Coupling of orbital resonances by a quadrupole field is shown to be a mechanism consistent with the anomalous losses of electrons, both sudden and steady state, seen in an experiment by Luckhardt and Fleischmann in the RECE-Berta (relativistic-electron coil experiment) device. The effect is shown using both analytical (nonlinear Hamiltonian mechanics) and numerical (orbit code) techniques.

Chemisorbed hydrogen on a tungsten(100) surface produces major effects in two regions of the adatom density, at ${\rho }_1\simeq 3\times {10}^{14}$ and ${\rho }_2\approx 5\times {10}^{14}$ H atoms/${\mathrm{cm}}^2$. Changes at ${\rho }_2$ are probably caused by conventional adatom-adatom interactions, but the effects at ${\rho }_1$ appear to have a different origin and we propose that hydrogen produces displacement waves in the metal surface which gradually disappear above ${\rho }_1$. This type of adsorbate-induced reconstruction may also have been observed for H on Mo(100) and Cs on W(100).

A new phase in Cs${\mathrm{H}}_2$P${\mathrm{O}}_4$ is induced by pressures above about 3.3 kbar; this phase is confirmed to be antiferroelectric by the observation of $P-E$ double hysteresis loops. The qualitative change from the paraelectric-ferroelectric to the paraelectric-antiferroelectric transition caused by the pressure is interpreted to originate in the one-dimensional characteristics with the chainlike ordering of the hydrogen bound along the $b$ axis in Cs${\mathrm{H}}_2$P${\mathrm{O}}_4$.

By fully exploiting the properties of synchrotron radiation, a surface photoyield spectrum of a metal, namely aluminum, was obtained for the first time. This type of spectrum has been theoretically discussed since 1928. The extreme surface sensitivity, which is implicit in the transition matrix element for the surface photoexcitation process, was experimentally confirmed. The applied photoemission technique, therefore, provides one of the most powerful tools for the investigation of charge distribution and dielectric response at metal surfaces.

Thallium in $a$-${\mathrm{As}}_2$${\mathrm{Se}}_3$ reduces transient hole transport but has no effect upon the photoluminescence and photoinduced ESR. The results are discussed in terms of the recent models of charged defects in chalcogenides.

A study is presented of elementary excitations of an unfrustrated system which can exhibit frozen magnetism without average long-range order. In three dimensions long-wavelength excitations are quasipropagating with linear dispersion and quadratic damping in accord with hydrodynamic speculations and computer studies, but high-energy modes may be localized. In lower dimensions the modes are overdamped even in a linearized equation-of-motion approximation.

The magnetostriction of dilute alloys of rare-earth impurities in Y${\mathrm{Pd}}_3$ follows closely the simple $\frac{H}{T}$ dependence of the field-parallel component of a quadrupole moment on the free rare-earth ion moving with the magnetic moment. The saturated magnetostriction per impurity ion is as large as in the magnetically ordered state of rare-earth compounds but does not trace the Stevens factor across the rare-earth series.

An annular magnetically insulated diode in a cusplike magnetic field has been used to produce an ∼6-kA, ∼190-kV rotating proton beam. Diamagnetic signals and magnetically insulated Faraday cups indicate that (35±15)% of the beam traversed the cusp and reached the end of the system magnetic field 35 cm from the diode. Diamagnetism was in excess of 2% of the 8-kG applied field, and the beam was distinctly hollow with a 6-cm average radius.

A Bäcklund transformation for the Ernst equation arising in general relativity in connection with several physical problems is derived, using the pseudopotential method of Wahlquist and Estabrook. A prolongation structure is also constructed, using a method of writing the equations in terms of differential forms, and an equation in the spirit of Lax is constructed, somewhat different from that given by Maison. Possible uses of the Bäcklund transformation to generate new solutions are mentioned.

The $s$ and $u$ variations of the $\mathrm{np}$ charge-exchange ($\mathrm{np}\to \mathrm{pn}$) cross section are measured to be relatively smooth and without structure at intermediate energies—in sharp contast to previous results.

Measured energy-dependent rates of opposite-sign dimuons produced by neutrinos and antineutrinos are presented and used to determine the fraction of strange quarks. Experimental distributions are compared with those expected from charm production and decay.

With use of the Stanford Linear Accelerator Center hybrid facility 1-m bubble chamber fitted with tantalum plates, a measurement was made of direct unexplained $e^{+}{e}^{-}$ pair production in 18-GeV/c ${\pi }^{\pm }p$ interactions. Limits are set in ${\pi }^{+}p$ processes. In ${\pi }^{-}p$ a signal is observed which cannot be caused by $\eta$, $\omega$, or $\rho$ decay, and for masses $>m_{{\pi }^0}$, $\frac{e^{\pm }}{{\pi }^{\pm }}=(0.87\mathrm{}\pm 0.25)\times {10}^{-4\mathrm{}}$. Some properties of the events are discussed.

The construction of no-cutoff Euclidean Green's functions for nonrenormalizable interactions ${\mathcal{L}}_I\left(\varphi \right)=\lambda \int d\delta \left(\epsilon \right):\exp \epsilon \varphi :$ in four-dimensional space-time is carried out. It is shown that all axioms for the generating functional of the Euclidean Green's function are satisfied except perhaps SO(4) invariance.

The amplitude of $K_S$ regeneration by electrons, $\frac{{f_{21}}^e}{k}=-\left(\frac{\alpha }{3}\right)〈R^2〉$ ($〈R^2〉$ is the $K^0$ charge radius), can be determined by comparing the rates of coherent (transmission) regeneration and of diffraction regeneration at $q^2=0\mathrm{}$. We made a determination from 30 to 100 GeV/c, using a novel approach: Two distinct Pb regenerators, of optimized thicknesses, were exposed to a double beam, and interchanged every burst. We find $〈R^2〉=-(0.054\mathrm{}\pm 0.026)$ ${\mathrm{fm}}^2$. The sign, magnitude, and $p$ independence agree with predictions.

Differential cross sections have been measured for the reaction ${}_{}{}^{40}{}_{}{}^{}\mathrm{Ca}(n, {\gamma }_0){}_{}{}^{41}{}_{}{}^{}\mathrm{Ca}$ at seven angles in 1-MeV steps and at ${\theta }_{\mathrm{lab}}=90\mathrm{}°$ in 200-keV steps for incident neutron energies of 6-13 MeV. The extracted $a_2$ coefficients and the fore-aft asymmetry are in good agreement with a direct-semidirect model calculation if the isoscalar giant quadrupole resonance is included.

Elastic scattering of 104-MeV $\alpha$ particles from ${}_{}{}^{48,40}{}_{}{}^{}\mathrm{Ca}$ was measured between 3° and 110°. Optical-model fits were made using a Fourier-Bessel description of the real potential and also using density-dependent folding models. The average result for the difference between nuclear-matter rms radii is ${\mathcal{r}}_m\left({}_{}{}^{48}{}_{}{}^{}\mathrm{Ca}\right)-{\mathcal{r}}_m\left({}_{}{}^{40}{}_{}{}^{}\mathrm{Ca}\right)=0.12\mathrm{}\pm 0.06$ fm. Comparisons are made with results obtained by other methods.

An unambiguous and model-independent separation of direct and compound elastic cross section was performed by a simultaneous fluctuation analysis of the cross section and the analyzing power for the reaction ${}_{}{}^{30}{}_{}{}^{}\mathrm{Si}(p_{\mathrm{pol}},p_0){}_{}{}^{30}{}_{}{}^{}\mathrm{Si}$. The compound elastic cross section was calculated by means of Hauser-Feshbach theory without any adjustable parameters. Comparison of experiment with the calculation results in a compound-elastic enhancement factor of 2.09±0.14 for this strong-absorption, many-channel case.

We have observed ion formation (both ${\mathrm{Na}}^{+}$ and ${\mathrm{Na}}_2^{+}$) and radiation from high-lying Na states when low-density vapor (∼${10}^{13}$ ${\mathrm{cm}}^{-3\mathrm{}}$) is irradiated with a cw dye laser tuned to one of the $D$ lines. The ${\mathrm{Na}}^{+}$ ions probably result from photodissociation of ${\mathrm{Na}}_2^{+}$ formed by $\mathrm{Na}\mathrm{}\left(3p\right)-\mathrm{Na}\mathrm{}\left(3p\right)\mathrm{}$ associative ionization, while the high-lying radiating states are formed in energy-pooling reactions.

Molecular-photoelectron angular distributions are shown to depend qualitatively on symmetry-breaking hole localization during inner-shell photoionization. This is illustrated by comparing localized and delocalized calculations of the asymmetry parameter $\beta \left(\epsilon \right)$ for $K$-shell photoionization of ${\mathrm{N}}_2$ in the vicinity of the $f$-type shape resonance at approximately 10 eV above threshold. Comparison with the isoelectronic CO shows that the $K$-shell $\beta \left(\epsilon \right)$ for ${\mathrm{N}}_2$, in the localized treatment, resembles that for the $K$ shell of oxygen rather than carbon in CO.

We derive simple expressions for the collisional redistribution function which are not restricted by impact theory and hence encompass the cases of excitation and detection far from resonance. For an isolated resonance line, the redistribution function depends only on quantities already involved in the absorption profile. This implies simple relations between results obtained from light-scattering experiments and those obtained in emission or absorption spectroscopy.