A tiny persistent ring current with the electromagnetic energy of mc² can describe most of the non-wave properties of the electron accurately. Selfconsistent equations yield the radius of the ring, R₀=2(1+α⁄2π)(h⁄mc), and the g-factor of the model, g=2(1+α⁄2π). This semi-classical model has a definite advantage over the point charge model, because it includes the spin phenomena intrinsically with no divergence problem in its leading term.

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The reaction ¹²C(³He, α)¹¹C was studied at the bombarding energies of 24.0, 29.2, 34.7 and 39.6 MeV and differential cross sections were analyzed in DWBA and CCBA. The large strength of shell-model-forbidden transition to the 5/2⁻ state was found to be well explained by the multi-step processes including inelastic channels.

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The Onsager reciprocal relations can also be proved from the stand-points of the Markov process or of the kinetic theory. Their cornerstone is the principle of microscopic reversibility. However this principle represents by no means a universal rule. Furthermore the usual proof can treat only the so-called α-variables, but can not treat the β-variables rightly. In this paper we discuss the methods which do not utilize the principle of microscopic reversibility and can treat both the α- and β- variables rightly. Furthermore, we conclude that when the principle of microscopic reversibility holds, there can not exist the cross-phenomena between the α-variable and β-variable.

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The amplitude and phase fluctuations in self-excited oscillation are studied phenomenologically using a van der Pol type stochastic equation. The second-order differential equation is converted into two first-order differential equations for the amplitude and the phase and their probability distributions are derived from the associated Fokker-Planck equations. The probability distribution of the amplitude around its most probable value is anomalously broadened and non-Gaussian near threshold of oscillation. The fluctuation in the oscillatory state is rather quasi-Gaussian. The growth of the time coherence of phase above threshold is accounted for to be due to a decrease in an apparent diffusion coefficient for phase fluctuation

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A model system proposed by Maier and Saupe is treated theoretically by the method of symmetry-breaking potential. The free energy of the system is calculated up to the third-order in inverse temperature as a function of the nematic order parameter S. The first-order phase transition predicted by the Maier-Saupe theory, based on a molecular field approximation, is verified for ordinary cases of molecular configuration, namely, the simple cubic, body-centered cubic and face-centered cubic lattices. The obtained values of transition temperature T_c and S at T_c for simple-cubic lattice are nearly equal to “exact” values calculated by a Monte-Carlo method by Lasher and Lebwohl.

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It is expected that a He³ atom in solid He⁴ travels through the lattice due to the tunneling effect and behaves as a quasi-particle, “impuriton”. We calculate the spin diffusion coefficient D of impuritons, using a realistic interaction between impuritons and obtain D\simeq(J₃₄a)²⁄xV₀, where J₃₄ is the He³–He⁴ exchange constant, a the lattice constant, x the concentration of He³ impurities and V₀ the strength of the interaction. It is shown that J₃₄ is the same order of magnitude as the He³–He³ exchange constant in pure He³ solid at the same molar volume.

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The intermediate coupling theory is applied to the problem of a polaron with an anisotropic mass. The energy levels of a polaron bound in a Coulomb potential are discussed. Hydrogenic wave functions are used as variational wave functions, and it is shown that each energy level depends not only on the principal quantum number but also on the azimuthal and magnetic quantum numbers owing to the anisotropy of the mass.
The electric polarizability of a bound polaron is also calculated, and the effect of a weak magnetic field is discussed both in the absence and the presence of a Coulomb potential.

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Kittel’s free energy expression with the cross term of two sublattice polarizations was dealt with to obtain some properties of a linear antiferroelectric. Four phases, nonpolar, polar, antipolar and semipolar, are stable in proper ranges of temperature and bias field. The phase diagram was obtained by comparisons of free energy of four phases. The isothermal relation between the polarization and the external field predicted successive forced transitions and a multiple hysteresis loop. At a constant field, the antipolar-polar-semipolar-nonpolar transitions were expected at changing temperature. Correspondingly to the transition scheme, complicated behaviors of polarization, antipolarization and susceptibility as functions of temperature were calculated with bias field as a parameter.

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The level broadening and the transverse conductivity under magnetic fields of arbitrary strength are studied in the simplest approximation free from the difficulty of divergence caused by the singular nature of the system. Scatterers are assumed to be of short-range. The peak value of the conductivity associated with each Landau level decreases slowly with decreasing magnetic field. Assumption of a phenomenological constant relaxation time is not sufficient and the self-consistency is important even under rather weak magnetic fields. The oscillation of the density of states and the conductivity are numerically calculated.

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Effect of pressure on the Curie temperature has been studied in ferromagnetic compound GdZn_1−xIn_x (0≤x≤0.15) under hydrostatic pressures up to 6000 bar. Change of sign in the pressure coefficient of the Curie temperature (1⁄T_c)·(ΔT_c⁄ΔP) was found from negative (0≤x≤0.016) to positive (0.024≤x≤0.15) at x=0.02 concentration. The coefficient was −0.05×10⁻⁶ bar⁻¹ for GdZn and +2.47×10⁻⁶ bar⁻¹ for GdZn_0.85In_0.15 sample.

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The magnetic structure as well as the exchange parameters in MnGeO₃ with the ilmenite structure have been investigated by neutron diffraction and paramagnetic scattering using powder sample prepared at 1000°C under high pressure of 50 kbar. It has been found that the crystal has the same antiferromagnetic structure as MnTiO₃; the spins are directed along the [111] rhombohedral axis and are aligned in antiparallel in the layer. The nearest neighbor Mn²⁺ distance is 3.02Å and the exchange integral J₁ between them is found to be 0.84±0.01 meV.

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Large internal fields of Al³⁺, Ga³⁺ and In³⁺ substituted in NiFe₂O₄ were observed with spin echo method at 4.2 K. The fields increase rapidly with the atomic number. Contributions to the field by the A–A and B–B interactions are negligibly small in comparison with the A–B interaction. Transferred fields of these cations from Fe³⁺ and Ni²⁺ were separated. Direction of the field of In³⁺ on the A-site is parallel to the total magnetization. The results were analyzed with a simple molecular orbital method. Polarized valence orbital of the diamagnetic cations induces the field predominantly but distorted outermost closed shell also contributes considerably to the field through cross terms. Electron transfers from one 2p and 2s orbitals of O²⁻ to the cations on the A-site are 4∼6% and 0.1∼0.5% respectively and those from one 2p orbital of O²⁻ to the cations on the B-site are 10∼13%.

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The hyperfine field at Mn⁵⁵ nuclei in fcc cobalt has been measured by means of nuclear magnetic resonance in the range from 4.2 K to 296 K. It decreases much more rapidly than the saturation magnetization with increasing temperature as the hyperfine field at Mn⁵⁵ nuclei in iron.

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It is shown that the density-matrix can be used to calculate the Knight Shift. The calculations for Mg, Al and In, using a model local pseudo-potential are in reasonable agreement with experiments. It is hoped that the method will be of use in disordered systems.

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The ferromagnetic anisotropy energies of Ni and Fe metals are calculated based on the differences between the crystal energies with the different directions of the spontaneous magnetization. These crystal energies are calculated by taking into account the variations of the spin-orbit interaction and the magnitude of the spontaneous magnetization, on the basis of the energy bands of ferromagnetic Ni and Fe metals, where the redistribution of the conduction electrons for each direction of the spontaneous magnetization is also taken into account. The obtained results are in agreement with the experimental results. The doubly degenerate energy levels in the energy bands, intersecting the Fermi level, produce the dominant contributions to the anisotropy energy. In Ni metal the temperature dependence of the anisotropy constants can be explained by the temperature variation of the Fermi level, and for Fe metal it can be explained in consideration of the decrease of the exchange splitting.

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The ferromagnetic anisotropy energy of H. C. P. Co metal is calculated by the use of the energy bands of ferromagnetic Co metal given by Ishida. The doubly degenerate energy levels along [0001] axis on the Brillouin zone produce the contributions to make c-axis to be the easy axis. The other doubly degenerate energy levels and the approaching energy levels produce the contributions to make c-plane to be the easy direction. It is shown that at 0 K, c-axis is the easy axis, and when the temperature is raised and the exchange splitting decreases, c-plane becomes the easy direction. The anisotropy energies of Co alloys including 1 at% of Fe and Ni metal are also calculated. The obtained results are in agreement with the experimental results.

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The energy bands for d electrons in the double hexagonal structure are calculated in the tight binding approximation, including the spinorbit interaction. The anisotropy constants for the double hexagonal Co–Fe alloy are calculated on the basis of these energy bands. The easy axis is in the c-plane. These obtained results are in agreement with the experimental results. It is shown that the energy bands for the double hexagonal structure there exist the double degenerate energy levels along [0001] axis in the Brillouin zone but these energy levels do not intersect the Fermi level in this alloy, and some approaching energy levels apart from the [0001] axis intersect the Fermi level and produce the contributions to make the easy axis to be in the c-plane.

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Measurements of the pressure-temperature variations of the electrical resistivity were made on the antiferromagnetic α-Min and the α-Min_0.92Fe_0.08 alloy from 4.2 K to room temperature and up to about 8 kbar. The pressure coefficients of the residual resistivity, the spindisorder resistivity and the Néel temperature T_N are estimated. The pressure dependence of the resistivity is discussed in terms of the magnetic superzone boundary effect based on the RKKY mechanism. It is suggested that the resistivity is enhanced by about ten times larger than that in the absence of the magnetic gaps at absolute zero temperature for pure α-Min. The pressure dependence of T_N is also discussed with the RKKY interaction, comparing to the variation of T_N with the electron-atom ratio at atmospheric pressure.

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We calculate the spin-lattice relaxation time in solid He³ with He⁴ impurities in the low temperature region where the bottle-neck is between the exchange and the phonon bath. The tunnelling of He⁴ atoms and the interaction between them due to lattice deformation are taken into account. We regard our system to consist of the exchange-tunnelling, the He⁴–He⁴ interaction and the phonon bath. It is shown that the first two baths are in equilibrium with each other in the relaxation process. The mechanism of relaxation involving the tunnelling of He⁴ leads to T₁ proportional to T⁹. The concentration dependence of T₁ can be explained by the increase of the heat capacity of the interaction bath.

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Phosphorescence emission its decay time in platinum phthalocyanine (PtPc) single crystals were investigated in the near infrared region around 971 nm by Q-switched ruby laser. The intensity of phosphorescence emission around 971 nm at 4.2 K tends to saturate and its decay time begins to decrease with increasing excitation intensity above the incident photon flux of 1×10²³ photons/cm²sec. These dependence are explained in terms of triplet exciton-triplet exciton (T–T) collision. Assuming that all the excited singlet excitons are converted to the triplet exctions and the absorption coefficient of the ruby laser light is 10⁵ cm⁻¹, the value of the bimolecular quenching rate γ is estimated to be about 1×10⁻¹⁶ cm³/sec.

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The X-ray photoelectron spectra of the valence bands in CuAlS₂, CuGaS₂, CuInS₂, and AgGaS₂ have been measured. The spectra show that the upper parts of the valence bands in the Cu-compounds and the lower part of the valence band in the Ag-compound are mainly composed of d states of the monovalent metals. The spectra have been deconvoluted with a measured instrumental response function. The deconvoluted spectra of the Cu-compounds show almost d-like bands whose locations well agree with those obtained from the optical study by Shay et al. Resemblance between the valence bands of the Cu-compounds and those of cuprous halides is pointed out. In the deconvoluted spectra of CuAlS₂ and CuGaS₂, peaks which may be due to the states of the trivalent ions are found in the high-binding-energy parts.

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The lattice attenuation factor α₁ in CdS is studied experimentally by a double-pulse method and theoretically, mainly concentrating on the non-linear effect between various frequency components. The agreement between experiment and theory is very good. Under the strong flux condition (10⁷∼18⁸ times as large as the thermal level), the frequency dependence of α₁ in the range between 200 MHz and 2.5 GHz is expressed by ω^1.0 deviating largely from the Akhieser ω^2.0-law, and in the weak flux case (10⁶∼10⁷ times), it is approximately by ω^1.8 slightly differing from the ω^2.0-law. The deviations from ω^2.0-law are due to the energy up-conversion from low frequency to high frequency components. The quantitative computer analysis shows that the non-linear effect due to usual lattice anharmonicity is rather important in comparison with effective anharmonicity with electrons (Hutson mechanism), in the above frequency range.

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The optical absorption spectra of purified TlCl and TlBr have been investigated near the band edge. It was found that the absorption rises as a three half power of the energy near the edge and as a cube of the energy in the high energy region. It is concluded that the edge is due to the creation of the is indirect-forbidden exctions of X₆⁺×R₆⁻ and the lowest minimum in the conduction band is at the R-point. Theoretical calculation of an indirect-forbidden exciton transition is made. The result is different from what has been proposed by the previous works, but it describes well the experimental results. The binding energy of the indirect-forbidden exction in TlBr is determined as 23±5 meV.

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Low level absorption spectra at the edges of TlCl(I), TlBr(I), TlCl(Br) and TlBr(Cl) mixed crystals are measured. At the low concentration of minority halogen, the absorption peak originated in the localized level due to iodine is found in TlCl(I) while the disorder-assisted zero-phonon X₆⁺×R₆⁻ exciton absorptions are observed in TlBr(I),TlCl(Br) and TlBr(Cl). Above the critical concentration of the minority halogen, a long tail associated with the bound states due to the cluster formation appears. The absorption is analyzed and the growth of the long tail is discussed.

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Quantized surface states in an inversion later of narrow-gap semiconductor with the zinc-blend structure are investigated theoretically by the effective mass approximation for nearly degenerate bands. When the band gap is small, and the spin-orbit interaction is large, the inversion asymmetry of surface potential causes large k-linear term in the two dimensional dispersion relation, which removes the spin degeneracy. Also, the g-factor becomes so large that the reversal of the ordering of the Landau levels is expected. The theory is applied to the analysis of the Schubnikov-de Haas measurements of Hg_0.79 Cd_0.21Te (ε_G=68 meV, m₀^*=0.006 m). The inversion asymmetry splitting of the spin degeneracy is as large as several meV, and the inversion in the order of Landau levels is expected to be observed. The surface potential of the sample is expressed in the parametrized form, and values of the parameters are estimated by using the experimental data.

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X-ray photoemission spectra have been measured of the 4d and 3d shells of La³⁺ and Ce³⁺ in La- and Ce-halides. The results, particularly in the case of the spectra of the 4d level, show a marked dependence of spectral profile of halogen. The existence of the satellite accompanying the 4d_5⁄2 and 4d_3⁄2 components is shown by an analysis of the spectra obtained by deconvolution of the raw data of La-halides. The halogen dependence of the spectra is ascribed to the simultaneous charge transfer transition from the valence level of ligand to the unoccupied 4f level of the metal ion as being the origin of the satellite.

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Absorption bands have been found at 655 nm, 830 nm and 1.28 μm in ZnS:Mn crystals under optical excitation. From the close correlation to the orange fluorescence in the time behavior and exciting power dependence, the initial state of these transitions is identified with the emitting state ⁴T₁(⁴G) of Mn²⁺ ion. Comparison of the energies between the experiment and calculation leads to the assignment of the terminal levels as ⁴A₂(⁴F), ⁴T₁(⁴P) and ⁴E(⁴D) states, which is consistent with the strengths and breadths of the observed transitions. From the energy position of the 1.28μm band, it is concluded that the excitationinduced absorption initiates from the relaxed excited state. It is also shown that both single Mn²⁺ and exchange-coupled pair of Mn²⁺ and exchange-coupled pair of MN²⁺ contribute to the excited-state absorption.

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A working hypothesis is proposed for explanation of peculiar behaviors in Ca₂Sr(C₂H₅CO₂)₆ (DSP) observed with respect to its ferroelectric phase transition. On the basis of consideration of crystal structure it is pointed out that the Mitsui theory for Rochelle salt is applicable to DSP, and strain in the ferroelectric phase is discussed.

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Changes of the splitting between two absorption-lines corresponding to transitions from two Kramers doublets of ⁴A₂ to the excited Kramers doublet Γ₇{²E(²D)} induced by applied uniaxial stress P, are investigated by using P up to 2.5 k bar at 4.2 K. It is estimated from the experiment that the splitting of ⁴A₂ will become zero, i.e., the [CoX₄]²⁻ complex-ion will be reformed to the regular tetrahedron, at |P|=|P_c|=7.57±0.1 k bar and 8.78±0.1 k bar for Cs₃CoCl₅ and Cs₃CoBr₅, respectively, when P is perpendicular to the c-plane. The initial tetragonal distortion Δθ_i of the [CoX₄]²⁻ complex-ion estimated from this result, Δθ_i(P_c), is consistent with the X-ray data for Cs₃CoCl₅. Δθ_i(P_c) is also consistent with Δθ_i calculated from the initial splitting of ⁴A₂ for both compounds. The contribution of the Jahn-Teller coupling to Δθ_i is estimated from the experiment as small as 3∼4% of Δθ_i for both compounds.

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An analysis of dependences of the splitting of ⁴A₂ on applied uniaxial stress P, which have been measured by authors in four experimental arrangements, P⊥(001), P⊥(100), P⊥(110) and P⊥(11 a⁄c), is presented. Experimental results can be explained by strains of the [CoX₄]²⁻ complex-ion calculated by taking account not only of stiffness of the complex-ion, but also of an effective force acting on the complex-ion itself, which is obtained experimentally from shifts of the average transition energy of spectra ⁴A₂→²T₂(²D) induced by P. It is shown that the Jahn-Teller coupling constant V_θ^JT with the ε-mode can be estimated not only from the effect of uniaxial stress, but also from the initial tetragonal distortion Δθ_i of the complex-ion. V_θ^JT in ⁴A₂ estimated from two procedures agree with each other. The pseudo Jahn-Teller effect is expected from Δθ_i to be effective in some of excited states such as ²E(²D), ²T₂(²G), etc., of both compounds.

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Shifts of the average transition-energy E_av of spectra ⁴A₂→²E(²D) and ²T₂(²D) induced by applied uniaxial stress P, ΔE_av⁄|ΔP|, are investigated by using P up to 2.5 kbar at 4.2 K. Spectra ⁴A₂→²E(²D) of Cs₃CoCl₅ exhibit a small blue-shift, while those of Cs₃CoBr₅ exhibit a large red-shift. This is explained by the difference mainly in (ΔB⁄B₀)⁄(ΔR⁄R₀) between two compounds, where B₀ is B for a free Co²⁺ ion and ΔB is the change of B induced by that of the coordination-bond length R₀, ΔR. ΔE_av⁄|ΔP| of two spectra ⁴A₂→²E(²D) and ²T₂(²D) gives nearly the same value of (ΔB⁄B₀)⁄ΔR⁄R₀), i.e., 1.38±0.15 for Cs₃CoCl₅ and 2.20±0.15 for Cs₃CoBr₅. On the other hand, values of B and R₀ in excited cubic-field terms are determined from absorption-energies of zero-phonon lines and from absorption-intensities of vibrational site-lines, respectively. (ΔB⁄B₀)⁄ΔR⁄R₀) obtained from this procedure agrees with (ΔB⁄B₀)⁄ΔR⁄R₀) obtained from ΔE_av⁄|ΔP|.

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The dispersion relations in CaWO₄, CaMoO₄, SrMoO₄, BaWO₄, BaMoO4, NH₄ReO₄ and ND₄ReO₄ are determined from the two possible sets of force contants given in J. Phys. Soc. Japan 36 (1974) 511 and 916; the words, case I and II, were used to distinguish the two sets of the constants. The sets corresponding to the case II are not suitable to the two perrhenates, as they give imaginary frequencies. The elastic-wave velocities are determined as the gradients of the dispersion relations of the acoustic branches at k=0. The comparison of the theoretical velocities with the observed values suggests that the set corresponding to the case I is reasonable for CaMoO₄.

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The negative ENDOR technique was used to study a C–H radical (center #2) in an X-ray irradiated crystal of ferroelectic Rochelle salt. Within the 8–20 MHz frequency range, signals from at least 11 different types of protons were detected. It was shown that a group which is broken from a tartrate molecule upon irradiation is trapped in the immediate vicinity of the damaged molecule. This result suggested that center #2 is an electrically charged paramagenetic species, rather than a simple radical as previously surmised.

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The ³⁵Cl nuclear quadrupole resonance frequencies and relaxation times in ammonium hydrogen bis (chloroacetate) were measured in the ferro- and the paraelectric phases. The splitting of the resonance line in the ferroelectric phase shows the temperature dependence in the form of Δν=(T_c−T)^1⁄3 near the transition point T_c. Sharp decrease of T₁ has been observed in the critical region and it was attributed to the critical slowing down of the electric dipolar interactions. Two kinds of relaxation mechanisms were examined: The order-disorder type of mechanism can explain the T₁ data of the paraelectric phase but it fails to explain the different temperature dependence of T₁ of ν₁ and ν₂ in the ferroelectric phase. The other mechanism, the displacive-mode transition is plausible because it gives a reasonable description of the T₁ anomaly both in the ferro- and paraelectric phases. This mechanism is also consistent with the structural evidences.

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Structural phase transitions in perovskite-type CsPbBr₃ have been investigated by neutron diffraction method. Phase transitions occur at 88°C and 130°C, which are respectively second and first order. The phase transition at 130°C is caused by condensation of the M₃ mode at the M point of the cubic Brillouin zone, while the one at 88°C results from condensation of the doubly degenerate R₂₅-like mode (Z₉ mode) at the Z point of the tetragonal Brillouin zone. Group theoretical considerations based on these results reveal that the crystal trans-forms from cubic perovskite structure (O_h¹-Pm3m) to tetragonal D_4h⁵-P4⁄mbm at 130°C and further to orthorhombic D_2h¹⁶-Pmbn at 88°C. Possible atomic displacements induced at the phase transitions are obtained from the eigenvectors of the condensing modes.

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Raman and infrared activities and splitting features caused by the perturbations of [0, 0, 1], [1, 1, 1] and [1, 1, 0] electric fields are tabulated. As all of the field-perturbed two-phonon processes are Raman active, splitting features and polarization dependences may be useful for the interpretation of spectra. Most of the infrared inactive two-phonon processes are ralaxed into active. The observation of infrared peaks is expected in high frequency region where few field-free peaks have been observed.

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A coherent superposition state of 5S and 5D levels of Rb vapor, when it was excited by two-photon resonant transition between these levels, was observed by applying an interrogation pulse which was non-resonant to the system. The emphasis is laid on this coherence in the atomic excitation, instead of just the population inversion, in explaining the origin of various strong collimated emissions observed by many authors. Saturation of the off diagonal density matrix element between 5S and 5D levels was observed at higher excitation level due to the population change. An analysis of the saturation is given using a simple model for the coherence of the dye laser beam.

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A statistical mechanical theory of entanglement is developed, based on the topology of loops. As the simplest example of entangling systems, a system composed of a polymer chain and a fixed barrier is studied in the present and in the two following papers. First, Gauss linking coefficient T is given for simple-square-lattice chains, and it is transformed, basing on the periodicity of the polymer chains, into “topological variables T_α,” which describe corrective motions of the entangling polymer chains. The Verdier-Stockmayer model is used as a model of the Brownian motion of polymer chains. A diffusion equation is derived for a simultaneous distribution function in regard to a few topological variables T_α and a few “normal coordinates Q_α”. The diffusion equation is farther transformed to describe an evolution of small fluctuations of T_α and Q_α around their equilibrium values.

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In the previous paper, a system composed of a polymer chain and a fixed barrier has been studied and a diffusion equation has been derived for a simultaneous distribution function in regard to a few normal coordinates Q_α and a few topological variables T_α. In this paper, the following are given: (i) The nature of the diffusion equation is examined qualitatively and it is shown that the entanglement effect on the motion of the center of mass of the polymer chain is caused by fluctuations of the topological variables T_α² around their equilibrium values, (ii) an average force acting an the center of mass is calculated exactly along its fixed trajectory and an expression of frictional coefficient ζ of the center of mass is derived. Numerical calculations of ζ are given in the following paper.

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Explicit expressions of γ_α², d₀ and δ_α are derived and they are computed numerically as functions of N, the polymerization number and r, the distance between the center of mass of a polymer chain and a fixed barrier. The frictional coefficient ζ of the center of mass is also computed as a function of N and r based on the expression derived in the second paper of this series and it is shown that ζ of an entangling polymer chain takes, at (Remark: Graphics omitted.), its maximum value which is 20∼50% larger than that of a “free” chain.

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To examine the possibility of the formation of carbonium ion in visual pigment, the λ_max, π-electronic structure, total ground-state energy and adiabatic potentials for cis-trans isomerization are calculated for the carbonium ion of the unprotonated Schiff-base of retinal or retinal₂. The calculations are carried out according to the previous formulations and parametrizations contrived to study protonated retinal Schiff-bases. It is shown only the case of retinal₂ where Lewis acid adds to C₁₄ can exhibit its λ_max in the observed range of λ_max for visual pigments but is contrary to the photoisomerization known to occur from the 11-cis to the all-trans form.

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One-dimensional similarity solutions are applied to the shock and expansion waves which are induced in the target plasma exposed to a high-power-laser radiation. It is pointed out that ions in the shock-heated plasma and those in the expansion wave, respectively, correspond to the “fast ions” and “slow ions” detected in the experiment. Taking account of the anomalous absorption of the laser energy in the target plasma, we derive a relation T_e∝P_l^4⁄3 between the electron temperature T_e and the energy intensity P_l of the incident laser light.

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Two-dimensional steady viscous incompressible fluid flow past an arbitrary cylindrical obstacle is treated, and a method to find a numerical solution is given. By an application of conformal mapping, the problem is reduced to a boundary value problem of partial differential equations on a rectangular domain. Its difference analogue is solved on a digital computer. In the case where the outside of the obstacle cannot be conformally mapped onto an elementary function, the mapping function in constructed by finite-difference method. Some results of numerical calculations are reported for the cases where the obstacles have oval shapes, the Reynolds numbers being 10 and 31.

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This paper deals theoretically with a flow of a grey radiating gas induced by buoyant force in a semi-infinite space bounded by a flat plate, which is parallel to the direction of the gravity, An external beam radiation is imposed normally through the transparent plate. The gas is assumed to be viscous, non-heat conducting and to have constant physical properties. The radiation field is assumed to be in local thermodynamic equilibrium. The case is considered that the temperature and the flow velocity are uniform in a region away from the plate. The solution is obtained by method of matched asymptotic expansions. A steady flow is obtained in which the buoyant force balances against the viscous force. The flow is induced not only in the neighbourhood of the plate, but also in a region away from the plate, though the temperature change is localized in the former.

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