Magnetoreflection experiments have been carried out on pyrolytic graphite using circularly polarized radiation from an infrared gas laser source. From a preliminary analysis of the data we find that the carriers at point $K$ in the Brillouin zone are electrons rather than holes. Additional support for this conclusion is obtained from a reexamination of the cyclotron-resonance data of Galt, Yager, and Dail.

The variations of nuclear charge radii in isotopes of Nd were determined from $K$ x-ray isotope shifts. The results, $\delta 〈{\mathcal{r}}^2〉$, in ${\mathrm{F}}^2$ are ${\mathrm{Nd}}^{142-144}$, 0.32±0.02; ${\mathrm{Nd}}^{144-146}$, 0.26±0.03; ${\mathrm{Nd}}^{146-148}$, 0.03±0.04; and ${\mathrm{Nd}}^{148-150}$, 0.44±0.02. The odd-even staggering parameters for ${\mathrm{Nd}}^{143}$ and ${\mathrm{Nd}}^{145}$ were determined to be $\gamma =0.60\mathrm{}\pm 0.07$ and $\gamma =0.25\mathrm{}\pm 0.20$, respectively.

Static and dynamic electric quadrupole moments of the first $2^{+}$ states in ${}_{}{}^{194}{}_{}{}^{}\mathrm{Pt}$, ${}_{}{}^{196}{}_{}{}^{}\mathrm{Pt}$, and ${}_{}{}^{198}{}_{}{}^{}\mathrm{Pt}$ have been determined from Coulomb-excitation cross sections for the scattering of 42-MeV ${}_{}{}^{16}{}_{}{}^{}\mathrm{O}$ ions measured as a function of scattering angle. The results are compared with recent calculations performed by Kumar and Baranger.

It is shown that double-beta decay occurs in nature. The half life of ${\mathrm{Te}}^{130}$ is ${10}^{21.34\pm 0.12}$ yr.

We present experimental values of the ${(\pi -\Sigma )}_{I=0,1\mathrm{}}$ and $\overline{K}-N$ scattering lengths derived from a coupled-channel effective-range analysis of the reactions $\overline{K}+N\to (\overline{K}+N, \pi +\Sigma , \pi +\Lambda )$, and theoretical values obtained by use of the soft-meson estimates of the scattering lengths in a role similar to that of known subtraction constants. Agreement of theory with experiment is within experimental error except for the $I=0\mathrm{}$ $\overline{K}-N$ scattering length where the disagreement is by 40%.

A new series of experiments is described, involving two gravitational wave detectors spaced about 2 km. A number of coincident events have been observed, with extremely small probability that they are statistical. It is clear that on rare occasions these instruments respond to a common external excitation which may be gravitational radiation.

The ${\Sigma }^{+}$ magnetic moment has been measured and found to be $(2.1\mathrm{}\pm 1.0){\mu }_N$ by observing the precession of polarized sigmas in a magnetic field of 18.7 kG. The value is in agreement with SU(3) predictions.

The effect of $\rho -\omega$ interference on the leptonic decay of photoproduced neutral vector mesons is shown to be much larger than previously estimated. The experimental determination of the leptonic branching ratio of the $\rho$ is shown to be sensitive to the amount of interference of the $\rho$ and $\omega$.

In a bubble-chamber experiment we have observed a splitting of the "$A_2\mathrm{}\left(1300\right)\mathrm{}$" similar to that observed in the CERN missing-mass experiment. Analysis of the ${K_1}^0{K_1}^0$ system indicates that there are two different resonances in the "$A_2$" region.

We report a study of the reaction ${\pi }^{-}p\to {\pi }^{-}p{\eta }^0\to {\pi }^{-}p{\pi }^{+}{\pi }^{-}{\pi }^0$ at 5.0 BeV/c, which gives clear evidence for ${A_2}^{-}\to {\eta }^0{\pi }^{-}$. The observed branching ratio is $R=\frac{({A_2}^{-}\to {\eta }^0{\pi }^{-})}{[{A_2}^{-}\to {\left(\rho \pi \right)}^{-}]}=0.23\mathrm{}\pm 0.08$, and the observed polarization of the $A_2$ is $2{\rho }_{11}\simeq 1$, ${\rho }_{1^{-}1}={\rho }_{{}_{}{}^{-}{}_{}{}^{}11}\simeq 0.5$. We also obtain evidence for ${A_2}^{-}\to X^0{\pi }^{-}$ with an observed branching ratio of $\frac{({A_2}^{-}\to X^0{\pi }^{-})}{[{A_2}^{-}\to {\left(\rho \pi \right)}^{-}]}=0.07\mathrm{}\pm 0.03$.

The nucleon isovector Pauli radius $〈{R_{2V}}^2〉$ is calculated, using sidewise dispersion relations, to be significantly larger than the predictions of $\rho$ dominance, in accord with observation. It is also predicted that $〈{R_{2V}}^2〉$ is significantly larger than the pion charge radius $〈{R_{\pi }}^2〉$. Elastic scattering of pions from electrons at very high energies (viz. Serpukhov) will give a clear confrontation with this prediction.

In inelastic channels (charge exchange, etc.) at $t=0\mathrm{}$, moving-cut effects are found to be ≲5% of the Regge-pole effects. This result is based on a dynamical approximation. Our findings clarify the success of relations among total cross sections derived by taking into account Regge poles alone.

The cross section ${\sigma }_{2s}\left(\mathrm{H}\right)$ for the atomic collision reaction ${\mathrm{H}}^{+}+\mathrm{H}\mathrm{}\left(1s\right)\mathrm{}\to \mathrm{H}\mathrm{}\left(2s\right)+{\mathrm{H}}^{+}$ has been measured for proton energies between 3 and 23 keV. The data provide a relatively sensitive test of available cross-section calculations. Good agreement exists with a three-state atomic-eigenfunction expansion calculation that includes as an intermediate state only the $2s$ state about the target proton. The Born approximation fails to predict the measured energy dependence below 20 keV.

Ultraslow-motion NMR and plastic-flow-rate techniques, both applied here for the first time to diffusion in a molecular crystal, each yield an activation enthalpy for self-diffusion of ∼36 kcal/mol. Mechanical properties of so-called plastic crystals have long been considered anomalous, but the relation between diffusion and plastic flow shown here renders the creep properties as well understood as those in metals.

Tungsten filaments have been operated while immersed in He II at temperatures up to 2500°K, and electron currents as high as 0.5 μA have been produced in the superfluid, yielding densities of at least ${10}^9$ negative ions/${\mathrm{cm}}^3$. The fluid in the vicinity of the filament remains quiescent under these conditions as a result of a stable vapor film which forms around the filament.

We study the containment of particles in the loss cone of a magnetic-mirror machine by means of rf fields whose frequency slightly exceeds the maximum value of the ion cyclotron frequency within the plasma. We report computations which verify the adiabatic theory of this confinement system.

Echo phenomena were observed in normal and superconducting powdered metals. They are believed to be related to magnetoacoustic modes.

The magnetization-field-temperature ($\sigma -H-T$) behavior of nickel both above and below its Curie point $T_c$ is found to obey an equation of state in which $\frac{\sigma }{{|1-\frac{T}{T_c}|}^{\beta }}$ is uniquely related to $\frac{H}{{|1-\frac{T}{T_c}|}^{\beta +\gamma }}$, where $\beta$ and $\gamma$ are the critical exponents for the temperature dependence of the spontaneous moment and initial susceptibility, respectively.