the sum of quartic charges of quarks in the nucleon while in another region, it does the quark distribution function of the photon. The magnitude of the relevant cross section is estimated to be of order 10⁻³⁴ cm², which seems to be feasible for any future experiments by photon beams at energies higher than 1 GeV.

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The examination of published differential and double differential cross section data for the reaction ²⁴Mg(d, pγ)²⁵Mg at 10 MeV shows that the angular distributions can not be reproduced completely by DWBA calculations, particularly at backward angles. This discrepancy may be due to the presence of compound nucleus (CN) contributions. The CN contributions calculated from Hauser-Feshbach theory have been added to the double differential cross sections calculated from DWBA. It has been shown that the fits to the double differential cross sections are markedly improved, like the differential cross sections, by the addition of CN contributions. Moreover the differential cross section of the levels with spin 7/2⁺ and 9/2⁺ and double differential cross sections for 3→0 and 8→3 correlations, which do not show the stripping pattern are close to those predicted by HF calculations. Thus it is possible to account for the strength of the levels, which do not have the obvious direct stripping pattern, simply by CN processes.

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The nuclear structure of ⁸⁹Zr was studied using the ⁸⁷Sr(α, 2nγ)⁸⁹Zr and ⁸⁶Sr(α, nγ)⁸⁹Zr reactions. Gamma-gamma coincidence and angular distributions of γ-rays were measured. New levels with spin values up to 23/2⁺ were proposed at 2454.0, 3109.3 and 3575.7 keV. The result of the present experiment is discussed on the basis of the shell model.

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Magnetic field dependence of the neutron Bragg scattering as well as the diffuse scattering intensities in K₂CuF₄ has been observed as a function of temperature. It is found that about 42% of the observed Bragg scattering intensity is due to a giant fluctuation of spins which can be erased by very weak internal field. This fluctuation part is thought to be a new phase with condensation of magnons. The rest 58% corresponds to the phase with conventional long range order. The critical points for these two phases are the same within the experimental errors.

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We show that the breakdown of analyticity is not found in average Green’s functions which are obtained on the basis of the cluster coherent potential approximation for systems with substitutional disorder if the one particle total hamiltonian for a given configuration is expressed as a sum of homomorphic single-cluster hamiltonians. Disorder can be site-diagonal and/or off-diagonal. In this article the emphasis is laid on off-diagonal cases. We first treat three-dimensional disordered systems with a semielliptic distribution of nearest neighbour transfers {V_ij}. We also apply our homomorphic cluster coherent approximation (HCPA) to the bond percolation problem; we obtain the densities of states which show characteristic features found through a computer simulation.

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We apply the homomorphic cluster coherent potential approximation (HCPA) to systems with site-diagonal and/or off-diagonal randomness. We show numerically that the average Green’s function obtained on the basis of the HCPA is analytic off the real axis on the complex energy plane. We also show that the HCPA reproduces the ordinary single-site CPA and the molecular CPA when systems include only diagonal disorder. The HCPA is advantageous in that it can deal with both site-diagonal and off-diagonal disorder in a unified manner. We also present a numerical result for a disordered chain by taking both kinds of disorder into account. The density of states calculated in the HCPA is in good agreement with the result of a computer simulation.

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Charge density wave (CDW) states of a two-dimensional electron system occupying only the lowest Landau subband are investigated at T=0 by the Hartree-Fock approximation. It is shown that even in the high density region the CDW state has the same periodicity as that of a Wigner lattice but has considerable overlaps of wave functions of nearby electrons. Hence the Wigner lattice at low density changes smoothly to the CDW state at higher density. This coincidence of the periodicity of the CDW with that of the Wigner lattice results from the appearance of a large gap at the Fermi level in the energy spectrum.

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The prototypic phase of WO₃ is considered to be the tetragonal phase with the space group D_4h⁷, that is the highest temperature phase, to explain systematically the displasive successive phase transitions of WO₃.
The normal modes at the points Γ, Z, M and A in the tetragonal Brillouin zone are studied with the help of the group theory and are compared with the normal modes in the cubic WO₃ that is the hypothetic prototype with the space group O_h¹.
The condensed modes in each phase of WO₃ are described by the irreducible representations of the normal modes in the tetragonal WO₃, referring to the results of X-ray and neutron diffraction studies.

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Competitive behavior of two channels of resonant Raman scattering and luminescence is discussed for the giant two-photon excitation of excitonic molecules in CuCl. The stochastic theory of intermediate state interaction is applied to describe the time-integrated and time-resolved emission spectra of the excitonic molecule excited resonantly by a short light pulse. Particularly as for the time-resolved spectrum, the frequency-time uncertainty due to the finite observation time is incorporated in the present theory. Our theory explains the observed characteristics of the emission spectra, and the relaxation constants of the excitonic molecule and the exciton in the final state are determined from comparison between the observed and calculated spectra.

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The sound attenuation in bismuth at low temperature has been measured under the conditions: the longitudinal sound wave vector q is applied along the trigonal axis and the field H is parallel to a trigonal-bisectrix plane. For q∧H=88.0°±0.3° and 92.2°±0.3°, a quite large attenuation peak has been found, which is due to the second and third lowest Landau levels of the electrons in the degenerated non-principal electron pockets. Its attenuation coefficient α(T, H_p) shows fairly strong temperature dependence and frequency dependence as compared with those in other orientations. A theoretical analysis is presented to explain a part of the anomalies.

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The tilt effect in sound attenuation at low temperatures has been studied for bismuth to derive the relaxation time of the limiting point carriers. The comparison between the experimental data and a theory leads to a result that for most cases of orientations of the magnetic field and the sound wave vector the relaxation time is of the order of 1∼6×10⁻⁹ sec: the value is one order of magnitude longer than those from other classical transport phenomena. On the contrary to bismuth, the tilt effect is absent even in a very dilute alloy Bi_0.999Sb_0.001. This absence of the tilt effect is tentatively explained by assuming random diffractions of the sound wave propagation direction due to a spatial inhomogeneity of antimony concentration in the alloy.

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The magnetic susceptibility and the heat capacity of a layered manganese compound Mn(NH₃)₂Ni(CN)₄2C₁₂H₁₀ have been measured down to the temperature, T=0.5 T_N. A symmetric logarithmic singularity of heat capacity, which was found for isomorphic nickel compound Ni(NH₃)₂Ni(CN)₄2C₁₂H₁₀ at T_N=0.800±0.005 K has been observed, in this case, at T_N=0.172±0.001 K. The singularity of magnetic susceptibility at T_N is consistent with that of heat capacity.

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Magnetization measurements were made on the mixed anion system CuCr₂Se_4−xY_x (Y=Cl, Br), in order to investigate the concentration dependence of the Curie constant and the exchange stiffness constant D as obtained from the magnetization measurements at low temperatures. From the former experiment, it is shown that the electronic state is closer to the Lotgering model rather than the Goodenough one, which is consistent with the result of our polarized neutron experiment. However, even the Lotgering model does not give satisfactory agreement with experiment unless we take account of the metallic character of the substances. Furthermore, from the latter one, it is shown that the hole-carrier responsible for the metallic conduction contributes mainly to the ferromagnetic coupling between the magnetic moments on the second-neighbour Cr atoms. The mechanism of the ferromagnetism is discussed on the basis of the above electronic state.

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Mössbauer spectra of the low temperature phase of single crystal magnetite were measured with a magnetic field along various directions in (1\bar10) plane after cooled in the magnetic field along [112]. Measured spectra were found to be sensitive to the direction of the applied magnetic field. As the result of detailed analysis two kinds of Fe²⁺ ions (Fe²⁺–I and II) were clearly recognized and the principal Z-axis of EFG was found to be along [100] or [010] for Fe²⁺–I and [001] for Fe²⁺–II. Since the observed anisotropy of the internal magnetic field is well described by EFG observed, angular momentum of each Fe²⁺ ion is suggested to be quenched.

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The effects of the anisotropic exchange interactions on the magnetic ordered states, the magnetization and the magnetic susceptibility of the singlet ground state system of spin one and with a uniaxial anisotropic D-term are investigated by the molecular field theory in the vicinity of the level crossing field H\simeqD⁄gμ_B. It is shown that the induced ordered state without the transverse component of magnetization appears in a certain range of magnetic field as the spin dimensionality decreases. It has also turned out that the phase transition between this ordered state and the canted antiferromagnetic state ordinarily found for the isotropic singlet ground state system is of the first order.

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The EPR linewidth and the line shape of impurity-doped two-dimensional antiferromagnets K₂Mn_cMg_1−cF₄ (c\gtrsim0.35) in X-band region were investigated at room temperature. The minimum of the linewidth at a “magic angle” θ=55° (θ is the angle of dc field with respect to the c axis of the crystal) was observed indicating the dominancy of q\simeq0 diffusive mode in the dipolar interaction. The line shape at θ=0° approaches to Gaussian from nearly Lorentzian decreasing Mn contents. This fact can be explained by the formation of the broken chains of Mn atoms in the crystal. The calculated line shape for Mn chain consisting of 30 atoms agrees with the experimental results for c=0.35.
The low-temperature line-broadening of the impure two-dimensional systems was suppressed and the minimum of the width at the “magic angle” did not disappear even at the lowest temperatures on the contrary to the pure systems.

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We report low-temperature specific heat measurements on four samples with chemical formulas Mn_xNi_1−xCl₂·nH₂O (n=4 or 6). Their compositions range from x=0.88 to x=0.16. They all show fairly well-defined antiferromagnetic-paramagnetic transitions in the liquid helium 4 region (1.68 K to 4.51 K). A simple random mean field theory fails to account for the variation of critical temperature with composition.

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Magnetic measurements were made, in the weak ferromagnetic temperature region (≤30 K) and in fields to 55 kOe, on two single crystal samples without and with Co impurities, respectively. The magnetization along α direction is well expressed by M(α)=M₀(α)+χ_w(α)H at higher fields to 55 kOe without any anomaly like a spin flip. The ratio of M₀[001] : M₀[110] : M₀[111] is equal to almost 1 : 1⁄\sqrt2 : 1⁄\sqrt3. χ_w(α) was found to be almost temperature independent, and to be weakly anisotropic. The transition at T_c is of the first order and T_c increased in magnetic fields (dT_c⁄dH=+(2.7±0.5)×10⁻³ K/kOe). The entropy change was estimated as 0.7±0.2 (J/K·mol). Co impurities were found to strongly affect some of magnetic properties. Discussions are given on origins of weak ferromagnetism together with other properties. The origin proposed by Yoshimori et al. seems to work in NiS₂.

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The temperature dependence of the easy axis magnetization in the ferromagnetic phase of MnP is measured to an accuracy of ΔM⁄M<±5×10⁻⁴ over a range from 4.2 K to 280 K. Instead of the usual T^3⁄2 law, T ln T dependence holds up to about T_c⁄2. The following spin wave dispersion is expected to exsist at 0 K; along the a axis it is nearly constant up to q_a=Q and increases very rapidly beyond Q, where Q is the screw propagation vector, while for perpendicular to the a axis it is quadratic in q_⊥. At a finite temperature, the calculated two-magnon renormalization causes increase of the magnon energy near q_a∼Q which induces an anomalous suppression for decrease of magnetization in MnP. The ferro-screw phase transition seems also to be due to this effect.

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A theoretical analysis of the magnetic specific heat of Fe(HCOO)₂·2H₂O is performed on the basis of a two site model, R_A=1⁄2 and S_B=2, where R_A is the fictitious spin for the lowest doublet. The contribution to the specific heat from A and B sites can be calculated separately and the effect of weak AB interaction is considered by the high-temperature series expansion technique. The experimental result turns out to be well explained by introducing a large S_z⁴-term for B site ions. As a microscopic origin of S_z⁴-term, the magnetostrictive energy at B site is shown to be favorable.

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Explicit expressions for the effective interaction Hamiltonian in the case of degenerate orbitals and the spin dependent transition moment for two exciton excitation which had not been derived in the previous paper (J. Phys. Soc. Japan 45 (1978) 1559) are given. The formalism can easily be extended to include the effect of the spin-orbit interaction in the effective Hamiltonian.

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Study of superhyperfine interaction in {Cu(NH₃)₄}²⁺ ion complex was done by using the ESR-data-accumulation system. The main purposes of this study are to ascertain the existence of magnetic electrons on nitrogen atoms and to find a reasonable explanation of two-dimensional magnetic properties of CTS (copper tetra-amine sulfate, Cu(NH₃)₄SO₄H₂O). The experiment was done by doping {Cu(NH₃)₄}²⁺ in Pd(NH₃)₄Cl₂H₂O and the results show that about 14% of the unpaired electron spin are found on nitrogen atoms.

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The magnetic properties of the metallic compound CoS₂ have been studied microscopically using the cw and pulsed NMR techniques in both the paramagnetic and the ferromagnetic states. The ⁵⁹Co Knight shift is shown to be in linear relation with the uniform susceptibility with a hyperfine coupling constant of −148.6 kOe/spin. The d-spin susceptibility χ_d derived from the Knight shift measurements is found to obey the Curie-Weiss law above 420 K with the effective moment corresponding to one electron per Co atom, while the slope in the 1/χ_d vs T plot below 420 K is smaller than that above 420 K. The temperature and external field dependences of the NMR frequency in the ferromagnetic state have also been measured in detail. The results of our measurements are in accord with the predictions based on the general theory of spin fluctuations and yield a conclusion that CoS₂ can be classified as a nearly saturated narrow band ferromagnet.

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An EPR investigation of Gd³⁺ in RbCdF₃ has been made over a temperature range 296–77 K. The spectra of two type centers with cubic and ⟨100⟩ tetragonal symmetry have been observed at 296 K. The temperature dependence of the tetragonal spectrum in the [100] field direction evidently shows the presence of the phase transition at about 124 K. The field-direction dependence of the tetragonal center in the (001) plane at 77 K indicates conclusively that the Gd³⁺ ion substitutes for a Cd²⁺ site and the charge compensator along the [100] direction should be its nearest neighbor Cd²⁺ vacancy. The results of the temperature and field-direction dependence are discussed qualitatively by the change of the crystal field caused by the phase transition.

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Specific heat in ferromagnetic phase, screw phase and fan phase of MnP have been measured from 1.5 K to 8.0 K. In the ferromagnetic phase, electronic and phonon specific heat are separated from the magnon specific heat estimated from the previous experiment. The following values are obtained. γ^ferro=9.65±0.5 mj/mole·deg² and θ_D=570₋₇₀⁺²¹⁰ K. The large value of γ^ferro suggests that the d-electrons exist at the Fermi level and form bands. In the screw and the fan phases, the γ values are evaluated to be, γ^screw=5.4∼7.6 mj/mole·deg² and γ^fan=6.9∼9.1 mj/mole·deg², decreasing by 20∼30% from γ^ferro. This is consistent with the nesting model proposed before.

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Several kinds of elastic anomalies occur as the preceding phenomena of the martensitic phase transition in Au–Ag–Cd alloys. Besides the softening of C′=(C₁₁−C₁₂)⁄2, both C′ and C₄₄ exhibit cooperative and non-linear changes near the transition point. Due to such changes, another type of the softening is induced in the special mode, which is responsible to the formation of close packed planes in the martensite. Based on the obtained results, nature of the special mode softening and the transition mechanism in the β phase alloys are briefly considered.

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The phase transition in Pb_1−xGe_xTe with x=0.03∼0.1 was studied by Raman scattering and ultrasonic velocity measurements. Below T_c the frequency of the A₁-mode is 1.99×10²³(T_c−T) rad²/sec² and the E-mode 5.32×10²³(T_c−T) rad²/sec² for x=0.05. The ultrasonic velocity shows a step-like behaviors at T_c. Just above T_c the normal elastic moduli are C₁₁=11.0×10¹¹, C₁₂=0.02×10¹¹ and C₄₄=1.35×10¹¹ in dyn/cm². The steps are ΔC₁₁=1.52×10¹¹, ΔC₁₂=−0.20×10¹¹ and ΔC₄₄=0.26×10¹¹ in dyn/cm². The parameters of the free energy expansion were calculated by using the above results together with the data of the shear strain. The order parameter, the spontaneous strain and the TO-phonon frequency above T_c which were estimated from thus obtained parameters are consistent with the results experimentally obtained satisfactorily.

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A pseudopotential of As crystal is determined self-consistently from the Topp-Hopfield type model potential of As atom by using the Xα approximation based on the Kohn-Sham formalism. The resulting band structures in the neighborhood of the points T and L are similar to those given by Lin and Falicov. The lowest crystal energy is obtained at the observed structural parameter of the unusual A7 structure for a many special points sampling. The equilibrium lattice constant and the compressibility are calculated. Some discrepancies between the calculated and experimental values are discussed.

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With the use of magnetic field modulation technique up to eighteen magnetophonon peaks are observed in the transverse and longitudinal magnetoresistance of high purity epitaxial n-GaAs. Fourier analysis reveals the second harmonic component resulting in a sharpening of the oscillatory structure in the transverse magnetoresistance and extrema associated with the two LO phonon process in the longitudinal magnetoresistance in addition to the ordinary magnetophonon series. Two methods are described to obtain the damping factor \barγ which is found to be 0.63 from the Fourier analysis and 0.60 from the method described in this paper for the specimen with the highest mobility (1.7×10⁵ cm²/V·s) at 77 K. The temperature dependence of \barγ for the high purity n-GaAs exhibits a variation T^0.25 at low temperatures, which indicates an importance of the band tailing effect for the damping process. The effective mass is determined to be m^*=0.0682m₀ at 77 K.

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The temperature dependence of the anomalous ultrasonic attenuation in Ca₂Sr(C₂H₅CO₂)₆ has been measured in the frequency range 10.3–72.1 MHz above and below the ferroelectric phase transition temperature. Shift of the attenuation peaks towards the lower temperature side with increasing frequency has been observed. It has turned out that the behavior of the anomalies of the ultrasonic attenuation in the vicinity of ferroelectric phase transition point can be well explained by the Levanyuk theory. The elastic relaxation time τ=3.0×10⁻⁹⁄(T_I−T) sec. estimated from the first order (piezoelectric) effect in the sound attenuation is found to be quite close to the dielectric relaxation time at T_I−T=1°C.

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Using E_0⁄0 cavity resonator with axial capillary, measurements at 3 GHz of dielectric constant and loss factor of liquid ammonia have been made over the temperature range −40 to +20°C. There is consistancy in relaxation time variation from 1.6×10⁻¹³ sec at −30°C to 0.9×10⁻¹³ sec at +15°C, the spread parameter α is in the region 0.5–0.7. The activation energy for relaxation was found to be 4±2 kcal/mole, indicating the breakage of several NHN bonds in the relaxation process.

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On the basis of Onsager’s phenomenological equation of motion, the generalized form of susceptibility is derived. This includes the damped harmonic oscillator (DHO), Van Vleck-Weisskopf and Fröhlich susceptibility (VWF) and Debye relaxational model as different limiting cases, and is equivalent to that obtained from the Bloch equation for the Ising model in a transverse field which are used in the pseudo-spin model for KDP-type crystals. Characteristics and mutual relations of susceptibilities are discussed with an emphasis on the difference between DHO and VWF. For a heavily damped mode, DHO becomes difficult to physically interpret since the eigenfrequency and the damping factor may lose their original meaning. In such cases, the only important parameter is the distance from the origin to the pole of χ(ω) in the complex ω-plane.

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The Raman spectra of an overdamped B₂-mode in KH_2(1−x)D_2xPO₄ crystals have been analyzed with the generalized form of single-mode susceptibility. It has been shown that the absolute value of a pole \ ildeω₁ of χ(ω) which makes a larger contribution to the line shape, e.g., in case of a damped harmonic oscillator, a pole closest to the origin, is the most appropriate parameter to describe the phase transition regardless of the model adopted in the analysis. The |ω₁| was proved to have a linear temperature dependence for any x in the neighborhood of T_c. It is suggested that there exists a critical degree of deuteration x_c≅0.2, at which the mechanism of the phase transition changes qualitatively.

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The anisotropy of the transverse magnetoresistance and the magnetic field dependence have been studied in single crystals of gadolinium in fields up to 100 kOe at a temperature of 4.2 K. These results suggest the presence of open orbits along the [0001] direction for all field directions in the (0001) plane and along the [10\bar10] direction for the field direction about 20° from the [0001] axis in the (10\bar10) plane. The results also can qualitatively be interpreted from the Fermi surface model determined by Batallan and Sommers.

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Three kinds of photosensitive ESR signals (V₁, V₂, F) have been found to be produced by electron irradiation. Signals V₁ and V₂ (V₁ having g_⁄⁄=2.0030, g_⊥=2.0550, and axial symmetry along the twinning [111]_w axis; V₂ having g_⁄⁄=2.0030, g_⊥=2.0530, and axial symmetry along another ⟨111⟩ axis) are ascribed to Zn vacancies (V centers) situated at stacking faults; V₁ is due to a hole localized on the S ion next to the Zn vacancy along the [111]_w axis; V₂ is due to a hole localized on one of the other three S ions next to the Zn vacancy. The signal F (g=2.0027 and isotropic) is ascribed to F centers. The excitation, quenching, and enhancing bands of the V centers are around 2.85 eV, 1.8 eV, and 1.3 eV, respectively. For F centers the excitation bands are around 3.4 eV and 1.8 eV, while the quenching bands are around 2.8 eV and 2.1 eV. A band model is proposed to interpret these photosensitivities.

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The vibronic scheme of the relaxed excited state (RES) of the F center which includes the 2Γ₁⁺, Γ₃⁺, and Γ₄⁻-mode interactions has been developed. Formulae of the morphic effects have been derived. The vibronic parameter values for NaF, KF, KCl, KBr, RbF, RbCl, and RbBr are determined from the consistent analysis of the temperature dependence of the radiative lifetime and of the Stark polarization. Available data of the temperature dependence of the stress-induced polarization are consistently explained. Using parameter values, the dipole moment and stress coupling coefficient (Γ₃⁺-mode) are determined; the red Stark shift is interpreted. By including the spin-orbit interaction, the forms of the magnetic effects are derived. The spin-orbit interaction constant, the orbital g-factor, and the spin polarization in the RES are determined from the analysis of experimental data.

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A study is made of the resonance Raman scattering in a linearly-coupled localized-electron phonon system with doubly degenerate excited level. For an arbitrary coupling strength, the degree of polarization and the secondary radiation intensity are calculated as a function of the incident and scattered photon energies. The polarization relaxation mechanism, as well as the energy relaxation mechanism, during the resonant second-order optical process is clarified. It is found that in the closely resonant case, not only the Raman lines but also the luminescence lines are highly polarized. This phenomenon reflects the distinctive feature inherent in the linear interaction system.

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The chemical shifts of the X-ray K absorption discontinuities of copper and cobalt and of the L_III absorption discontinuity of samarium have been studied in the compounds SmCu₅ and SmCo₅, using a 40 cm Cauchois type bent crystal X-ray spectrograph. The extended fine structure (EFS) observed in the vicinity of the K absorption discontinuities of copper and cobalt in the pure metals and in the two compounds has also been studied. The results on the chemical shifts and the EFS have been briefly analysed in terms of the chemical bonding.

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Difference in the yields of electron emission from (111) and (\bar1\bar1\bar1) planes of a polar crystal of gallium phosphide is studied under the diffraction condition of X-rays. The symmetric 111 and \bar1\bar1\bar1 Bragg-case diffractions are used in the double-crystal arrangement of (+, −) setting for Cu Kα radiation. Profiles of the yield curve of Ga L-photoelectrons obtained for two polar planes differ markedly from each other because of the difference in the X-ray wave fields formed in the crystal.

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The K Auger electron spectra have been measured for boron and fluorine bombarded with C²⁺, N²⁺ and O²⁺ ions at 0.75–2.50 MeV impact energies. Those for N²⁺ and O²⁺ in the cases of the F+N²⁺ and F+O²⁺ impacts have also been measured. The derived cross sections for K shell excitation have agreed well with the MO model theories of Taulbjerg et al. and Meyerhof. The results support that the 2p vacancies of both colliding partners mixingly contribute to the cross section.
The K shell ionization cross sections have been derived for both target atoms excited by protons and alpha particles, the results of which being generally consistent with the theories of plane wave Born approximation and binary encounter approximation.

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Variation of a naturally excited electron wave or waves by an externally launched wave is studied in electron beam-plasma systems, where the wave saturates due to a temperature broadening of beam. In a counter stream type, when the external wave suppresses the amplitude of a natural wave, the beam energy distribution function shows no appreciable change, and both waves compete with each other within a range that the total wave energy is not altered much. Equations describing this mode coupling for multimodes are similar to a gas laser system. In the case of single stream type, the energy distribution function is altered more by suppression. An approach is made to explain the suppression phenomenon of travelling waves.

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Shear Alfven wave heating experiments are reported in which a bulk electron heating of the toroidal plasma for a high initial temperature plasma (T_e>50 eV) and a local electron heating for a lower temperature plasma were observed. The results indicate the excitation of the kinetic shear Alfven wave and are consistent with the theoretical calculation of the damping length of the wave.

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The stability of a two-layer film flow of viscous fluids down an inclined plane is studied by the use of the derivative expansion method. Multiple scales are introduced, and two nonlinear asymptotic equations are derived for the elevation of the free and internal surfaces. The stability of the two-layer flow is governed by four nondimensional parameters of ratios of density, kinematic viscosity, surface tension and layer thickness. For specific case of water and benzene layers, it is shown that, when the heavier fluid (water) is in the lower layer, the two-layer flow is similar to a single fluid flow. On the other hand, when the heavier fluid is in the upper, layer reversion is expected to occur under a certain condition of the film thickness ratio.

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For a steady plane parallel flow of an inviscid, incompressible, infinitely conducting fluid of variable density under gravity and uniform magnetic field acting along the direction of flow, it is shown that the complex wave velocity, for an unstable mode lies in a region of semi-ellipse type.

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Analysis is made of inhomogeneous turbulent diffusion of a passive scalar in the presence of mean scalar and velocity fields. A general expression is found for the scalar-velocity covariance by means of the statistical approach to inhomogeneous turbulence recently developed by the author. Using the expression, the mean scalar field in wall turbulence is examined to find the logarithmic scalar profile, with good agreement with experimental findings.

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The asymptotic behavior (for small Knudsen number) of the steady flow of a rarefied gas over a body with a small accommodation coefficient (of the order of the Knudsen number) is investigated on the basis of the Boltzmann-Krook-Welander equation and the Maxwell-type boundary condition. It is shown that the present results provide a bridge between the cases of zero accommodation coefficient (specular reflection) and of finite one. As applications of the theory, a sphere with constant temperature in a uniform flow of gas and that in a gas at rest with a uniform temperature gradient are considered.

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The reactions ¹²⁴Sn(p, t) and ¹²²Sn(p, p′) at 54.9 MeV have been studied using a high-resolution magnetic spectrograph “RAIDEN.” Experimental angular distributions were analyzed by DWBA calculations. The lowest 6⁺, 8⁺, 10⁺(h_11⁄2)² and 9⁻(h_11⁄2, g_7⁄2) states in ¹²²Sn were established at 2.56, 2.69, 2.78 and 3.71 MeV, respectively.

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Proceeding the previous paper (J. Phys. Soc. Jpn. 46 (1979) 1474) the high field magnetization process of Co(S_xSe_1−x)₂ system for 0.70≤x≤1.00 has been investigated by means of pulse fields up to 500 kOe at fixed temperatures. The metamagnetic behaviors were observed and the phase diagram between the transition field and temperature was given. The saturation moment seemed to disappear at x\simeq0.6.

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