Giant-resonance-like peaks showing systematic variations with neutron number have been observed in the ($d, t$) reaction on the even-$A$ tin isotopes. In the reaction ${}_{}{}^{116}{}_{}{}^{}\mathrm{Sn}(d, t){}_{}{}^{115}{}_{}{}^{}\mathrm{Sn}$ a separation of the $g_{\frac{9}{2}}$ and $p_{\frac{1}{2}}$, $p_{\frac{3}{2}}$ neutron-hole components has been obtained. A calculation of the hole spectral function shows that shell effects play an important role in determining the spreading width.

It is shown that nuclear (as opposet to Coulomb) rainbow-scattering data would be useful in discriminating among heavy-ion optical potentials. Acquisition of such data is facilitated by going to higher bombarding energies and using low-$A$ targets.

We have studied production of ${\pi }^0$ with transverse momentum between 2.0 and 4.4 GeV/c at 65 and 93° in the c.m. system in 300-GeV proton-nucleon collisions, by inserting foils of various thicknesses into a secondary beam and measuring the electron and positron spectra produced by $\gamma$ conversion. The ${\pi }^0$ invariant cross sections are given at 93 and 65°. We also report invariant cross sections for negatively charged hadrons as a function of transverse momentum.

Direct production of electrons and muons is observed in 300-GeV $p$-Be collisions. The yields are much higher than predicted from current models. Data are consistent with charge symmetry and universality.

We present results of measurements of the $n-p$ total cross section between 30 and 280 GeV/c. The measurements were carried out with a neutron beam by using the standard transmission technique and a liquid-hydrogen target. A total-absorption calorimeter was used to determine the neutron energy. Our measurements, which have an accuracy of ∼1%, indicate a smooth rise of approximately 1.5 mb between 50 and 280 GeV/c. The combined $n-p$ and $p-p$ data above 20 GeV/c are well fitted by the expression $\sigma =38.4+0.85\mathrm{}{\left|\ln \right(\frac{s}{95}\left)\right|}^{1.47}$ mb.

We suggest a form of the off-shell pion-nucleon amplitude which is motivated by simple field-theoretic considerations. This amplitude contains a momentum-dependent form factor $v\left(k\right)\mathrm{}$ which we determine by solving an inverse scattering problem, using the experimental phase shifts and inelasticities as input.

Data are presented which demonstrate that the laser light scattered from the protoplasm of living algae cells is Doppler shifted by the streaming motion of the macromolecules and particles in the protoplasm. The laser-light-scattering spectra are used to determine the velocities and velocity distributions inside the cells.

We show that a finite cutoff of the hydrodynamic modes (order fluctuations) in the nematic liquid-crystalline phase explains the measured spin-lattice relaxation in this phase. A calculation of $T_1$ based upon such a cutoff and a fit to the data of MBBA (4-$n$-methoxybenzylidene-4′ -$n$-butylaniline) show this cutoff to be 1 molecular length. At $T_{1\rho }$ frequencies, far from the cutoff, order fluctuations are shown to be the dominant relaxation mechanism. This is done by comparing the predicted angular dependence of $T_{1\rho }$ for these modes with that measured in MBBA.

The magnetic anisotropy of the $B$ phase (assumed to be a Balian-Werthamer phase) is investigated within the Landau-Ginzburg theory. The anisotropy is determined by the action of the dipolar energy and the magnetic field on a single vector $\overrightarrow{\mathrm{n}}$ and it is shown that walls will induce variations in $\overrightarrow{\mathrm{n}}$ on a scale of $R_C\sim 0.1$ cm. In the presence of a field $H$ this characteristic length becomes $\frac{R_C{H}_B}{H}$, where $H_B$ is of the order of 100 Oe.

We describe a nuclear demagnetization cryostat in which liquid ${}_{}{}^3{}_{}{}^{}\mathrm{He}$ has been cooled to below 0.7 mK. Data on the boundaries between the normal Fermi-liquid and the superfluid phases of ${}_{}{}^3{}_{}{}^{}\mathrm{He}$, as determined from NMR measurements, are presented between 0.7 and 2.5 mK and from 0 to 27 bar. The "$\lambda$ point" of ${}_{}{}^3{}_{}{}^{}\mathrm{He}$ was found at 0.93 mK.

Fourth sound has been generated and detected in the superfluid phases of liquid ${}_{}{}^3{}_{}{}^{}\mathrm{He}$ by means of a new technique.

Time-resolved and time-integrated measurements of the energy, spectra, and other characteristics of the backscattered laser radiation from a laser-produced plasma are presented. Theoretical comparison shows that most of these measurements are consistent with the stimulated-Brillouin-backscattering instability.

The period of the Peierls distortion in a one-dimensional system is assumed to be incommensurate with the lattice. The fluctuation conductivity just above the mean-field transition temperature is calculated in the presence of electron-impurity scatterings. In the clean limit for sufficiently strong electron-phonon interaction, the conductivity is enhanced by fluctuations whose contribution is impurity limited and goes like ${(T-T_{\mathrm{P}})}^{-\frac{1}{2}}$ in the leading approximation. In the dirty limit, the conductivity is reduced by fluctuations.

Thermal fluctuations of the type described by Langer and Ambegaokar and by McCumber and Halperin have been observed in superconducting thin-film rings containing microbridge sections. A peak in the fluctuation rate was found near the transition temperature. The temperature dependence of the observed rates is in agreement with the McCumber-Halperin fluctuation-rate equations and the deduced parameters are consistent with the theory.

The thermoreflectance spectrum of gold has been measured in the 6-35-eV region at about 200 K by using synchrotron radiation. Considerable sharp structure exists throughout this region, showing that lifetime broadening is not large enough to preclude the extension of high-resolution modulation techniques to at least 35 eV. The structure arises from interband transitions of the $5d$ electrons and from plasmons.

The cohesive energy of the electron-hole drop in germanium at 1.5 K is determined as a function of uniaxial stress, both along $〈100〉$ and along $〈111〉$ directions, by the method of cyclotron-resonance monitoring at 35 GHz. On application of stress, it starts decreasing from the value of 14.5 K at zero stress, but has an air of persisting to have a finite value at a considerably high-stress region.

Resonant scattering of electrons on optical phonons in inverted band structure is considered. It is proved that in intrinsic samples transition of the electrons from the conduction band to the valence band with simultaneous emission of optical phonons can cause a minimum of the conductivity. Such a scattering process explains the anomalous behavior of conductivity versus temperature in mercury telluride in the 30-50 K range.

The energy-loss spectra of ∼ 100-eV electrons were measured for (100) and ($\overline{1}\overline{1}\overline{1}$) GaAs and (111) Ge surfaces. The portion of the energy-loss spectra attributed to excitations of $d$ electrons is proportional to the density of states in the conduction bands and empty surface states. The GaAs surfaces stabilized into Ga-rich and As-rich conditions permit unambiguous identification of intrinsic surface states. Empty and filled surface states, attributed to dangling Ga and As bonds, are observed near the conduction-band and valence-band edges, respectively.

Cross sections and polarizations have been measured for ${}_{}{}^{14}{}_{}{}^{}\mathrm{C}(p, p){}_{}{}^{14}{}_{}{}^{}\mathrm{C}$ scattering over the energy range corresponding to the giant-dipole-resonance region of ${}_{}{}^{15}{}_{}{}^{}\mathrm{N}$. The results indicate a $J^{\pi }={\frac{3}{2}}^{+}$ resonance of about $\Gamma =4\mathrm{}$ MeV near $Ep=10\mathrm{}$ MeV. This resonance appears to be the giant dipole resonance observed in ($p, \gamma$) measurements.

Proton-nucleus interactions in nuclear emulsion from a 200-GeV proton beam at the National Accelerator Laboratory have been studied in terms of multiplicities and the angular distributions of shower particles. Low multiplicities observed in complex nuclei do not depend upon the size or the excitation of the target nuclei. Our experimental results are explained in terms of the energy-flux cascade model and not by intranuclear cascade models.