In a study of $K\overline{K}$ pairs produced in ${\pi }^{-}p$ interactions from 1.5 to 4.2 BeV/c, we observe the ${K_1}^0{K_1}^0$ threshold enhancement at all beam momenta, and the $\varphi$ meson at beam momenta below 2.3 BeV/c. There are no significant enhancements in the $K^0{K}^{-}$ system near threshold.

A precision measurement of the energy dependence of the asymmetry of the decay of the positive muon has been made with a wire spark-chamber spectrometer of large momentum acceptance. We find, as an average of runs at different fields and with different targets, $\delta =0.758\mathrm{}\pm 0.010$, in agreement with the two-component neutrino theory.

New relations between meson-baryon and baryon-baryon cross sections are found by making use of predictions for scattering on deuteron targets. These are in better agreement with experiment than previously derived relations and provide a better parametrization for the quark-model amplitudes. They show that universal coupling of $\omega$ and $\varphi$ Regge trajectories to mesons and baryons is a good approximation, but that the ratio of the two couplings is about 20% greater than predicted by SU(3) and SU(6).

We have observed and measured as a function of scattering angle ($0.33°<~\ominus <~3°$) the spectrum of light scattered quasielastically from entropy fluctuations in a normal fluid (toluene), using a laser light source and a high-sensitivity optical heterodyne spectometer. The magnitude and angular dependence of the linewidth are in excellent agreement with the predictions of the Leontovitch-Landau-Placzek theory.

Quantum-mechanical polarizability data for O${\mathrm{H}}^{-}$ in KCl are combined with calculated equilibrium dipole-ordering data for a dilute system of dipoles in an NaCl-type lattice, and a comparison is made with low-temperature dielectric measurements on KCl: OH at ${10}^2$ cps.

In the presence of an external electric field, certain Raman-active vibration modes in diamond-type crystals also become infrared active, giving rise to an absorption proportional to the first-order change in the electronic polarizability per unit cell with the relative displacement of atoms, $\frac{\partial \alpha }{\partial u}$. We have observed such a transmission minimum and from its characteristics we have determined the electric-field-induced effective ionic charge and $\frac{\partial \alpha }{\partial u}$.

Lack of specific Nilsson states with low $K$ value for assignment of rotational bands observed in ${\mathrm{Hf}}^{177}$ and ${\mathrm{Hf}}^{181}$ between 1 and 2 MeV, together with cross-section measurements, suggest fragmentation of bands into a large number of vibrational components. It is suggested that the previously unobserved pairing vibrations, the $\beta$ vibrations, and the more common $K-2\mathrm{}$ gamma vibrations may be responsible.

One observed deviation from the expectations of the one-pion-exchange model in $\rho$-meson production has been presented as evidence for a new $T=0\mathrm{}$, $J=0\mathrm{}$ resonance. We show that a similar effect is seen in a state which cannot have $T=0\mathrm{}$ and, therefore, must have another explanation.

We have measured the decay parameters of ${\Sigma }^{+}\to n+{\pi }^{+}$. The decay occurs through the $p$-wave channel: ${\alpha }_{+}$ is small (+0.047 ± 0.07); the likelihood ratio $\frac{(\gamma =-1)}{(\gamma =+1)}$ is 2 × ${10}^4$. Defining $\varphi$ by ${\beta }_{+}=sin\varphi$, ${\gamma }_{+}=cos\varphi$, we find $\varphi =180\mathrm{}°\pm 30°$. Our result confirms the prediction that $s\left({{\Sigma }_{+}}^{+}\right)=0\mathrm{}$. It also excludes a violation of $T$ through a large "imaginary" $s$ amplitude.

On the basis of a definite result from a Kobzarev-Okun' experiment on coherent regeneration, and an optical model calculation, we present evidence that the ${K_L}^0$ is heavier then the ${K_S}^0$.

The hyperfine field distributions at both the host and the impurity nuclei in iron-rich Fe-Mn and Fe-V alloys have been examined by nuclear resonance techniques.