We show that nonlinear excitation of surface-polariton waves by optical mixing should be possible. The excited surface waves can be easily detected by either the prism-coupling method or coherent scattering from wave mixing. Practical numerical examples are given.

A phenomenological model for decays of $\psi$ and ${\psi }^{\prime }$ into normal hadronic modes is proposed. This model can explain the decay rate $\Gamma (\psi \to \pi \rho )$ as well as the puzzlingly large rate $\Gamma (\psi \to \varphi {\pi }^{+}{\pi }^{-})$ in comparison to $\Gamma (\psi \to \omega {\pi }^{+}{\pi }^{-})$. It also predicts many other relations which can be easily tested experimentally.

Relativistic kinematics of monopole production and propagation in Earth's atmosphere and magnetic field have been examined in the light of the observation of a magnetic monopole by Price et al. It has been shown that the observed monopole cannot result from nuclear interactions in the atmosphere and that the extraterrestrial origin of this monopole is very unlikely.

We present results from the Fermilab 15-ft bubble chamber on the charged-particle multiplicity distributions produced in high-energy charged-current neutrino-proton interactions. Comparisons are made to $\gamma p$, $\mathrm{ep}$, $\mu p$, and inclusive $\mathrm{pp}$ scattering. The mean hadronic multiplicity $〈n_c〉$ appears to depend only on the mass of the excited hadronic state, independent of the mode of excitation. A fit to the neutrino data gives $〈n_c〉=(1.09\mathrm{}\pm 0.38)+(1.09\pm 0.03)\ln W^2$.

Data are presented on charged-current inclusive strange-particle production in 10-200-GeV/c $\nu p$ interactions. Final states with $V^0$ decay topologies are reported: ${K_s}^0$, ${\Lambda }^0\left({\Sigma }^0\right)$, ${\overline{\Lambda }}^0\left({\overline{\Sigma }}^0\right)$. Neutrino energy, charged multiplicity, $Q^2$, $W$, $x$, and $y$ distributions are shown. The corrected relative $V^0$ production rate is 0.16±0.03 per event. The first example of neutrino-induced antibaryon ($\overline{\Lambda }$) production is observed. The 90%-confidence upper limit on $\Delta S=-\Delta Q$ inclusive $\Lambda$ production is 0.036 of all charged-current $\nu p$ interactions above 10 GeV/c.

Elastic electron-scattering cross sections from ${}_{}{}^{208}{}_{}{}^{}\mathrm{Pb}$ have been measured for $0.5 {\mathrm{fm}}^{-1\mathrm{}}<q<\mathrm{}2.24\mathrm{} {\mathrm{fm}}^{-1\mathrm{}}$. The charge distribution for this nucleus is determined by a "model-independent" method; it exhibits a bump in the center of the nucleus which is also a characteristic feature of Hartree-Fock calculations. The influence of the $3s$ protons on $\rho \mathrm{}\left(r\right)\mathrm{}$ has been investigated by a difference measurement between lead and thallium isotones.

Multistep core-exchange analysis has been performed for the scattering of ${}_{}{}^{16}{}_{}{}^{}\mathrm{O}$ + ${}_{}{}^{18}{}_{}{}^{}\mathrm{O}$ at four different incident energies. It has been found that the recoil effects are very important for reproducing the energy dependence of the observed cross sections. The multistep effects due to the core-exchange process are very small.

Yields of 131 nuclides were measured radiochemically to delineate the mass distribution in the reaction of 1150-MeV ${}_{}{}^{136}{}_{}{}^{}\mathrm{Xe}$ with a thick ${}_{}{}^{238}{}_{}{}^{}\mathrm{U}$ target. Six components attributed to either the quasifission or the quasielastic-transfer mechanisms were observed in the mass distribution. An upper limit of 20 mb is given for the fusion-fission process. Neutron-deficient product masses in the region $180<~A<~210$, colloquially referred to as the "gold finger," are explained as heavy quasifission products.

Relativistic Hartree-Fock calculations indicate that the dipole oscillator strengths for the $2s\to 2p_{\frac{3}{2}}$ and $2s\to 3p_{\frac{3}{2}}$ transitions of the Li sequence and those for the $2s^2{}_{}{}^1{}_{}{}^{}S\to 2s2p_{\frac{3}{2}}{P}_1$ transitions of the Be sequence deviate appreciably for $Z>\mathrm{}40\mathrm{}$ from values extrapolated from low-$Z$ ions.

In a small-scale tokamak, magnetohydrodynamic instabilities of small wave numbers, including the $m=1\mathrm{}$ mode with positive voltage spikes, were observed. They were identified as kink modes and resistive tearing modes, by a direct measurement of the plasma current profile. Relations between the fluctuations and the current profile show a qualitative agreement with the theory of kink and resistive tearing modes.

The two-dimensional plasmon dispersion relation ${{\omega }_p}^2=2\mathrm{}\pi N{e}^2\frac{k}{m}$ has been verified in the classical one-component plasma formed by a sheet of electrons in image-potential-induced surface states on liquid helium. For temperatures below 0.68 K the plasmon damping indicates that the electron mobility is limited by electron-ripplon scattering.

The presence of trivalent Sm has been observed near the (100) surface of pure semiconducting SmS using electron-energy-loss spectroscopy with 100-eV electrons. This surface phase transition is interpreted as due to differential contraction of the surface cation lattice constant for NaCl-type (100) surfaces and helps to resolve reported differences in ultraviolet and x-ray photoemission experiments on SmS.

The chemisorption of O on the (100) surface of Al is studied within the Hartree-Fock-Slater self-consistent field model using a multiple-scattering method. Good agreement is obtained with the spectral results of the jellium calculation of Lang and Williams when the O-metal distance approaches their equilibrium separation. For adsorption at a hole site, we argue that the $\mathrm{O}\mathrm{}\left(2p\right)\mathrm{}$ resonance should be deeper in the band and broader than suggested by the jellium model.

Photoionization properties for an impurity in a semiconductor are used to reconstruct the radial dependence of the bound-state wave function, through inversion of a Hankel transform. For a heuristic wave function, with effective mass approximated by a scalar, optical data for boron in Si transform to $\psi \left(\mathcal{r}\right)$ characteristic of a nonhydrogenic shallow acceptor. Data for "deeper" acceptors in Si, Ge, and GaAs dictate a compact, sharply defined charged and an effective potential steeper than Coulombic.

Using the energy and angle-of-incidence dependence of the electron-energy-loss spectra of MgO, we have separated the excitonic transitions from the Mg core levels to the excited states into those of bulk and surface origin. The bulk transitions are very nearly those of the free ${\mathrm{Mg}}^{2+}$ ion. The surface-state transitions can be described by Stark splitting of the energy levels of the surface ${\mathrm{Mg}}^{2+}$ ions in the intense Madelung electric fields at the crystal surface.

Polarized ${\mu }^{+}$ particles were stopped in spin-glass alloys CuMn and AuFe. A sharp onset of the relaxation of the muon's polarization was observed in the vicinity of the transition temperature and is interpreted as arising from the dipolar fields of frozen impurity moments. Increased temperature width of the transition in an applied magnetic field is observed as a broadening of the internal-field distribution, extending through the transition.

$1T-{\mathrm{Fe}}_x{\mathrm{Ta}}_{1-x}{\mathrm{S}}_2$ shows unusual behavior in the temperature dependence of the magnetic susceptibility and ${}_{}{}^{57}{}_{}{}^{}\mathrm{Fe}$ Mössbauer isomer shift, as a result of a low spin (${}_{}{}^1{}_{}{}^{}A_{1\mathrm{g}}^{}{}_{}{}^{}$) to high spin (${}_{}{}^5{}_{}{}^{}T_{2\mathrm{g}}^{}{}_{}{}^{}$) transition of ${\mathrm{Fe}}^{2+}$. The fluctuation rate ${}_{}{}^1{}_{}{}^{}A_{1\mathrm{g}}^{}{}_{}{}^{}\leftrightarrow {}_{}{}^5{}_{}{}^{}T_{2\mathrm{g}}^{}{}_{}{}^{}$ is faster than ${10}^7$ ${\sec }^{-1\mathrm{}}$.

In the Van Vleck compound $\left({\mathrm{Pr}}_x{\mathrm{La}}_{1-x}\right){\mathrm{Sn}}_3$, we have attained the saturation of nuclear magnetization. The observed saturation value decreases with increasing applied magnetic field. A simple model of "nuclear field" accounts well for this effect. The nuclear moment is enhanced by an electronic contribution equal to the field derivative of the electronic magnetization times the nuclear field.

Deuterium spin decoupling by double-quantum transitions in the manner of Meiboom and co-workers is applied for the first time to solids, opening the way for a new approach to high-resolution proton NMR. With use of this approach, the first resolved proton NMR spectrum of polycrystalline ice is presented and the chemical shielding tensor elements are determined. A simple treatment of the double-quantum process shows why decoupling is possible even though the deuterium spectral width is ∼200 kHz as a result of quadrupolar broadening.

Percolation thresholds in two to six dimensions are studied by Monte Carlo methods in order to test Toulouse's recent conjecture that at six dimensions the Bethe lattice description of the threshold becomes exact. The results verify the existence of this critical dimensionality, but are only qualitatively in agreement with the predictions of expansions to $6-\epsilon$ dimensions.