We have found several new conducting states of constant and quantized resistances in a superconducting Pb film in parallel magnetic fields between $H_{c2\mathrm{}}$ and $H_{c3\mathrm{}}$. These states can be explained qualitatively as due to the conduction of coherent quasiparticles in the normal lamina penetrated by the magnetic field.

An explicit evaluation is made of the fluctuation-induced diamagnetism from zeropoint fluctuations, which have been neglected in a previous calculation by Maki and Takayama. It is shown that in fact this contribution has another scaling field $\sim \frac{{\phi }_0}{l^2}$, as calculated previously by Lee and Payne and by Kurkijärvi, Ambegaokar, and Eilenberger. However, this term gives rise to an almost constant susceptibility (of the same order as Landau diamagnetism) in the field region of experimental interest [i.e., $H\sim H_{c2\mathrm{}}\mathrm{}\left(0\right)\mathrm{}$, the upper critical field at $T=0\mathrm{}$ K].

Absorptance and spectral response of the photoconductivity data indicate the absorption edge in $a-\mathrm{G}\mathrm{e}$ is near $h\nu =0.6\mathrm{}$ eV and not at 1 eV as suggested by other studies. The position of the optical threshold is obtained from in situ measurements on ultrahigh-vacuum—deposited films and is within experimental error of the thermal activation energy determined as the sum of the separation of the Fermi energy from the valence band and the high-temperature activation energy of the dc conductivity.

In-beam measurements of the nuclear quadrupole interaction of the isomeric states of ${}_{}{}^{67,69,71}{}_{}{}^{}\mathrm{Ge}$ in the polycrystalline metallic lattices Zn and Ga demonstrate that the unperturbed quadrupole interaction pattern can be observed for several microseconds with no indication of radiation-damage effects at target temperatures near the melting point. The symmetry of the interaction in Zn suggests that the Ge recoil nuclei reach substitutional lattice sites. The interaction frequencies point to enhanced electric field gradients at the Ge nucleus.

We have measured the valence-band density of states and the energies of the core levels of crystalline and amorphous GeTe with x-ray photoemission. The density of states of the amorphous form is found to be very similar to that of the crystal. The present results indicate that the atomic orbitals primarily determine the valence-band density of states and that these are disturbed little, even when the bonding changes significantly.

An intermediate state is shown to exist between the antiferromagnetic and spin-flop states of antiferromagnetic Mn${\mathrm{F}}_2$. This state consists of alternate thin-slab domains of antiferromagnetic and spin-flop material. Experimental evidence includes NMR, Faraday rotation, optical-absorption spectroscopy, and photographs of the domain structure. A molecular field model is used to calculate the field width of the domain region and the physical width of the domains. Reasonable numerical agreement is found.

By means of a finite-range distorted-wave Born-approximation program which exactly includes recoil, $\alpha$ spectroscopic factors are extracted from the (${}_{}{}^6{}_{}{}^{}\mathrm{Li},d$) and (${}_{}{}^{16}{}_{}{}^{}\mathrm{O}$, ${}_{}{}^{12}{}_{}{}^{}\mathrm{C}$) reactions on ${}_{}{}^{40}{}_{}{}^{}\mathrm{Ca}$. The production of ${}_{}{}^{12}{}_{}{}^{}\mathrm{C}_{}^{*}{}_{}{}^{}$($2^{+}$) is correctly predicted to be suppressed. The results are consistent with the assumption of an $\alpha$-particle transfer as dominant in the two reactions.

During a weak solar flare, energy spectra of He, O, and Fe from 0.2 to ∼ 30 MeV per nucleon were measured with glass and plastic detectors exposed on the Apollo 16 spacecraft. The spectra were very steep and the abundance ratios Fe/O and O/He decreased rapidly with energy, approaching solar atmospheric ratios at energies above ∼ 5 MeV per nucleon. The shapes of the rigidity spectra suggest that the ions were completely stripped while being accelerated.

We have observed $\gtrsim 4\sigma$ signals at mass 1760 MeV and width < 80 MeV in both the $K\pi$ mass and the ${Y_2}^0$-moment spectra from a sample of 5330 events of the type $K^{-}p\to K^{-}{\pi }^{+}n$ at 7.3 $\frac{\mathrm{GeV}}{c}$. Our evidence for a $K\pi \pi$ decay mode of this resonance is only of marginal statistical significance. We may be observing the same object as that reported previously by Carmony et al., although the detailed structure in our data is different.

We construct an anomaly-free U(1) $\otimes$ SU(2) gauge model of weak and electromagnetic interactions based on the three-triplet model of hadron structure. The model has a large number of interesting experimental consequences and requires a relatively low value for the mass of charged intermediate vector bosons; while the lower bound is 13 GeV, 18 GeV is the preferred value.

We have found a strong temperature dependence of the energy of the 6.2-keV $\gamma$ rays from dilute impurities of ${}_{}{}^{181}{}_{}{}^{}\mathrm{Ta}$ in transition-metal hosts. The observed temperature shifts cover a range of -32 to +8 times the expected thermal red shift, and exhibit large variations with the hosts.

The collisional absorption of laser radiation by a planar plasma was calculated using the classical physical optics of absorbing media. In most regions of interest to thermonuclear fusion, the enhanced absorption of $p$-polarized radiation by optical resonance—particularly at high temperatures and long laser wavelength—completely dominates the ordinary absorption due to inverse bremsstrahlung.

Rayleigh scattering is used to obtain the radial gas density and temperature distributions in low-current Ar arcs. A comparison with spectroscopic results indicates large deviations from local thermodynamic equilibrium. The possibilities of determining excited-state density distributions and transition probabilities by Rayleigh scattering are indicated.

We demonstrate the existence of an anomalous pinch effect if turbulent fields are generated by current instabilities. This effect is similar to the Ware effect, but the stationary electric force is replaced by the drag force resulting from asymmetry of the turbulent fields.

Temperature dependence of molecular dynamics as revealed by intermolecular and second-order Raman scattering in the condensed rare gases are reported with special emphasis on the behavior near the melting transition.

We observed the light emitted along a direction 45° from the beam axis when a Nd-glass laser (frequency ${\omega }_0$) was focused on a solid target. Quite intense lines were found with frequencies $2{\omega }_0$, $\frac{3}{2}{\omega }_0$, $\frac{1}{2}{\omega }_0$. The lines at $2{\omega }_0$ and $\frac{3}{2}{\omega }_0$ are broadened on the low-frequency side only. Their occurence and broadening may be related to parametric excitation of waves.

In certain ionospheric and laboratory parametric-decay-instability experiments, pump-dependent refraction modifies the nature of the instabilities. In the ionosphere, electrostatic waves cna be trapped in the gradients of the high-frequency pump. In the laboratory the refraction, and hence the convective nature of the instability, is determined completely by the pump. These simple examples suggest that pump-energy absorption may be enhanced by tailoring the pump profile to create a nonconvective instability.

The (100), simple-cubic, lattice-gas interface structure has been simulated by Monte Carlo methods. For the interface width $L$ we find $L=(1.05\mathrm{}\pm 0.04){(1-\frac{T}{T_c})}^{-0.69\mathrm{}}$, in the range $T\gtrsim 0.5T_c$. This is larger than the bulk correlation length $\xi$ by a factor of ∼ 3.

Direct observations of the magnetic-field distribution in thin films of Pb, Sn, and In indicate that the critical thicknesses separating intermediate-state and mixed-state behavior in these systems are accurately given by theoretical calculations and are much lower than has been believed on the basis of critical-field measurements.

Neutron irradiation of MgO produces $V^{-}$ centers (holes trapped at cation vacancies). X irradiation is reported to give $V_{\mathrm{A}1}$ centers: ${\mathrm{O}}^{-}$-[=]-${\mathrm{O}}^{2-}$-${\mathrm{Al}}^{3+}$. Both give identical ESR spectra at 77 K. At 295 K the three lines of the anisotropic $V_{\mathrm{A}1}$ spectrum only broaden, whereas $V^{-}$ lines coalesce to an isotropic line. Since quenched, x-irradiated crystals show this line, the presence of isolated vacancies and not the type of radiation governs formation of $V^{-}$ centers.