The gamma-ray energies and relative intensities of 38 gamma transitions in ¹³¹Cs following the decay of ¹³¹Ba have been precisely measured. The gamma-ray transitions of energies 128.2, 351.19, 369, 546.3, 795.7, 797.39, 919.5 and 954.66 keV and the energy levels at 919.5 and 1170.70 keV in ¹³¹Cs have been confirmed. Gamma transitions of energies 82.40, 323.9, 462.87, 508.0, 563.4, 703.42, 1046.9, 1125.94, 1170.5, 1208.7 and 1341.85 keV and an energy level at 1341.98 keV reported earlier could not be observed in the present measurements. In addition, gamma-gamma angular correlation measurements for four cascades in ¹³¹Cs have been carried out. The spin assignments 5/2⁺ and 3/2⁺ have been made to the 123.85 and 620.13 keV levels in ¹³¹Cs respectively. Also, the multipole admixtures in the 404.03, 496.30, 831.61 and 923.85 keV transitions have been measured. A comparison of transition probabilities of various transitions in ¹³¹Cs has been made with single particle estimates.

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Measurements on the longitudinal polarization of β-ray emitted from ¹⁴⁷Pm at low energies v⁄c=0.41, 0.5 and 0.6 have been carried out. The polarization P was obtained by Mott scattering at an angle of 75° after it had been transformed from longitudinal to transverse polarization by an electrostatic rotator. The measured values of the rolarization were −(1.028±0.132)v⁄c, −(0.898±0.029)v⁄c and −(0.932±0.047)v⁄c for the energies v⁄c=0.41, 0.5 and 0.6, respectively. Overall feature of the present results is consistent with the prediction by the two component neutrino theory.

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The decay of Ag^110m to the levels of Cd¹¹⁰ has been investigated to verify the existence of some weak gamma transitions reported earlier. The energy and relative intensity measurements for all the gamma transitions have been done. Previously reported γ-transitions of energy 264.25, 341.19, 356.24, 409.32, 572.7, 603.0, 630.61, 676.6, 708.115, 774.8, 1186.7, 1572.3, 1629.65 and 2004.7 keV have not been observed while the 360.7, 466.9, 493.8, 544.8, 957.3, 1125.7, 1163.5, 1165.6, 1251.2, 1300.0, 1592.8, 1775.6 and 1783.4 keV transitions have been confirmed. As a consequence of these measurements, levels at 2078.804, 2287.41 and 2662.51 keV have been discarded.
Gamma-gamma directional correlation measurements have been done on 24 cascades and the multipole admixtures for 12 gamma transitions have been evaluated. Large M1 admixture is found in 2₂⁺→2₁⁺ and 4₂⁺→4₁⁺ transitions.

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The level scheme of ¹⁰³Ru has been studied in the β decay of ¹⁰³Tc with γ-ray singles and γ-γ coincidence measurements. The decay scheme which consists of 18 levels involving 53 γ transitions was constructed. The logft values were determined based on γ-ray intensities and β feedings to the ground and first excited states. The level properties of ¹⁰³Ru are discussed.

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The 1⁺ isomer in ²⁴Al is found to be located at 426 keV slightly different from the previous assignment. The 1⁺ isomer decays by β transitions with branching ratio of 22±3% and by emission of a 426-keV γ ray with 78±3%. The log(ft) value of the β transition from ^24mAl(1⁺) to the 9962-kVe level in ²⁴Mg is obtained to be 3.5±0.1, indicating a super-allowed transition. The reduced transition probability B(M3) of the 1⁺→4⁺ γ transition is deduced to be 264±13(eh⁄2Mc)²fm⁴. Correction for spin magnetic moments in M3 moments are discussed.

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We present results of a Monte Carlo simulation of the time evolution of the ordering process in an f.c.c. A₃B alloy, which undergoes the order-disorder phase transition. In our model system, nearest neighbor interactions are assumed to favor pair formation of A and B atoms. A and B atoms are initially arranged randomly on the f.c.c. lattice sites, then the system is quenched to and to be evolved at a finite temperature T. Exchanges of position of atoms are allowed between nearest neighboring atoms with the Markovian transition probability.The time variations of the distribution function of cluster size and the average value of cluster size are obtained. These are compared with the results obtained from X-ray diffraction studies. Near the transition temperature, the relaxation time for the number of ordered cells shows a kind of slowing down behavior.

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All the energy eigenvalues of the Hubbard model with infinite repulsion on 2×2×2 cubic lattice for different electron numbers N_e are calculated numerically. For N_e=4, 7 the ground state is completely ferromagnetic; namely, total spin S is N_e⁄2. For N_e=5, the total spin of the ground state is 3/2. For N_e=2, 6, it is zero. For N_e=1, 3, it is 1/2. Thermodynamic quantities such as entropy, susceptibility and specific heat are calculated with the method of canonical ensemble. There are two peaks in the specific heat curve for N_e=4, 5, 6, 7, but only one peak for N_e=1, 2, 3.

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A phase transition is studied for a quenched random bond mixture of classical Heisenberg ferro- and antiferromagnets on a triangular cactus tree. The transition temperature to the random ordered phase is obtained by the effective Hamiltonian method. Because of the rotatability of the classical Heisenberg spin, infinitely degenerate canted-spin-arrangements appear in the ground state, which are in contrast to the Ising model. The dependence of the transition temperature on the concentration of ferromagnetic bonds agrees qualitatively with those for the Ising model.

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The magnetic susceptibility and its field dependence measurements are carried out of a nearly two-dimensional antiferromagnet CaCu(CH₃COO)₄·6H₂O, along the many directions, below the Néel temperature (T_N=30.1±0.5 mK). In the field dependence experiments, a peak value of magnetic susceptibilities appears below T_N, at about 700 Oe for the directions in c-plane, at about 500 Oe for the c-axis direction, respectively.

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Measurements of magnetization and susceptibility have been made on single crystals of heavy rare earth copper compounds, RCu₂. All these compounds show metamagnetism with a relative low critical field at 4.2 K. The paramagnetic Curie temperatures along each principal axis are anisotropic. The crystal field parameters V₂⁰ and V₂² are determined from the values of anisotropic paramagnetic Curie temperatures on the basis of the molecular field theory. These values are in agreement with those evaluated from a point charge model. The neutron diffraction measurements on a TbCu₂ single crystal confirm the collinear magnetic structure.

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Measurements of magnetization and susceptibility have been made on light rare earth-copper intermetallic compounds, RCu₂. The NdCu₂ compound shows antiferromagnetism at low temperatures but CeCu₂ and PrCu₂ compounds show no magnetic ordering down to 4.2 K. In the paramagnetic region, the susceptibility for PrCu₂ and NdCu₂ compounds obeys the Curie-Weiss law and there is a large anisotropy in the paramagnetic Curie temperature along the three principal axes. The crystal field parameters V₂⁰ and V₂² of PrCu₂ and NdCu₂ compounds are determined from the values of the anisotropic paramagnetic Curie temperature.

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A single crystal of Fe₂TiO₄ was grown with an infrared ray image furnace and its magnetization and Mössbauer srectra were measured. In a specimen squeezed along [001], we found that, at 77 K, the tetragonal axis and the spontaneous moment are fixed along [001], with a slight deviation in (110) or (1\bar10) plane (about 10∼20°) for the moment. In Mössbauer measurement, it was observed that the sharpness of the spectrum was largely affected by the domain distribution. We found several peaks which is ascribed to a special group of Fe²⁺ ions. We conclude that the E.F.G.Z axis of these Fe²⁺ ions is vertical to the hyperfine magnetic field H_n and they are on B sites with 3d electron orbitals spreading like that of dε_yz or dε_zx.

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Thermal expansion coefficient of Fe–Ni Invar alloys at low temperatures has been examined by using the itinerant electron model. It has been found that the experimental values obtained by Schlosser et al. and by Zakharov and Fedotov could be explained satisfactorily up to about 200 K by using the expression derived in the present paper which has three terms, the normal lattice term, the spin wave term which is proportional to T^1⁄2 and the single particle excitation term proportional to T.

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The magnetic structures of the GdCu_1−xZn_x system have been studied by epithermal neutron diffraction and magnetization measurements. The antiferromagnetic (π, π, 0) order was detected in GdCu_0.45Zn_0.55 below 50 K, above which a superparamagnetic behavior appears. GdCu_0.35Zn_0.65 is almost ferromagnetic, but an inhomogeneous canting of the spin is anticipated at low temperatures. The magnetic phase diagram is distinctly different from that of the Tb(CuZn) system.

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Tricritical point (TCP) of a dilute metamagnet is investigated by the Takagi approximation on the basis of Ising meta-model. It is shown that the tricritical temperature decreases when the system is diluted by non-magnetic atoms, and becomes zero at the concentration c_p, which coincides with the critical concentration of a ferromagnetic plane in the same approximation, despite of essentially three-dimensional nature of the metamagnetic transition. It is also shown that, in contrast to the tricritical temperature, the tricritical field tends to a finite value with dilution.
The results obtained agree qualitatively with the magneto-optical study of dilute metamagnet Fe_cMg_1−cCl₂ by Wood and Day.

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An expression of the exchange stiffness constant of spin waves in disordered ferromagnetic alloys is obtained in the combined approximation of the random phase approximation and the coherent potential approximation. Both the diagonal randomness and the off-diagonal randomness are taken into account. By using the realistic band structures, the exchange stiffness constants in fcc Fe–Ni alloys are calculated numerically. The difference between the observed and calculated values of the exchange stiffness constants in fcc Fe–Ni alloys is attributed to the inter-atomic exchange interaction between d-electrons.

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The magnetic susceptibilities of molten Ge–Te and Sn–Te alloys have been measured as a function of concentration and temperature. Curves of the isothermal susceptibilities for Sn–Te system show a large deviation from the linearly interpolated ones at the composition near Sn₅₀Te₅₀. On the contrary for molten Ge–Te system a rather small deviation is found around 45 at% of Te. From these results, the electronic state and chemical bonding in liquid IV–Te system are discussed in comparison with those in liquid IIIb–Te system.

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The recovery process of deuterium dissolved in excess in nickel was studied by means of the liquid hydrogen quenching and electrical resistivity measurement developed by the author. The diffusion coefficient of deuterium was determined as D=3.18×10⁻³ exp (−9220⁄RT) cm²/sec between 220 K and 340 K, and compared with that of hydrogen in the temperatures where the isotope effect was expected to appear remarkably.
The obtained results on the pre-exponential factors, D_o’s, and the activation energies, E’s, showed the relations, D_oH<D_oD and E_H<E_D, respectively, which looked abnormal from the view point of the classical diffusion theory. The ratio, D_H⁄D_D, was always larger than 1.0 and increased with decreasing temperature, differing from the simple extrapolations of the results by other investigators, in which the ratio decreased below 1.0 with lowering temperature. The above isotope effects in hydrogen diffusion cannot be explained by the existing theories of diffusion regardless of harmonic or anharmonic treatment.

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The Compton profiles of lithium and sodium in both liquid and solid states have been measured using 59.54-keV γ-rays from 1Ci²⁴¹Am. A clear difference of the Compton profile between the liquid and solid states has been found in lithium and sodium, respectively. The experimental Compton profiles corrected for the multiple scattering are compared with various theoretical profiles of these elements in both liquid and solid states.

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Compton profiles of liquid and crystalline aluminum metal have been measured using 59.54 keV γ-rays emitted from ²⁴¹Am and Ge(Li) solid state detectors. The difference of the Compton profile between the liquid and crystalline aluminum has been found and can be qualitatively understood in terms of the change in the electronic density upon melting. The experimental profile of crystalline aluminum is in good agreement with the result of the LCAO band calculation, while the profile of liquid aluminum is in poor agreement with the free electron model and the Green function method.

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Far-infrared absorption spectra in As- or Sb-doped germanium in the intermediate impurity concentration range have been investigated at 1.5 K. A steep rising of the absorption toward higher energies is found in the spectra, and their energies are closely connected with the thermal activation energies ε₂’s which are determined by simultaneous measurements of the D.C. resistivity. The concentration effect and [111]-uniaxial compressive stress effect have shown that the absorption is attributed to the electronic transition from the impurity ground states to the upper Hubbard band. The evidence of the variable-range hopping is obtained from the shape of the tail of the spectra.

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Magnetoresistance (MR) anisotropy measurement previously performed at room temperature for 1–2 μm thick p-type (001) silicon on sapphire (SOS) has been extended down to 77 K. In order to explain these anisotropies, the valence band structure is numerically calculated by the k·p method along with deformation-potential-constant formalism assuming the lateral compressive strain (∼4×10⁻³) in silicon. In the four ⟨110⟩ directions for the upper strain-split m_J=±3⁄2 band, the derivative (dE⁄dk²) becomes very small at hole energies above ∼10 meV, resulting in a tetragonally-warped, constant-energy surface with four long ⟨110⟩ protrusions, which may be responsible for room-temperature “four ⟨110⟩-ellipsoid-like” MR anisotropies. Although low-temperature MR anisotropies cannot be explained in terms of the low-energy ellipsoid, the high hole mobility which exceeds the electron one (A. C. Ipri: Appl. Phys. Lett. 22 (1973) 76) may be due to rapid decrease of hole effective mass to the ellipsoidal one.

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Measurements of the thermal expansion coefficient and the dielectric constant have been made for the uniaxial ferroelectric triglycine sulfate (TGS) along the ferroelectric b-axis. Deviations from Landau-like behavior are observed in the vicinity of the critical temperature. Some attempts of logarithmic corrections to these results are made on the basis of the Larkin-Khmel’nitskii prediction. The parameters in the theory are determined by examining the dielectric constant for clamped crystal and the thermal expansion coefficient. Agreement between the theory and the present experiments are good over the temperature range T−T_c\lesssim3 K in the paraelectric phase.

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Deuteron magnetic resonance study of RbD₃(SeO₃)₂ was made between −165 and 14°C. Electric quadrupole coupling constants and directions of the principal axes of EFG tensors were obtained in the paraelectric phase. There are three types of hydrogen bonds with different behavior which play some roles at phase transition. The relation between the temperature dependence of the resonance spectra and that of doubly degenerate soft-mode is discussed.

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Microwave conductivity σ_⊥ perpendicular to the b axis of crystalline (SN)_x has been estimated by the cavity perturbation method in the skin-depth regime to be about 40 Ω⁻¹cm⁻¹ which increases with decreasing temperature monotonously, contrary to the case of dc measurement. This fact indicates that σ_⊥ is strongly influenced by the inter-fiber barrier and the intrinsic conductivity anisotropy in a fiber is much less than that estimated by dc method in bulk material. From the normal positive magnetoresistance observed either above 77 K or even below 4.2 K at higher magnetic fields (>30 kG), carrier mobilities along the b axis and perpendicular to it are estimated to be about 250 and 6 cm²/Vsec, respectively, at 290 K. Negative magnetoresistance observed below 4.2 K at the magnetic fields below 30 kG is discussed in terms of the spin dependent scattering of carriers in connection with the appearance of the resistance minimum. Experimental data on Hall effect of crystalline (SN)_x is also discussed.

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A trapping process of vacancies by foreign atoms in fcc crystals after quenching is examined as a relaxation process of a spacial distribution of vacancies. The distribution of vacancies is constructed on a coarse-grained lattice, and its evolution is described by Markov chains. A relaxation time of the system is calculated as a function of annealing temperatures and binding energies between a foreign atom and a vacancy, and is compaired with that calculated from the rate equation of Damask and Dienes type. The relation between the relaxation time and the trapping time is discussed. It is also shown that this model yields, in a stationary state, the same conclusion derived from a usual thermodynamical formula.

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Formation times of F centers (τ_F) and self-trapped excitons (τ_STE) in RbBr crystals have been measured under the excitation by two photon absorption of second harmonics from a mode-locked ruby laser. Such excitation produces the 2p hot exciton directly in the crystal. τ_F is 27±8 ps at RT and 30±8 ps at LHeT. τ_STE is not explicitly observed, but appears to be around 30 ps. Absorption spectra measured at about 100 ps after the excitation coincide to that of the conventional F band at RT, and consist mainly of the F band and of a small contribution of the self-trapped excitons at LHeT. τ_F at RT and τ_STE at LHeT in RbI are both 30±10 ps. Possibly τ_F in KBr at RT was 20±10 ps, but the absorption decayed with a time constant of 800±200 ps. The relaxation process of the 2p hot exciton in RbBr is discussed in connection with the formation of self-trapped excitons and F centers.

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The internal friction of pure NaCl crystal has been measured to study the processes of pinning and unpinning of point defects around a dislocation. The specimens were prepared by cleaving. They were compressed about 1.5% at room temperature after annealing at 700°C for 10 hours, and then used as the specimens. The measurements have been carried out on both pinning and unpinning processes by the Marx’s oscillator method using an automatic control circuit. The results indicate that the number of pinners on dislocation increases or decreases proportionally to 1/3 power of time with the activation energy, 0.25±0.05 eV, in both processes. On the basis of calculation on the defect distribution around a vibrating dislocation, the t^1⁄3 dependence is quantitatively explained.

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We report here the dependence on hydrostatic pressure up to 2.79 kbars of the two structures associated with the A₁ and A₂ transitions in the reflectivity spectra of graphite measured at room temperature in the photon energy range from 0.655 to 1.125 eV. By considering explicitly the effect of the trigonal warping upon the probabilities of these transitions, their spectral shapes are shown to be a step and a peak, respectively, resulting in new locations of critical points on the spectral features A₁ and A₂ which are different from those previously given by Bellodi et al. The observed shifts of these structures due to pressure provide the first direct experimental determination of the fractional change per unit pressure increment of the Slonczewski-Weiss-McClure band parameters γ₁ and γ₅, yielding values of ∂ ln γ₁⁄∂p=0.028±0.003 (kbar)⁻¹ and ∂ ln γ₅⁄∂p=0.055±0.016 (kbar)⁻¹.

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The dielectric constant and the reflectivity of graphite under hydrostatic pressure are calculated in the photon energies from 0.6 to 1.0 eV. The Slonczewski-Weiss-McClure band model is employed together with the pressure derivatives of the band parameters given by Nagayoshi. The calculated lineshapes of the change of optical constants due to pressure are in good agreement with the observed ones by Misu et al. The trigonal warping in the band structure is found to play an essential role in the appearance of van Hove singularities in the joint density of states as well as in the determination of optical transition probabilities. It is also shown that the band parameter γ₁ and its pressure derivative give the dominant contribution to the position of structures and their pressure dependence in the optical constant spectra in the near infrared range.

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Chaotic fields in a general class of one-dimensional optical cavity having output coupling is considered. The fluctuation-dissipation theorem is derived assuming that the cavity materials are lossless. The cavity admittance probed by a prescribed current source for an arbitrarily stratified optical cavity is calculated and using the explicit expression for the admittance the “dissipation” is proved to be equal to the radiation loss. The form of the fluctuation-dissipation theorem for a restricted frequency region around a cavity mode is discussed with particular attention to the cavity mode degeneracy.

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The bonding electron distribution in silicon is determined from X-ray data. The numerical analysis is based on the Pendellösung data by Aldred and Hart (Proc. Roy. Soc. London A332 (1973) 223) for the ‘conventional’ reflections and by Fehlmann and Fujimoto (J. Phys. Soc. Jpn. 38 (1975) 208) for the ‘forbidden’ (222) reflection. It is shown that an accurate (222) structure amplitude aids greatly in interpreting the ‘conventional’ reflections in terms of Dawson’s general structure amplitude formalism. The bonding features can be described by two non-spherical scattering components plus a scalar deformation term (in the form of a radially contracted valence shell scattering amplitude). While the broad electron density features can be accurately determined, caution should be exercised in accepting the least-squares refined values for the Debye-Waller factor and for the anomalous dispersion (due to the high correlation between these parameters).

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The Debye-Waller factor of cubic CsPbBr₃ was investigated by neutron diffraction technique at 152°C. The perovskite structure model with anisotropic thermal vibrations can explain the characteristics of the thermal behavior of this substance, which turned out to be essentially the same as that of CsPbCl₃; that is, anomalously large thermal parameters for the cesium and halogen atoms are obtained.

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The angular distributions of K-shell Auger electrons from carbon, nitrogen, oxygen and neon excited by protons and alpha particles at MeV energy region have been measured. In comparison with the theoretical distribution of \bara+\barb cos² θ, the results are isotropic within the experimental accuracy of 8%. For the angular distributions of K Auger electrons from nitrogen and oxygen induced by N+N²⁺ and O+N²⁺ collisions, no significant anisotropy has been observed.

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The interference among single electronic scatterings affects the excitation. The contribution to the cross-section can be evaluated by expanding the Glauber profile function in terms of the multiplicity order. A tentative termination of the expansion up to the second order, i.e. to the double scattering term, yields further reductions of the cross-section compared with those evaluated on the basis of the Hartree-type core potential model and of the single scattering model, when the energy of the incident electron is lower than ∼200 eV. In the higher energy region, where higher order terms of the expansion less contribute to the excitation, also the model of the core potential is feasible, and as applicable to the water molecule as to alkali atoms.

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Resonance Raman (RR) Spectra of rhodopsin and isorhodopsin are theoretically analyzed and compared with those of free protonated retinylidene Schiff bases (PRSB). We used the multibond twisted chromophore conformations of rhodopsin and isorhodopsin which were previously obtained through the optical spectral analysis. The calculated frequencies and relative intensities of RR spectra of rhodopsin and isorhodopsin are almost similar to those for the corresponding free PRSB’s. Furthermore the correlation between the frequencies ν’s of normal modes and the maximum wavelength of the absorption λ is analyzed for the following three cases; a) torsion around a double bond, b) a counter-anion near N atom and c) an anion near C5 atom. As a result, the experimental fact that ν’s of C=C stretchings decrease considerably as λ increases and those of C–C stretchings increase is best reproduced in case a). The frequency of C=N⁺H stretching shows drastic decrease in case b), but moderate decrease in cases a) and c) with increase of λ.

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The perturbed stationary state (PSS) method is applied to the resonant charge transfer processes involving highly excited hydrogen atoms at low energies. The momentum transfer effect of the electron is included. It plays an important role in the energy dependence of the cross sections. The energy dependence of the calculated cross sections agree with that of the experimental results but the magnitude is about five times smaller than the experimental value.

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It is shown that ions in a low-density plasma has an excited-state population density described by corona equilibrium or by the capture-cascade scheme; for hydrogen-like ions both have the same p-dependence (p is the principal quantum number) of n(p)⁄g(p)∝p^−0.5 (n(p)⁄g(p) is the population density per unit statistical weight) for an optically thin high-temperature plasma. For an equilibrium condition, relative contribution is about 10:1, verifying the corona model commonly assumed. For a low-temperature equilibrium plasma, however, the capture-cascade component dominates over the corona one for high-lying levels. In the high-density limit partial LTE holds only if the plasma is in ionization equilibrium or in complete LTE. In view of the fact that the equilibrium plasma is a rather exceptional case in actual situations, the theory is generalized: a plasma is decomposed into purely-ionizing- and purely-recombining-plasma components.

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A calculation of the quasi-steady-state solution for a purely-ionizing hydrogen plasma shows that each excited level goes through three phases with an increase in electron density, n_e: i.e., the corona phase for low n_e, the quasi-saturation phase for intermediate n_e and the complete-saturation phase for high n_e. In the latter two phases the ladder-like excitation mechanism gives the population density distribution n(p)⁄g(p)∝p⁻⁶ (n(p)⁄g(p) is the population density per unit statistical weight of the level with the principal quantum number p). For this class of plasma Griem’s LTE criterion gives the boundaries between these phases instead of LTE. In the ionization mechanism the ladder-like excitation-ionization process becomes important when the low-lying excited levels enter into the saturation phase, and its contribution amounts to 50% of the total ionization rate for high n_e. An experiment supports these conclusions.

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With the use of the Flory-Krigbaum interaction potential between the polymer solutes, virial coefficients are calculated up to the fifth order. Both the fourth and fifth virial coefficients can take not only positive values but also negative ones. The osmotic pressure obtained from these virial coefficients is compared with experimental data. In low concentration, calculated results agree with the experimental data quantitatively. The limit of concentration up to which the results agree with the experimental data becomes clear by the calculation of the fourth and fifth virial coefficients.

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A new eigenmode analysis is presented for an inhomogeneous Vlasov plasma based on an integral equation in the wavenumber space. The effects of finite Larmor radius can be taken into account even for the case of kρ_i\gtrsim1 where k is a measure of the wavenumber in the direction of spatial inhomogeneity and ρ_i is the ion Larmor radius. The eigenfrequency is determined from a compact “quantization condition” which is an extension of the Bohr-Sommerfeld “quantization condition” for second order differential equations.

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Anomalous resistivity caused by ion acoustic turbulence is observed in a current-carrying discharge-tube plasma. Above 0.05 V/cm, which is nearly equal to a critical field predicted from an electron collision frequency, the resistivity increases in proportion to the electric field. When a magnetic field is applied to the plasma in the presence of the ion acoustic turbulence, the electron temperature rises. It is found that the electron heating is brought about by the turbulent heating.

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Experiments are conducted to study the effects of X-ray radiation and suprathermal electrons produced by laser-produced plasma on the energy transport. Plasmas were produced by irradiating aluminum coated silicon targets (layered targets) with 1.06 μm Nd: glass Baser of 10¹⁴ W/cm² power density. The nano-second time resolved X-ray spectra (1.5∼2.2 keV) were measured with the scintillator-photomultiplier array. The layer from which He-like ions are originated is limited to have a depth of 0.1 μm into the target, and the Si K_α line emitting region has a depth of about 1 μm. The duration of K_α line signal is longer than that of Al XII line (1s2p ¹P–1s^{2 1}S) signal. The K_α emission can be explained by X-ray absorption in the target material.

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Statistical analysis is made of effects of homogeneous turbulence upon magnetic field, in a close relation to the magnetic-dynamo problem. Using a statistical-mechanical approach developed in the study of inhomogeneous non-magnetic turbulence, a formula is found for the mean electromotive force playing an important role in dynamo theory. The so-called α-effect, in special, is expressed in a simple form under the pseudo-isotropic turbulent field whose statistical properties have an exponential time dependence.

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Experimental investigations on the stability characteristics of a natural convection plume in air above a horizontal line source of heat were performed. The results obtained experimentally confirm the predictions of the linear stability theory over an appreciably wide range of Grashof number. A slow fluctuation of a laminar plume, which is called swaying motion, was observed. Turbulent bursts in the transitional processes to turbulence were not detected but gradual and smooth breakdown of the initially regular disturbance waves were observed as the Grashof number increased.

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A general theory is presented to derive the coarse-grained equations governing the macroscopic behaviour of slow viscous flow in suspensions from the standpoint of statistical continuum mechanics. A system of equations governing the macroscopic behaviour of viscous flow in suspensions can be obtained using formal perturbation methods and coarse-graining procedures. The coarse-grained equations lead to an expression for the dependence of the effective viscosity of suspensions on the concentration of particles φ. In the dilute limit our result reduces to Einstein’s theory of dilute suspensions, and the deviation from Batchelor’s formula is not significant to the second order in φ. Even for more concentrated suspensions, the result is in good agreement with experimental data obtained by Vand.

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Angular distributions of differential cross sections and vector analyzing powers of protons exciting the ground state and the first excited state in ¹⁴N are measured at an incident energy of 21.0 MeV. Importance of the (p, d) (d, p) two-step process as well as tensor force is confirmed.

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