Balloon observations of the cosmic-ray electron spectrum in 1966, 1967, and 1968 show a reduction of the electron flux between 500 MeV and 5 GeV with increasing solar activity.

We report the observation of one narrow ${\rho }^0{\pi }^{-}$ resonance in the $A_2\mathrm{}\left(1300\right)\mathrm{}$ mass region with a width of 40 MeV or less from the reaction $K^{-}n\to \Lambda {\rho }^0{\pi }^{-}$. A spin-and-parity analysis of this narrow enhancement favors $J^{\mathrm{PC}}=1^{-+}$. Branching ratios for other decay modes are also given.

A model based on a broken ($N_{\alpha },N_{\gamma }$) exchange degeneracy is proposed to explain the structureless data for the $\mathrm{pp}\to {\pi }^{+}d$ differential cross section. An effective Regge trajectory is determined which agrees with our prediction. Quantitative fits to the data are presented and physical aspects of the broken degeneracy are discussed.

We have studied the $\mathrm{ee}$, $e\gamma$, and $\gamma \gamma$ elastic-scattering amplitudes contributed by certain infinite sets of diagrams in the high-energy limit. They found to be proportional to $s$, the square of the c.m.-system energy, multiplied by simple combinations of the Glauber forms of high-energy scattering.

We derive a formula for the matrix element $〈K\left|{\partial }_{\mu }\mathcal{F}_a^{}{}_{}{}^{\mu }\right|\pi 〉$ correct up to second order in both the momentum transfer $t$ and the breaking of SU(3) ⊗ SU(3) symmetry. This leads to a prediction that $\xi$ is very small compared with unity. Our result is independent of any assumption concerning the structure of the symmetry-breaking Hamiltonian.

Relations between coupling constants derived from the Veneziano amplitude for $\pi K\to \rho K$ combined with a previous result, allow us to predict the (observed) suppression of the $K\overline{K}$ decay mode of the $A_2$ meson.

Lines of the kaonic x-ray spectra of 24 elements ranging from $Z=17\mathrm{}$ to $Z=92\mathrm{}$ have been measured. Kaons are absorbed at the nuclear surface from circular orbits. The sudden cutoff of transitions to successively lower principal quantum numbers at certain values of $Z$ indicates that nuclear matter (probably neutrons) extends above the conventional nuclear surfaces. A peak in one of the spectra corresponds to x rays from ${\Sigma }^{-}$-hyperonic atoms.

The requirement of an invariant velocity of a system of bosons describable by a non-relativistic grand-canonical potential is used to propose a gauge-invariant formulation of the grand-canonical system.

From the Langer and Fisher thermal-fluctuation theory we have determined the pressure-velocity dependence for pressure-driven intrinsic superfluid helium flow to be $p\propto \exp \left(\frac{-\beta {\rho }_s}{\rho v_s\mathrm{kT}}\right)$. Experiments of pressure-driven intrinsic flow through submicron pores in porous mica are in agreement with this relation.

The present investigation of a hot ($T_e \mathrm{and} T_i\ne 0$) magnetized plasma cylinder shows that ${\overrightarrow{\mathrm{B}}}_0$ can introduce novel features in the ion thermal resonances. Furthermore, two new and strong main resonances are obtained which occur in the ion domain and are essentially due to a proper combination of $T_e$ and $B_0$. These resonances of a bounded plasma are only indirectly connected to the lower and upper hybrid resonances of an infinite plasma.

We investigate the propagation and attenuation of torsional Alfvén waves in a nonuniform, resistive, cylindrical plasma with conducting boundary. The nonuniformity leads to increased damping and makes it difficult to launch a pure mode.

We derive a consistency condition for the linear-response formulation of transport phenomena in a strong magnetic field. It is shown that despite the convergent results obtained for the transport coefficients this formulation may be totally inconsistent and yield in fact divergent corrections to the occupation probabilities. The relation of this previously unrecognized difficulty to irreversible kinetic theory is established.

The self-consistent phonon formalism, successful in the description of the quantum crystals ${\mathrm{He}}^3$ and ${\mathrm{He}}^4$, is here applied to a discussion of the soft $k=0\mathrm{}$ TO mode in SnTe. Straightforward considerations allow us to arrive at a simple expression for $\omega _{\mathrm{TO}}^{}{}_{}{}^2\mathrm{}(k=0\mathrm{})\mathrm{}$ in the low-temperature regime. The analysis permits a quantitative fit to the temperature dependence of $\omega _{\mathrm{TO}}^{}{}_{}{}^2\mathrm{}(k=0\mathrm{})\mathrm{}$ over a rather wide range of temperature.

The microwave emission from $n$-type InSb in crossed magnetic and low electric fields at nitrogen temperature was investigated experimentally. It was found that the emission was caused by a helical instability of a high-current filament formed at an electrode contact.

We report neutron measurements of the magnetic disorder scattering cross section for ${\mathrm{Ni}}_{0.8}$${\mathrm{Cu}}_{0.2}$. These indicate that the magnetic moment disturbance produced by Cu in Ni is essentially limited to first-neighbor effects.

The fcc phases of Pr and Nd have been stabilized at room temperature and at liquid-helium temperatures and both prove to be ferromagnetic. The measured electronic properties of this new phase are discussed in the light of presently accepted phase diagrams. The existence of the fcc phase accounts for a variety of anomalous data reported for double-hcp Pr.

A high-precision molecular-beam-resonance experiment has been carried out to look for a violation of $P$ and $T$ invariances in a molecule. The null result can be interpreted in terms of the electric dipole moment of the proton to give $\left|d_p\right|=(7\mathrm{}\pm 9)\times {10}^{-21\mathrm{}}$ e cm.

The differential cross sections for the elastic scattering of negative pions by deuterons have been measured for 2.01-, 3.77-, and 5.53-GeV/c incident pion momenta, over an interval of the squared four-momentum transfer from -0.25 ${(\mathrm{G}\mathrm{e}\mathrm{V}/\mathit{c})}^2$ to ∼-1.0 ${(\mathrm{G}\mathrm{e}\mathrm{V}/\mathit{c})}^2$. The results are consistent with calculations based on a Glauber model of the scattering process.

If the decays ${\eta }^0\to {\pi }^0{l}^{+}{l}^{-}$ occur via a $C$-nonconserving (isovector) electromagnetic interaction, the ratio $\frac{\Gamma ({\eta }^0\to {\pi }^0{e}^{+}{e}^{-})}{\Gamma ({\eta }^0\to {\pi }^0{\mu }^{+}{\mu }^{-})}$ should be 3.3. Similarly, if the decays $X^0\to {\eta }^0{l}^{+}{l}^{-}$ are induced by a $C$-nonconserving (isoscalar) interaction, the ratio $\frac{\Gamma (X^0\to {\eta }^0{e}^{+}{e}^{-})}{\Gamma (X^0\to {\eta }^0{\mu }^{+}{\mu }^{-})}$ should be 2.9.