N-soliton solutions of the coupled Higgs field equation are obtained by Hirota bilinear method.

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The cyclotron waves of higher order (|n|≥2) are observed in a spiral electron beam-plasma system, in addition to the space charge (n=0) and the fundamental cyclotron (|n|=1) waves. In the frequency range of ω<nω_c, the observed waves are identified to the backward cyclotron waves, by using Fourier and inverse Fourier transformation methods.

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The new generation mechanism of the auroral kilometric radiation (AKR) is proposed. The induced bremsstrahlung interaction between the auroral electrons and the moving double layers is effective for the generation of the auroral kilometric radiation. The theory predicts the close correlation between the moving double layers and AKR. The model explains the fine structure of the AKR which is interpreted as the motion of the source region (double layers) down and up the magnetic field line at velocity about 10 km/sec.

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Mode instability is shown to occur in two models of NaCl structure as the applied pressure increases. One is Kellermann’s model which neglects the field polarizability of the ions. In the other, this factor is taken into account along with distortion polarizability. In both of them, the transverse acoustic mode in the symmetric [100] direction becomes unstable; in the former, at the Γ point and in the latter, at the X point. With further increase of pressure, the longitudinal acoustic [100] mode becomes unstable at the X point in both cases.

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The superheating of normal liquid ⁴He was investigated by means of continuous heating of liquid specimen in a small glass capillary over a temperature range 2.26 K to 4.88 K. The maximum superheating data obtained were compared with the prediction from the homogeneous nucleation theory and the data for various liquids in terms of the reduced coordinates. It is confirmed that the agreement between the homogeneous nucleation theory and experiment on ⁴He is satisfactory, and the scaled superheating depends parametrically on the quantum parameter Λ^*, i.e., the deviations of the data for quantum liquids from the classical behavior become pronounced as the parameter is increased.

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The temperature dependence of the electrical resistance of thin granular aluminum films shows the maximum far above the superconducting transition temperature due to both effects of thermodynamic fluctuations and electron localization, for the film with large normal-state sheet resistance R^N. The temperature dependence of the upper critical field or the film with (Remark: Graphics omitted.) shows the upward curvature. The results on the upper critical field are explained by a current theory of dirty superconductors including electron localization and electron-electron interactions.

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The magnetic susceptibility, electrical resistivity and nuclear magnetic resonance measurements strongly suggest that the itinerant-electron antiferromagnetism and superconductivity coexist in non-annealed (strained) bcc CrRe alloys with Re concentration of more than 17%. The Néel temperature is ∼160 K and the superconducting transition temperature is typically ∼3 K.

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The effect of perturbations (constant bias current and Ohmic resistivity) on the motion of two fluxons with identical polarity are investigated by calculating the time evolution of soliton parameters which appear in the two-fluxon solution of unperturbed sine-Gordon equation. It is demonstrated that repulsive force significantly affects the short time behavior of the soliton parameters, and gives rise to a characteristic overshoot structure in this time region. It is also shown that the long time behavior of soliton parameters is dominated by the external perturbations and relative velocity of two fluxon peaks tends to zero in this limit.

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In the study of turbulent flows by a pulsed NMR method, the signal intensity of the second spin echo in a Carr-Purcell-Meiboom-Gill sequence is measured as a function of the magnetic field gradient. A theoretical expression for the signal intensity has been obtained which seems to explain the experimental data, particularly the dependence of the signal intensity on the magnetic field gradient, more satisfactorily than the previous models.

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X-ray scattering experiments of Li₂Ge₇O₁₅ were carried out above and below the ferroelectric phase transition temperature T_c=283.5 K. The space groups are confirmed to be D_2h¹⁴-Pbcn and C_2v⁵-Pbc2₁ above and below T_c, respectively. The coupling between the ferroelectric displacements of atoms along the c-direction and the displacements of atoms along the a-direction is important to cause the phase transition.

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Similarity solutions of the modified Kadomtsev-Petviashvili equation are investigated by using infinitesimal transformations of Lie’s method. It is shown that the modified Kadomtsev-Petviashvili equation can be transformed, by the first reduction, to modified Boussinesq-type, the modified K-dV equations and others.

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In the local jet space, constructed a pair of operators commuting on a given arbitrary manifold. The algorithm is applied to the nonlinear evolution equation of the polynominal type to obtain Lax pair and the condition necessary and sufficient for the existence of the pair is given in the formal theory.

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Radiative proton capture reactions through two isobaric analogue resonances (IAR) in ⁸⁹Y were studied, one was the 12.07 MeV 2d_5⁄2 state lying just above the neutron threshold energy B_n and another was the 14.48 MeV 2d_3⁄2 state lying well above B_n. E1 transitions from these IAR’s were studied for favoured cases with no spin-flip and no change of radial nodes, and for unfavoured cases spin-flip and/or change of radial nodes. At the 2d_3⁄2 IAR lying well above B_n, the favoured transitions show the resonance feature, but the unfavoured ones not. At the 2d_5⁄2 IAR near B_n, however, both the favoured and unfavoured transitions show the resonance feature. Anormalous resonant feature of the unfavoured transitions is interpreted mainly due to the compound process. Favoured transitions are all found to be reduced by factors ∼0.3 over the shell model values.

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The spin-orbit splittings are calculated for the proton single-particle resonances in ⁹¹Nb, ¹²¹Sb and ²⁰⁹Bi nuclei. Many sets of spin-orbit partners with narrow widths are obtained in these nuclei. It is suggested that the proton single-particle resonances provide a useful tool of studying the origin of the spin-orbit coupling.

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The K-capture probabilities in the decay of ¹³³Ba to 437, 383, 161 and 81 keV levels have been determined from the analysis of the K X-ray-gamma ray sum peaks observed with an intrinsic Ge detector. The measurements on 161 and 81keV levels are reported for the first time in literature.

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The method of Synchronized Quantum Beat Spectroscopy has been improved by introducing the amplitude modulation on the excitation pulse train. By using an amplitude-modulated train of picosecond pulses from a cw mode-locked dye laser, we obtain resonance enhancement of the substate coherence (quantum beat) at f₀=nf_p+n′f_m (n, n′: integer, f₀: sublevel splitting, f_p: pulse repetition frequency, f_m: modulation frequency), which can be detected by monitoring the optical anisotropy due to the substate coherence. Resonances can be obtained in the frequency domain by sweeping f_m. Pressure shift coefficients of the hyperfine splitting in Na 3²S_1⁄2 are measured to be 82, 61, −1 and −47 Hz/Torr for He, N₂, Ar and Kr, respectively, within an accuracy of ±3 Hz/Torr.

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ATR technique (glass prism-index matching oil-Ag-CaF₂ single crystal) has been used to observe long-range surface plasmon polaritons discussed recently by Sarid. At 632.8 nm, we have successfully observed the surface plasmon polaritons in the propagation distance of 105 μm.

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Two-dimensional slow viscous flow around an inclined fence on an infinite plane is investigated on the basis of the Stokes approximation. A formal expression for the flow is obtained by solving a pair of simultaneous Wiener-Hopf equations. Force and moment exerted on the fence are calculated and features of the flow are discussed.

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Linear stability theory is applied to the problem of the stability of natural convection which occurs in a vertical fluid layer with uniformly distributed internal heat sources. The two parallel bounding plates are assumed to be maintained at constant and equal temperature. The power series method is adopted to obtain essentially exact values of the critical Reynolds number R_c, the critical wavenumber α_c and the crtical wave speed c_c for ten finite values of the Prandtl number P ranging from 0.01 to 1000. It is shown that the power series method is a powerful tool for linear stability problems when the values of αRM and αRPM are both less than about 8000, where M is the maximum value of |\barW−c|, \barW being the dimensionless velocity profile of the base flow.

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Relaxation process of the runaway electron energy in a plasma is studied numerically by using the quasi-linear equations combined with a Fokker-Planck collision term. It is assumed that the relaxation is caused by the interactions of the runaway electrons with the plasma waves of ω_k=ω_pek_z⁄k.
It is shown that the perpendicular energy of the runaway electrons increases rapidly with time, while that the parallel one decreases relatively slowly. Time developments of the wave spectrum and the electron distribution function are in detail examined. The relaxation process is closely correlated with the asymptotic value of the energy density of the plasma wave excited.

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The permeability of a random array of identical rigid-spheres is determined as a function of the radius, a, and the volume concentration, c, of the spheres. A statistical formulation due to Lundgren is used here. A particular state formed around a test sphere, which is called the intermediate layer, is taken into consideration by adding the radial dependence of a coefficient of a Darcy resistance. A resultant equation is solved approximately by Galerkin’s method, then the permeability is derived from the solution by using the self-consistency condition. It agrees with the experimental data near c=2⁄3. Thus, the formula for the permeability of the densely packed bed of spheres is improved.

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Radial profiles of the plasma space potential are measured in Nagoya Bumpy Torus (NBT-1) by the use of a heavy ion beam probe. Asymmetric potential profiles owing to toroidal drift are observed in high pressure operation (C-mode). As the pressure is decreased, toroidal plasma is effectively heated (T-mode), poloidal precessional frequency overcomes the electron collision frequency and the equipotential surfaces becomes concentric inside the hot electron ring.

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The crystal structure of monoclinic RbD₂PO₄ at room temperature was determined by use of an automatic four-circle X-ray diffractometer, and the superlattice structure was examined. The crystal, which undergoes the phase transitions at 44°C and 104°C, belongs to the space group P2₁ in the lowest (III) phase and P2₁/m in the highest (I) phase. The former space group is consistent with the recent result that the crystal in the phase III is approximately antiferroelectric, but weakly polar along the b axis. There are two kinds of hydrogen (deuterium)-bond chains: one along the b axis and the other along the c axis. It is suggested that the deuterium atoms in the former chains along the b axis are ordered in the phase III and disordered in the phases I and II, while those along the c axis are ordered even in the phase I. The space group of the intermediate (II) phase is suggested to be P2₁/n.

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Rotational tunneling and torsional energy states of the NH₄⁺ ion in several alkali halide lattices (KCl, KBr, KI, RbI and CsI) have been characterized in the energy range 0<ε<42 meV. The most detailed spectra are obtained for the specimen KBr/NH₄Br (0.5 mole%) at low energies (ε<2 meV) and in the temperature region 1.5<T<30 K.
The results are consistent with a model of energy states for a tetrahedron in an octahedral field.
An investigation of the ratios of the intensities of neutron energy loss and energy gain peaks in the spectra for KBr/NH₄Br (0.5%) leads to the conclusion that conversion between the nuclear spin symmetry species of NH₄⁺ occurs with a characteristic time of several hours. This is in general agreement with the findings of NMR measurements on the same specimen that are described in the following paper. Moreover, the heat capacity results display a non-lattice contribution which is much less than that which would correspond to rapid spin conversion. On the other hand, the intensity ratios for the neutron spectra of two specimens prepared by evaporation of aqueous solutions (KI/NH₄I (2.3%) and RbI/NH₄I (2.9%)) suggest that conversion is more facile in them.

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Nuclear magnetic relaxation of the protons of NH₄⁺ in dilute solution (0.5 mole%) in KBr is measured between 2 and 259 K. The approach to equilibrium at 4.2 K is slow, the time constant being 1.5±0.2 hr, owing to conversion between nuclear spin symmetry species. There is a minimum in the spin-lattice relaxation time of 3.8±0.2 s at 5.3 K. From the slope of T₁ vs T⁻¹ on the high temperature side, the activation energy is found to be 105±10 J mole⁻¹, which approximately corresponds to some average of separations between low-lying rotational levels. The spin-spin relaxation time, T₂, is also long (1.0±0.1 ms) and independent of temperature. The equilibrium value of ⟨I(I+1)⟩, the ensemble average of the resultant nuclear spin, is slightly less than 4.3 at 4.2 K. Deviations from Curie’s Law are observed below about 10 K. These results are compatible with a model of the NH₄⁺ ion as a three-dimensional quantum rotor placed in a potential field of octahedral symmetry.

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The Raman scattering and optical absorption spectra have been measured under hydrostatic pressure up to 1.67 GPa in the layer compound red-HgI₂. The Raman spectrum shows that the bending force of HgI₄ tetrahedra is too weak for a layer to vibrate rigidly in the so-called rigid-layer mode. The bending force increases rapidly with pressure, whereas the van der Waals force remains unchanged. These characteristics originate from the fact that the bond ionicity is extremely high and sensitive to pressure. The fundamental absorption edges exhibit red shifts, giving an evidence that the ionicity decreases with pressure. Anisotropy in elastic constants is also discussed in relation to the nature of chemical bondings.

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The coefficients of the linearized basic equations for thermo-elasticity and lattice vibration derived from the continuum approximation of the self-consistent Einstein model are estimated for FCC (Cu, Ag, Al, Pb, Ni) and BCC (Cr, Mo,W, Fe) crystals by assuming the Morse type pair-potentials. Two typical deformations, i.e., a uniaxial extension and a simple shear, are studied by using the linearized equations to show explicitly the effect of strain on the amplitude of the lattice vibration in a cubic crystal.

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The sound velocity of sodium was measured in the solid phase and the liquid phase near the melting point by ultrasonic pulse transmission method. The temperature range of the experiment was from 19°C to 160°C, and the frequency of sound used was 1 MHz. The sound velocity and its temperature coefficient in the solid phase just below the melting point (97.8°C) were 3180 m/s and −1.23 m/s·deg, respectively ; and those in the liquid phase just above the melting point were 2515 m/s and −0.52 m/s·deg, respectively. By combining the present results with the existing data of thermal expansivity and specific heat, the elastic properties of sodium at and around the melting temperature were presented and discussed.

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Effect of hydrostatic pressure was studied for the phase transitions in tetramethylammonium tetrabromometallic compounds, {N(CH₃)₄}₂XBr₄ (X: Zn, Co). The transition temperatures in the -ZnBr₄ and -CoBr₄ compounds (14.8°C and 14.0°C, respectively, at 1 atm) linearly increase with increasing pressure with the ratios of 0.184 deg MPa⁻¹ and 0.182 deg MPa⁻¹, respectively. Any intermediate phases were not observed at high pressures up to about 200 MPa.

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The theory of antiferroelectric transition in copper formate tetrahydrate based upon a dimer model (J. Phys. Soc. Jpn. 34 (1973) 888) is extended to include the contribution of anharmonicity in interaction of sublattice polarization. For the case of zero applied electric field the temperature behavior of the model system is analyzed with emphases put on the tricritical point, and the peculiarity encountered around the temperature of saturation of the order parameter is pointed out. The applied field vs temperature phase diagram is discussed.

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A study is made on an Ising spin system on a triangular (actually hexagonal) lattice which contains the couplings of the nearest neighbor (J₁) and the next-nearest neighbor (J₂<0: antiferromagnetic). A mean field approximation is employed. Infinite numbers of higher-order commensurate structures with one-dimensional modulation are shown to be stabilized at finite temperatures. Analytic calculations are performed at low temperatures to find that the model exhibits a complete devil’s staircase at J₁\gtrsim0 and ordinary staircases with infinite steps at J₁\lesssim0 and J₁\lesssim2|J₂|. It is shown that most of the phases stabilized around J₁=0 are partially disordered states. Numerical calculations are also made to construct a global phase diagram. The structure of the phase diagram is discussed in terms of domain boundary. In this context the order-disorder transition of (Nb_1−xTa_x)₂ C is compared with the theory.

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Photodoping of silver into the cleaved surface of single crystal As₂S₃ (natural orpiment) was observed by electrical resistance measurements and Rutherford backscattering spectrometry. The initial stage of the phenomenon was concluded to be photo-oxidation of silver at the interface between silver and As₂S₃, and was proved to be independent of the amorphous nature like photodarkening observed in amorphous chalcogenides.

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The field enhancement for a p-polarized incident light near a sinusoidal grating surface arising from surface-plasmon-polariton excitation is studied by an improved first-order perturbation theory in which the importance of the back-scattering terms is taken into account. The dependences of the reflectivity and the enhancement factor on the amplitude of the grating are discussed. The maximum enhancement factor and the most suitable grating amplitude are calculated as functions of the frequency of the incident light for various grating periodicities, Under certain circumstances, the field enhancement may achieve above 10³ for Ag gratings near 1.3 eV of the incident-light frequency. It means 10⁶ times enhancement of the Raman scattering (SERS) of molecules adsorbed on the metallic grating surface.

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The deep level photoionization spectrum in a simple one-dimensional model is studied within the semiclassical Franck-Condon approximation for the electron-lattice coupling. The line shape functions are obtained exactly both for the one-electron and the two-electron system and various spectral features are discussed. The spectrum of the two-electron trapped state depends on the mutual Coulomb repulsion as well as on the electron-lattice coupling, the potential depth and the temperature.

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Explicit two-polaron solution is found in the continuum model of trans-polyacetylene. The solution is explored to examine stability of two polarons. It is found that two free polarons attract each other with a long range force until they form a single polaron with two carriers therein, which then dissociates into charged kink-antikink pair owing to a short range repulsion. Thus the reaction mechanism of two polarons into two charged kinks is clarified.

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The electrical resistivity of liquid Pb–Te alloys has been measured as a function of temperature and concentration. The resistivity isotherm has a remarkable maximum and the temperature coefficient of the resistivity has large negative value around the equiatomic composition, suggesting that a kind of compound formation exists at this composition. The excess resistivities are interpreted in terms of the resonance scattering caused by the compound of PbTe with a finite life time. A similar behaviour of the resistivity in liquid Sn–Te alloys is also explained satisfactorily by the same model.

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On the assumption that the Landau subband splitting is much larger than the subband width, the dynamical diffusion coefficient D(ω, E) of a two dimensional electron system scattered by randomly distributed short-ranged impurities under strong magnetic fields is determined through diagramatic self-consistent treatment. The case where the Fermi energy E lies within the N-th Landau subband with N≠0 is considered. Essential features of D(ω, E) are the same as in the case with N=0 which was discussed in the previous work. The quantity D(0, E) is finite only when the Fermi energy E is equal to E_N (the “subband center”) at which the real part of the Green function for the N-th subband becomes zero, i.e., all the states are localized except for those at the subband center. The N-dependence of D(0, E_N) and the N- and E-dependences of the localization length for E≠E_N are discussed.

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A theory of phonon dynamics of superconductors is presented on the basis of a Hamiltonian which includes the bare Coulomb interaction term and the bare ion frequency term. A diagram method which corresponds to the random phase approximation is adopted. This theory can provide a basis for discussions of anomalies of the phonon structure. In connection with anomalous aspects of phonon dynamics there exist several works in which anomalies directly reflect the singular behavior of the proper polarization function of the density fluctuation in the superconducting case. These works are criticized through our theory.

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The ground state of the one-dimensional antiferromagnetic Heisenberg-Ising model coupled with the lattice distortion is determined based on the phase Hamiltonian defined by the boson representation of the spinless fermions. This phase Hamiltonian can describe properly the possible feature of the resonating valence bond proposed by Anderson. All the possible states, including the spin-Peierls state, the Néel state, and states with both lattice distortions and magnetic orderings, are examined within the self-consistent harmonic approximation by use of the treatment of Nakano and Fukuyama which extends the theory of spin-Peierls state of Cross and Fisher. The phase boundary for small Ising anisotropy is determined which separates the spin-Peierls state and the Néel state, and it is found that the former state is stable in a wide region of parameters.

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The field-, temperature- and angular dependences of T₁ of proton in the three metamagnetic states of Ising-like one-dimensional antiferromagnet CoCl₂·2H₂O have been studied in view of two different types of relaxation mechanisms; the two-magnon process and the relaxation process due to scattering between one-magnon excitation and two-magnon bound state. The calculations for the former process based on the small-k approximation are in good agreement with the experimental results in the antiferromagnetic state with the external fields less than about 23 kOe. The experimental results in higher fields (223 kOe) over the three metamagnetic states are reasonably interpreted by the latter process, which predicts an approximate equation T₁⁻¹∼exp (−2g_⁄⁄μ_BH_eff⁄k_BT) where H_eff is an effective field acting on effective ferromagnetic chains in each of the three states.

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As determined by ⁷⁹Br-NQR the second order transition for [(CH₃)₄N]₂ZnBr₄ occurs between the space groups Pnma and P2₁/n11 in a very broad temperature range. The enthalpy change as found from differential scanning calorimetry is in agreement with an order-disorder transition based on the mobility of tetramethyl-ammonium ions.

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The existence of the successive long-period superstructures, or the “devil’s staircase”, in the temperature evolution of the incommensurately modulated structure has been examined in Rb₂ZnBr₄ by the neutron diffraction method. Detailed measurements of the third order satellite scattering in the temperature region close to the incommensurate-to-commensurate phase transition have shown that the temperature evolution takes place in more complicated manners than previously reported for this compound. At least three different modulations with distinct wave numbers separated by finite gaps coexist and each of them changes continuously with temperature accompanying the change in the population of the domains corresponding to the respective wave numbers. Assignment of some part of the wave number vs temperature curves to the stairs with fractional numbers afforded no positive evidence of the “devil’s staircase”.

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Effect of deuteration on the phase transitions in tetramethylammonium tetrabromocuprate crystal was studied. At 1 atm. the deuterated compound {N(CD₃)₄}₂CuBr₄ shows three phase transitions at −2°C, −31°C, and −36°C on cooling, and it is ferroelectric between −31°C and −36°C. These transition temperatures almost coincide with those in the normal compound. The pressure-temperature phase diagram of the deuterated compound is also very close to that of the normal compound. Then the effect of deuteration on the phase transitions in tetramethylammonium tetrabromocuprate crystal is negligibly small making a sharp contrast with the considerable deuteration effects in ferroelectric tetramethylammonium tetrachlorozincate and -cobaltate crystals.

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The effect of hydrostatic pressure was studied for the phase transitions in the two forms of RbD₂PO₄; monoclinic (ferrielectric) and tetragonal (ferroelectric) crystals. In monoclinic crystal, the I–II and II–III transition temperatures monotonically decrease with increasing pressure, and the phase boundaries are represented by a quadric form of T_c=T_c⁰+Kp+γp² with the parameters of T_c⁰, K, and γ being 102.5°C, −50 deg GPa⁻¹, −39 deg GPa⁻² for the I–II transition and 41.8°C, −24 deg GPa⁻¹, −15 deg GPa⁻² for the II–III transition, respectively. A pressure-induced phase of IV was newly observed above about 0.7 GPa. The transition to phase IV shows marked first order character. In tetragonal RbD₂PO₄, the ferroelectric Curie temperature monotonically decreases with increasing pressure with the initial slope of −47 deg GPa⁻¹. The slope of the Curie temperature against pressure seems to decrease as pressure increases above about 0.3 GPa.

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Rayleigh and Brillouin scattering spectra of RbH₃(SeO₃)₂ have been observed around the phase transition temperature T_C. The temperature dependence of the Brillouin frequency shifts shows a small anomaly near T_C in all three principal directions. The sound-velocity dispersion is found only in the c₅₅ transverse mode. The intensity of the Rayleigh component is insensitive to temperature even just near T_C. The existence of dynamic clusters above T_C is discussed and its characteristic frequency is roughly estimated, while static clusters are concluded not to exist in the same temperature region.

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Far-infrared magneto-plasma wave transmission in Bi was observed in pulsed high magnetic fields up to 40 T using an HCN laser (337 μm wavelength). The Fabry-Pérot interferograms due to the propagation of the Alfvén wave were observed as well as the cyclotron resonance, the combined resonance, and the Shubnikov-de Haas effect. The mass densities were obtained for the magnetic field parallel to the binary axis and electric field parallel to the bisectrix and trigonal axis. The lattice dielectric constant ε_⁄⁄ was obtained as ε_⁄⁄=48. As for ε_⊥, however, an anomalously large increase of ε_⊥ was observed as the magnetic field was increased above 14 T. The large field-dependence of ε_⊥ was explained semi-quantitatively by the interband coupling between the lowest Landau levels of the conduction and valence bands for light electrons.

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The photoacoustic and the conventional optical absorption spectra of (As₂Se₃)_100−xGe_x (x=0, 1, 5, 10) glasses were observed at room temperature. The non-radiative recombination processes of these materials were analyzed based on the existence of electron-phonon coupling. We found that the non-radiative recombination processes and the photostructural change (PSC) are very well explained by an adiabatic potential and that, in total photon intensity (I₀t) dependence of PSC, the increasing of the sample temperature due to increasing the value of I₀t is very important.

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A Laue pattern is observed for the ordered array of polystyrene latex particle. The pattern is well corresponding to a fcc lattice. The time correlation of intensity of scattered light, g⁽¹⁾(τ), is also measured and analyzed. The intensity fluctuation of Laue spot shows a long time-correlation which can be approximately expressed as g⁽¹⁾(τ)∼(τ)^−0.61 at longer correlation time. The fact that decay constants, Γ, of g⁽¹⁾(τ) show maximum at the half of the scattering angle of the Laue condition indicates that the movement of particle is correlated with each other.

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A theory is presented for the resonant 3d-band photoemission spectra in Ni on the basis of a hybridized s- and d-band model. The interference effect is taken into account between the 3p-core electron excitation followed by a super Coster-Kronig decay and the direct 3d-electron excitation. The photoemission intensities and their spin polarizations both for the 6 eV satellite and Auger peaks are calculated as a function of the incident photon energy ν, and the results are in good agreement with experiments. It is shown that the interference effect is important in explaining the observed ν-dependence of the spin polarization of satellite.

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Secondary emission (SE) spectra under excitation around the indirect exciton edge of BiI₃ crystals are studied at liquid helium temperatures (LHeT). The spectra consist of one-phonon non-resonant Raman scattering lines, and two-and multi-phonon resonant Raman scattering (RRS) lines associated with hot luminescence (HL) bands due to phonon assisted exciton recombinations. Detailed results on excitation-energy and temperature dependences of the spectra are presented. The RRS cross sections are analyzed on the basis of exciton damping processes near the exciton band bottom, and the HL line shapes are discussed on quasi-thermal equilibrium distribution under the same relaxation mechanisms.

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