Exact solutions of the quasiparticle transport equation in the limit $T\to 0$ are used to calculate finite temperature corrections to the thermal conductivity and spin-diffusion coefficients of a normal Fermi liquid by a perturbation theory method. Application of the results to liquid ${\mathrm{He}}^3$ yields an estimate for the Landau parameter $F_1^{}{}_{}{}^a$

When a time-varying potential is placed on a grid located in a plasma, coherent bursts of charged particles having peak energies corresponding to the applied potential are emitted from the grid region. These ion bursts produce an ion-wavelike phenomenon, which is not predicted by the ordinary dispersion relation. We have observed these "pseudowaves" having wavelengths larger than the Debye radius, which suggests that in this case some cooperative electrostatic process must be present. These pseudo ion waves have been used as a tool to study plasma phenomena.

Starting from a zero-sound approach, a calculation of the spectral function of the current-current correlation, which is valid at short wavelengths and high frequencies, is given for classical liquids. The theory is used to explain results of neutron inelastic scattering in liquid argon.

The electronic contribution to the force constants of lattice vibrations in insulators is studied in a Green's-function formalism. Results of an application of the method to LiF are given where the one-electron spectrum has been treated in the tight-binding approximation.

Microwave absorption in the spin levels of the excited state of an ionic system can modulate the circularly polarized fluorescence from the state at right angles to an applied, static magnetic field. This modulation is detected in the broad, vibronic, sideband fluorescence of the ${\mathrm{Eu}}^{2+}$ ion in Ca${\mathrm{F}}_2$ for a modulation frequency of 9.5 GHz.

We have applied a new method for the determination of diffusion coefficients to hydrogen and deuterium in niobium. The activation energies for both isotopes are comparatively small and differ by about 20%, whereas $D_0$ is the same within experimental error. The activation energy for hydrogen diffusion is equal to the energy difference $\hslash {\omega }_{\mathrm{H}}=114\mathrm{}\pm 6$ meV between the ground state and the first excited state of the hydrogen atom in solution.

A new mechanism - the virtual recoil of solute ions - is investigated and shown to cause the dominant contribution to the thermopower of dilute alloys at low temperatures.

It has been found that the flow stresses of superconducting niobium and lead at 4.2°K increase in the transition between superconducting and normal states produced by an external magnetic field. The ratio of the increment to the flow stress in the superconducting state is 2.9% in lead and 0.6% in niobium. It is concluded that the conduction electrons in the normal metals are impeditive for the motion of dislocations.

The splitting of conduction electrons into Landau levels leads to quantum acoustic plasma modes because each level behaves as a separate species. The dispersion relation for these modes is derived and plotted in the long-wavelength approximation for high magnetic fields. Effects of Landau damping and electron scattering by impurities are estimated for semiconductors such as InSb.

The change in the lattice parameter of nearly perfect silicon and germanium crystals irradiated with 4.2 × ${10}^{19}$ fast neutrons/${\mathrm{cm}}^2$ at about 40°C has been measured. The results show an expansion $\frac{\Delta a}{a}$ equal to about 1 × ${10}^{-4\mathrm{}}$ in both kinds of crystals. Isochronal annealing experiments on irradiated germanium indicate at least two well-defined annealing regions centered at 150 and 400°C, coinciding with previous anomalous x-ray transmission experiments.

The physical equivalence between the Kondo-Nagaoka spin-compensated state and localized spin fluctuations in a dilute "nonmagnetic" alloy is demonstrated. The Kondo temperature is shown to be equal to $\tau _0^{}{}_{}{}^{-1\mathrm{}}$, the width of the spin fluctuations, and determines the boundary between magnetic and nonmagnetic behavior of dilute alloys.

We have extended earlier work on the Raman spectrum of quartz to both higher and lower temperatures (6-900°K), and find evidence for the assignment of features in the 130- to ${200-\mathrm{c}\mathrm{m}}^{-1\mathrm{}}$ region as second order. Anomalies in the temperature dependence and selection rules exhibited by several features are fully reconciled by an anharmonic interaction between a "soft" zone-center optical phonon and an excitation consisting of two oppositely directed zone-edge acoustic phonons.

The one-exciton, one-magnon system is treated for a suitable antiferromagnetic insulator, Mn${\mathrm{F}}_2$. Zone-edge excitons and magnons are found to interact quite strongly. Bound states are found to exist under favorable circumstances. The line shapes of magnon sidebands of excitonic transitions are modified. Expressions are given for the exciton-magnon coupling constants in terms of the parameters describing interionic exchange.

The absorption of Mn${\mathrm{F}}_2$ in the 4000-Å region has been examined. Evidence is presented for the assignment of a sharp line at the edge of a magnon sideband to a magnon-exciton bound state.

A method of solution by iteration is given in the number-conserving treatment of the pairing interaction. It is local in the sense that only nuclei with $A$, $A-1\mathrm{}$, and $A-2\mathrm{}$ nucleons are involved in the calculations.

Differential cross sections for the excitation of the 0.570-, 0.894-, 1.633-, 2.33-, and 2.74-MeV states in ${\mathrm{Pb}}^{207}$ have been measured in inelastic proton scattering at 20.2 MeV. Analysis via the microscopic model indicates that core polarization is important in describing these presumed single-particle transitions.

The proton-proton bremsstrahlung cross section was measured with an incident energy of 3.2 MeV at an angle of 30° in the coplanar symmetric geometry. The result for the cross section, $\frac{d^2\sigma }{d{\Omega }_{1}d{\Omega }_2}$ is ${0.15}_{-0.15\mathrm{}}^{+0.17\mathrm{}}$ μb/${\mathrm{sr}}^2$, and is compared with theory.

We have determined the multipolarity of the short-lived isomeric transition in ${\mathrm{Ta}}^{182}$ to be $M2\mathrm{}$; we have measured the half-life and transition energy; we have observed population of the state from 16-min ${\mathrm{Ta}}^{182m}$; and we make putative spin and parity assignments. Determination of the multipolarity was by a new method which should have applicability to other cases of low-energy highly converted transitions in nuclides with $Z>\mathrm{}60\mathrm{}$.

Simultaneous spectral observations of low-energy solar particles in interplanetary space and in the magnetosphere on the equator strongly imply that these particles have essentially free access to the outer magnetosphere through a very effective diffusion mechanism which preserves the spectral shapes and the flux magnitudes. These observations further imply that measurements of solar-particle arrival time over the polar caps are not sufficient to distinguish between open or closed magnetosphere models.

We measured the ${\pi }^0$ photoproduction differential cross section at 180° for a range of incident photon energies between 650 and 1750 MeV. The cross sections are dominated by the $D_{13}\mathrm{}\left(1525\right)\mathrm{}$, $D_{15}\mathrm{}\left(1688\right)\mathrm{}$, and $F_{37}\mathrm{}\left(1920\right)\mathrm{}$ resonances.