We report NMR experiments which imply that highly one-dimensional spin diffusion occurs in undoped trans-${\left(\mathrm{CH}\right)}_x$ and trans-${\left(\mathrm{CH}{\left(\mathrm{As}{\mathrm{F}}_5\right)}_{0.1}\right)}_x$. The corresponding anisotropy in the diffusion coefficient would be about ${10}^6$.

A general result for the nonequilibrium distribution function for photons gives a greatest lower bound for the radiation flux spectrum. This inequality allows one to establish, from the recent measurements of the cosmic background radiation, that the observed spectrum arises from the superposition of single sources. Since the primeval fireball may be one of the single sources, it is inferred that the observed spectrum is consistent with a big-bang origin for the universe.

Closed-form solution for the superspace connections of extended supergravity in terms of supervielbeine are given for arbitrary values of $N$, and deSitter parameter $e$. A reduction procedure from the Riemannian geometry is used to deduce the desired solutions.

It is found that nonspectator interactions between $c$ and $d$ quarks in the ${{\Lambda }_c}^{+}$ give a substantial enhancement of its decay rate. The lifetime relation $\frac{\tau \left({{\Lambda }_c}^{+}\right)}{\tau \left(D^{+}\right)}={[1+\frac{\tau \left(D^{+}\right)}{(3\mathrm{}\times {10}^{-13\mathrm{}} \mathrm{s})}]}^{-1\mathrm{}}$ is derived, based on the assumption that the $D^{+}$ decays purely via charm quark decay. The semileptonic branching fractions are related by $B_l\left({{\Lambda }_c}^{+}\right)=B_l\left(D^{+}\right)\times \frac{\tau \left({{\Lambda }_c}^{+}\right)}{\tau \left(D^{+}\right)}$.

Total prompt muon production rate for muons with $P_{\mathrm{lab}}>8\mathrm{}$ GeV has been measured in 350-GeV $p$-Fe collisions. A prompt rate of (3.29±0.45)×${10}^{-4\mathrm{}}$ per collision is determined, yielding $\frac{\mu }{\pi }=(0.93\mathrm{}\pm 0.13)\times {10}^{-4\mathrm{}}$. The $\frac{\mu }{\pi }$ ratio does not show the rise at small $X_{\mathrm{F}}$ and small $P_T$ seen in intersecting-storage-ring $\frac{\mathrm{electron}}{\pi }$ measurements. A charm production cross section of 22±9 μb/nucleon is extracted from the contributions of prompt single muons to the total prompt rate.

Measurements of the differential cross section for pion charge exchange on ${}_{}{}^3{}_{}{}^{}\mathrm{H}$ have been carried out at incident pion momenta of 232 and 252 MeV/c. The results are compared with several theoretical predictions and also with charge-independence bounds determined from elastic-scattering cross sections obtained in the same experiment.

The $n-d$ and $n-{\mathrm{}\left(\mathrm{np}\right)\mathrm{}}_{s=0\mathrm{}}$ triton $s$-wave asymptotic normalization constants are calculated from a realistic one-boson-exchange model of the $\mathrm{NN}$ interaction. Both parameters are calculated from integral relations which make the analytic continuation to the pole unambiguous. The values obtained are ${C_t}^2=2.60\mathrm{}$ and ${C_s}^2=-0.69\mathrm{}$.

Proton-induced carbon $K$ x-ray yields, measured for a wide variety of C-bearing gases at 2 MeV, vary more than 25%. A simple statistical model, based on estimates of the number of valence electrons with $p$ character available to fill a $K$ vacancy, gives good quantitative agreement with experimental results.

Low-power (<50 W) lower-hybrid waves excited in a linear plasma were observed to drive electron currents (a few milliamperes per watt) in the direction of the wave momentum when the waves were collisionally damped. An approximate solution of an electron kinetic equation with a Lorentz collision operator predicts an electron current in this experimental regime ($\frac{k_{\parallel }{v}_t}{\omega }\sim \frac{\nu }{\omega }\ll 1$).

This Letter predicts, on the basis of the structure of mode-coupling equations, that if the plasma $\beta$ exceeds the square of the inverse aspect ratio, ${\left(\frac{a}{R}\right)}^2$, the cross-magnetic-field diffusion is greatly enhanced by the appearance of convective cells even in the presence of magnetic shear.

Ohmic-current-driven magnetohydrodynamic instabilities in the Heliotron-D device, which has large external rotational transform ($t_F>1\mathrm{}$) and strong shear ($\theta >0.5\mathrm{}$), have been studied experimentally. Since those instabilities satisfy the regular relations between the external and the ohmic-current transforms ($t_{\mathrm{OH}}$), kink and resistive tearingmode instabilities are supposed to exist. The strong shear plays a major role to suppress the magnetohydrodynamic instabilities, and the Ohmic current exceeds the $t_{\mathrm{OH}}$ limit stably.

It is shown that ionic conductivity in ${\left(\mathrm{AgI}\right)}_x{\left({\mathrm{Ag}}_2\mathrm{O}·{\mathrm{B}}_2{\mathrm{O}}_3\right)}_{1-x}$ amorphous compounds is describable as a coupling between disorder modes of glass-forming borate units and ${\mathrm{Ag}}^{+}$ translational degrees of freedom. A model is presented for the ionic conductivity where ions and disorder modes are represented by two pseudospin variables which interact through an exchange term. This model, as applied to the interpretation of conductivity activation energies and prefactors in borate glass systems, is discussed.

The hcp-fcc transition in ${}_{}{}^4{}_{}{}^{}\mathrm{He}$ was investigated from 4 to 8.69 kbar by an optical method. The temperature hysteresis increases from 1 to 2.8 K, and the temperature width of the transition from 100 mK to about 2 K. The estimated equilibrium phase-transition line deviates increasingly with higher pressures from theoretical predictions.

We measure diffuse x-ray scattering close to Bragg reflections in aluminum single crystals after irradiation with fast-reactor neutrons at 4.6 K. Detailed evaluation of the results for low irradiation dose demonstrates that defects are located in cascades (radius $r_K\approx 50$ Å; defect number, $Z_K\approx 200$). Within a cascade the defects form agglomerates ($r_A\approx 5$ Å, $Z_A\approx 3$). For irradiation doses >2.4×${10}^{18}$ n/${\mathrm{cm}}^2$ the cascades partly overlap.

Inelastic neutron scattering from helium adsorbed on Graphon indicates the presence of two types of excitations: one bulklike, which appears to be associated with the normal density part of the film; and a second, at lower energy, which is thought to originate in the high-density liquid layer immediately adjacent to the solid layers of the film. The latter is believed to be responsible for the reduced roton gap inferred from bulk studies of few-atomic-layer superfluid films.

Measurements and analysis of heat capacity for ${}_{}{}^3{}_{}{}^{}\mathrm{He}$ in ${}_{}{}^4{}_{}{}^{}\mathrm{He}$ films at temperatures below 350 mK are reported. The data show that ${}_{}{}^3{}_{}{}^{}\mathrm{He}$ is less bound to the free surface of the ${}_{}{}^4{}_{}{}^{}\mathrm{He}$ film than to the bulk ${}_{}{}^4{}_{}{}^{}\mathrm{He}$ surface, and that it has a larger effective mass. Both of these parameters depend on ${}_{}{}^3{}_{}{}^{}\mathrm{He}$ surface coverage. The ${}_{}{}^3{}_{}{}^{}\mathrm{He}$ dissolved within the film behaves as a two-dimensional system for sufficiently thin ${}_{}{}^4{}_{}{}^{}\mathrm{He}$ films.

The Raman spectra of very thin evaporated films (∼6 nm thick) of metallic titanium and oxidized titanium are obtained with a new technique called interference-enhanced Raman scattering. The results indicate that titanium films exhibit a crystalline hcp structure while the titanium oxide has an amorphous structure with local atomic bonding configurations similar to those in crystalline ${\mathrm{Ti}}_2$${\mathrm{O}}_3$.

It is shown by theoretical arguments and lattice-model computations that when an fcc crystal is loaded uniaxially in tension along a [100] direction, a path of minimum energy (under strict [100] uniaxial load) takes the crystal into unstressed bcc.

The bond-charge dielectric theory of Phillips and Van Vechten is applied to the calculation of the electro-optic tensor coefficients. The agreement of the theoretical predictions with experimental values in the case of zinc blende and wurtzite crystals is very good.

Electronic states at the metal-silicon interface have previously been postulated in order to explain the pinning of the Fermi level, and the origin of these states has been a matter of some dispute. We propose here that in a reactive interface, such as the interface between Si and transition metals, physical properties of the interface are related to an interfacial layer, and that the relationship is manifest through the correlation between Schottky barrier height and eutectic temperature.