A search was made for a possible variation in the inertial mass of platinum with respect to that of magnesium produced by the application of a centrifugal field. No variation was found within an experimental uncertainty of 4 parts in ${10}^5$ due to the application of a centrifugal field of $1.5\times {10}^{5}g$ or within 3 parts in ${10}^{10}$ per $g$.

The asymmetry parameter ${\alpha }_0$ for ${\Lambda }^0\to n{\pi }^0$ has been measured relative to ${\alpha }_{-}$ by comparing the neutron distribution with the proton distribution from the decay ${\Lambda }_0\to p{\pi }^{-}$ for polarized ${\Lambda }^0$ hyperons. A sample of 4760 neutron decay events and 8500 proton decay events gave $\frac{{\alpha }_0}{{\alpha }_{-}}=1.000\mathrm{}\pm 0.068$ in good agreement with the $\left|\Delta \overrightarrow{\mathrm{I}}\right|=\frac{1}{2}$ rule.

We have studied the $\mathrm{ep}$ deep inelastic scattering in a neutral pseudoscalar-meson theory without imposing a cutoff on the transverse momentum, by summing an infinite set of diagrams. The main results are that (1) the final particles fall naturally into two jets, (2) the Bjorken scaling law breaks down, (3) multiplicity of pions increases as $log{q}^2$, and (4) a longitudinal impact parameter space is realized.

It is suggested that the leading fixed-pole terms in virtual Compton amplitudes are polynomial functions of the photon mass variable $q^2$.. Several arguments are given in support of this conjecture. Implications of this behavior in the calculation of the electromagnetic mass differences and in the $q^2$ dependence of the $e-p$ inelastic-scattering structure functions are discussed.

A study is made of the additional information learned from measurements of the correlation of two (or more) detected particles in the final states of deep inelastic lepton processes. Generalized Bjorken limits are derived in which the new structure functions depend only on the ratios of the kinematical variables available, just as do the more familiar structure functions $W_1$ and $\nu W_2$ for electron-proton scattering in the deep inelastic region. Experimental implications are discussed.

A variational calculation is presented of the tensor polarizability of the helium $2{}_{}{}^3{}_{}{}^{}S_1^{}{}_{}{}^{}$ state. The theoretical value ${\alpha }_t=(3.48\mathrm{}\pm 0.01)\times {10}^{-3\mathrm{}}$ a.u. lies within the error limits of recent experimental measurements.

We show that the dispersion energy ${\mathcal{E}}_d$, as defined by Wemple and DiDomenico, is independent of $E_g$ as long as ${\epsilon }_2$ is of the form ${\epsilon }_2\mathrm{}\left(E\right)={E_g}^{-1\mathrm{}}g\left(\frac{E}{E_g}\right)$. For a different choice of model than the one chosen by Wemple and DiDomenico, the constancy of ${\mathcal{E}}_d$ within certain groups of crystals can be interpreted in terms of similarity of band structure for crystals within one such group.

The influence of magnetic interactions among the conduction electrons in metals on the dispersion and damping of helicon waves is studied.

Spin-wave theories of antiferromagnets predict a zero-point spin deviation from the completely ordered state. In antiferromagnetic ${\mathrm{K}}_3$Fe${\mathrm{}\left(\mathrm{CN}\right)\mathrm{}}_6$, a spin deviation of approximately 18% has been observed by the Mössbauer spectra of ${}_{}{}^{57}{}_{}{}^{}\mathrm{Fe}$.

The spin of the 5.256-MeV level in ${\mathrm{Si}}^{29}$ has been determined to be $J=\frac{9}{2}$; its mean lifetime has been measured to be ${\tau }_m=(0.95\mathrm{}\pm 0.15)\times {10}^{-13\mathrm{}}$ sec. The electromagnetic decay of this state is >90% via cascade radiation through the $J^{\pi }={\frac{7}{2}}^{-}$ state of ${\mathrm{Si}}^{29}$ at 3.624 MeV, with $E_{\gamma }=1631.3\mathrm{}\pm 0.5$ keV; the transition has quadrupole/dipole admixture $\delta =-0.49\mathrm{}\pm 0.07$. This multipole mixing together with the measured lifetime fix parity $\pi =-1\mathrm{}$ for this state.

The magnitude of the expected superfluid transition temperature and the form of the gap are obtained for regimes of neutron density expected in neutron-star cores. For neutron densities exceeding 1.5×${10}^{14}$ g ${\mathrm{cm}}^{-3\mathrm{}}$ the gap is anisotropic but nodeless, leading to thermodynamic properties of a conventional BCS-type superfluid.

Evidence is presented for the decay of the $\Xi \mathrm{}\left(1820\right)\mathrm{}$ and $\Xi \mathrm{}\left(1930\right)\mathrm{}$ resonances to $\Xi \mathrm{}\left(1530\right)\mathrm{}\pi$, and for an $I=\frac{1}{2}$ assignment to these states. By combining data from the $\Xi \pi$ and $\Xi \mathrm{}\left(1530\right)\mathrm{}\pi$ decays of these resonances, we have determined their masses (1820 ± 7, 1963 ± 8) MeV, widths (64 ± 23, 89 ± 33) MeV, and branching ratios [$\frac{\Xi \pi }{\Xi \mathrm{}\left(1530\right)\mathrm{}\pi }={1.5}_{-0.4\mathrm{}}^{+0.6\mathrm{}}, {2.8}_{-0.6\mathrm{}}^{+0.7\mathrm{}}$].

We have observed, in a high-statistics experiment, well-defined threshold enhancements in the ${\rho }^0{\pi }^{-}$ and $f^0{\pi }^{-}$ systems at 1120 and 1645 MeV, respectively. We have searched for other dominant decay modes of these enhancements and found none. The question of whether these objects are threshold enhancements of kinematic origin or resonances is examined.

We present results of measurements on photoproduction of $\rho$ mesons. Analysis of ${10}^6$ measured $\rho$ events in a four-dimensional data matrix $\frac{d\sigma (A, m, p, t_{\perp })}{d\Omega \mathrm{dm}}$ with dimensions 14×20×10×20 yields precise information on nuclear density distributions for $\rho$ production. We obtain for the Woods-Saxon radii $R\left(A\right)=(1.12\mathrm{}\pm 0.02)A^{\frac{1}{3}}$ and, using the vector dominance model, ${\sigma }_{\rho N}=26.7\mathrm{}\pm 2.0$ mb and $\frac{{{\gamma }_{\rho }}^2}{4\pi }=0.57\mathrm{}\pm 0.10$.

We present results on the determination of a set of strong-interaction nuclear radii using the photoproduction of neutral rho mesons. Analysis of ${10}^6$ events from 13 complex nuclei yields the Woods-Saxon radii $R\left(A\right)=(1.12\mathrm{}\pm 0.02)A^{\frac{1}{3}}$ fm.

30-MeV I ions were scattered by thin targets of Yb and Te. The differential and total cross sections for characteristic x-ray production were measured. The mechanism responsible for inner-shell ionization is suggested to be electron promotion by level crossing in the quasimolecule of the colliding atoms.

A traveling Auger detector is used to measure the attenuation of a cooled thermal beam of He $2{}_{}{}^1{}_{}{}^{}S$ atoms in a vacuum of 1×${10}^{-8\mathrm{}}$ Torr. Its velocity is determined by a time-of-flight technique. The lifetime obtained is (38 ± 8)×${10}^{-3\mathrm{}}$ sec.

The lifetime of the $v=2\mathrm{}$ level of the $A{}_{}{}^1{}_{}{}^{}\Pi$ state of CO has been measured by molecular level-crossing spectroscopy. Unlike previous experiments with molecules in which the Hanle effect has been analyzed for individual rotational states, the present results are obtained from analysis of the composite level-crossing signal from all of the rotational states which are excited by the entire $A\to X(2, 0)$ resonance band. Our experimental result is $\tau \mathrm{}(v=2\mathrm{})=9.0\mathrm{}\pm 1.0$ nsec in good agreement with Hesser's value of 10.5 ± 1.0 nsec obtained from phase-shift experiments.

Isotopic substitution of ${\mathrm{Li}}^6$ has made it possible to measure the electric field perturbation of the hyperfine interaction of $F$ centers in lithium fluoride.

The change in the logarithmic decrement upon applying heat to a freely oscillating cylinder in He II has been measured. After corrections, caused by heat, in the normal viscous contribution to the decrement the results are used to verify the prediction by Penney and Overhauser that a torque should exist on a uniformly heated cylinder about which there is a superfluid circulation. A critical comparison is made between the results of the present experiment and the prior work of Hunt who employed a quite different method.