Whistler waves are launched from an electric dipole of length $L$ in a large-volume laboratory plasma. With increasing wave amplitude the radiation pattern narrows and finally forms a duct of diameter $d\simeq L\simeq {\lambda }_{\parallel }$. The ducted waves propagate nearly undamped. The observed nonlinear effects are explained by wave-particle interactions.

We describe an apparatus for producing a magnetized column of nonneutral electron plasma which is many Debye lengths in radius. The plasma exhibits the linear and nonlinear electron-wave effects observed in neutralized plasmas.

The liquid-to-gas transition at zero temperature in quantum systems obeying both Bose and Fermi statistics is studied. In contrast to well-known systems, the nature of this transition in these quantum systems depends on the statistics in a fundamental way. For Bose systems there is no coexistence region. For Fermi systems there is a range of masses for which there is a coexistence region and a critical mass below which this region disappears.

A new method is presented for measuring thermal or structural disorder. The additional disorder in the first Ge-O and Ge-Ge distances in amorphous Ge${\mathrm{O}}_2$ was measured by comparison with crystalline ($\alpha$-quartz) Ge${\mathrm{O}}_2$, and showed no additional disorder in the Ge-O distances but deviations in the Ge-Ge distance consistent with a ±6.5° variation about a Ge-O-Ge bond angle of 130°. These results rule out the proposed microcrystalline models.

We report piezoelectric surface excitation of coherent acoustic 0.891- and 2.53-THz phonon pulses in quartz by means of chopped infrared laser radiation and the detection of these highly collimated phonons 10 mm from the excitation area using a superconducting tin bolometer. At 2.53 THz the effect of dispersion is clearly visible. Absorption of infrared photons in the bulk material generates incoherent phonons which also can be detected by the bolometers.

Ultraviolet photoelectron spectroscopy, Auger, and thermal desorption have been combined to monitor ${\mathrm{H}}_2$O formation on platinum. The reaction probability when oxygen adsorbed on Pt is exposed to ${\mathrm{H}}_2$ was found to be strikingly high—approximately 0.7 oxygen atom removed per incident hydrogen molecule. A reaction mechanism consistent with the data is proposed.

Polarized-neutron diffraction studies are reported on a series of dilute Cu(Fe) alloys in which the $3d$-electron magnetization induced by an applied magnetic field is sensed in the (111) Bragg reflection. Utilizing the concentration dependence, the isolated-Fe-center magnetization is found to be considerably larger than the total magnetization at temperatures below 10 K. The observations lend support to the development of a Kondo spin-compensated singlet state at low temperature.

The influence of the electron-electron interaction on the energy of electrons in the lowest and first-excited sub-bands of an inversion layer has been evaluated. When these corrections are included very good agreement with experimental results is obtained. A bound inter-sub-band exciton is predicted.

We have determined the cosmic-ray ${}_{}{}^{15}{}_{}{}^{}\mathrm{N}$/(${}_{}{}^{14}{}_{}{}^{}\mathrm{N}$ + ${}_{}{}^{15}{}_{}{}^{}\mathrm{N}$) ratio with a detector sensitive to velocities of particles in the penumbra of Earth's magnetic field. Our instrument was flown twice on high-altitude balloons from Palestine, Texas, obtaining an exposure factor of 20 ${\mathrm{m}}^2$ sr h. We measure the fraction of ${}_{}{}^{15}{}_{}{}^{}\mathrm{N}$ to be 0.45 ± 0.07 at 1.5 GeV/amu consistent with an origin for nitrogen primarily due to spallation in the interstellar medium.

Conditions are given for the renormalization-group transformations of the Hamiltonian of a thermodynamic system which lead to a discontinuity in an order parameter.

We have made a high-sensitivity search with two calibrated detectors in coincidence for bursts of gravitational radiation at 710 Hz of duration < 0.1 sec. We find less than one event per day at a flux of 2 × ${10}^7$ ergs ${\mathrm{cm}}^{-2\mathrm{}}$ ${\mathrm{Hz}}^{-1\mathrm{}}$.

The $s$ and $t$ dependence of incoherent $\psi \mathrm{}\left(3100\right)\mathrm{}$ photoproduction from deuterium has been measured at the Stanford Linear Accelerator Center. $\psi \mathrm{}\left(3700\right)\mathrm{}$ photoproduction and $\psi \mathrm{}\left(3100\right)\mathrm{}$ photoproduction from hydrogen have also been measured.

A very heavy particle passed through a balloon-borne stack of Cherenkov film, emulsion, and Lexan sheets. In 33 Lexan sheets it produced tracks expected of either a nucleus with $125\lesssim Z\lesssim 137$ and $\beta \lesssim 0.92$ or a magnetic monopole with $g=137e$. Its track structure in emulsion indicated it was moving downward with $\beta ={0.5}_{-0.05\mathrm{}}^{+0.1\mathrm{}}$ and was either a nucleus with $Z\approx 80$ or a monopole with $g=137e$. These facts strongly favor identification of the particle as a magnetic monopole of strength $g=137e$ and mass $>200\mathrm{}{m}_p$.

Renormalizable field theories are found to predict a surprisingly specific pattern of scaling violation in deep inelastic scattering. Comparison with experiments is discussed. The feasibility of distinguishing asymptotically free field theories from conventional field theories is evaluated.

Structure of variable widths from about 0.3 to 1.5 MeV has been observed in analyzing-power excitation functions for inelastic proton scattering from ${}_{}{}^{26}{}_{}{}^{}\mathrm{Mg}$ and ${}_{}{}^{27}{}_{}{}^{}\mathrm{Al}$. Statistical tests and significant cross correlations show that it is very unlikely that this structure is the chance effect of random fluctuations. Thus these data are evidence for intermediate structure.

The $g$ factor of the $6_1^{+}$ state at 3189 keV ($T_{\frac{1}{2}}=5.4\mathrm{}$ nsec) in ${}_{}{}^{42}{}_{}{}^{}\mathrm{Ca}$ has been remeasured with a significant improvement in accuracy by a pulsed-beam time-differential method using an in-beam superconducting magnet at 61 kG. The $g$ factor obtained is $g\left({6_1}^{+}\right)=-0.415\mathrm{}\pm 0.015$. A $g\left(\nu f_{\frac{7}{2}}\right)=-0.53\mathrm{}\pm 0.02$ is extracted from this result by use of the coexistence wave function due to Erikson; this value is in agreement with the single-particle value of -0.547 indicating a negligible orbital anomaly $\delta g_l$.

Variable-energy photons defined to 100 keV were used to study ${}_{}{}^{238}{}_{}{}^{}\mathrm{U}$ and ${}_{}{}^{232}{}_{}{}^{}\mathrm{Th}$ from 5 to 8 MeV. The inferred fission transmission indicates (a) that the lowest $1^{-}$ fission barrier is about 6.5 MeV in ${}_{}{}^{238}{}_{}{}^{}\mathrm{U}$ and 6.3 MeV in ${}_{}{}^{232}{}_{}{}^{}\mathrm{Th}$, and (b) that there is an energy gap before the rapid opening of additional fission channels above 7 MeV in ${}_{}{}^{238}{}_{}{}^{}\mathrm{U}$.

The Hartree-Fock-Bogoliubov cranking equations are solved for ${}_{}{}^{168}{}_{}{}^{}\mathrm{Yb}$ and ${}_{}{}^{170}{}_{}{}^{}\mathrm{Yb}$ with an effective interaction obtained from the Reid soft-core nucleon-nucleon potential. Coriolis antipairing in ${}_{}{}^{168}{}_{}{}^{}\mathrm{Yb}$ and pair realignment in ${}_{}{}^{170}{}_{}{}^{}\mathrm{Yb}$ explain their anomalous high-spin spectra.

A study of the elastic scattering for the ${}_{}{}^{40}{}_{}{}^{}\mathrm{Ca}$ + ${}_{}{}^{40}{}_{}{}^{}\mathrm{Ca}$ system has been performed in the 110-150- and 170-200-MeV laboratory energy ranges. Structureless excitation functions and smooth angular distributions, rapidly decreasing with angle, suggest a strongly absorptive process, unexpected from angular-momentum-matching considerations.

The lethargic response of the lasing medium produced by the combined effects of finite bandwidth and rapid decay of the population inversion leads to a reduction of the linear gain expected in certain x-ray laser amplifiers. However, the effects of coherence brightening are also important, and in the superradiant regime, the laser output approaches that predicted by the usual calculation.