A model of leptonic $\mathrm{CP}$ nonconservation is constructed. The electron may have a measurable electric dipole moment and a large triple-product correlation may be seen in exotic muon decays.

We show that, for a class of models in which the Higgs doublets which couple to the up quarks can communicate with those coupling to the down quarks only via mass mixing, the requirement that there should be no flavor-changing neutral processes at the tree level is stable under radiative corrections to the one-loop order. This also implies, in the context of effective-field theories, that we may use the low-energy Lagrangean to calculate one-loop corrections. At the two-loop level, however, heavy particles in the yet-unknown complete theory are likely to come into play.

We show that in the presence of a magnetic flux tube, the ground state of Dirac fermions carries a net angular momentum. We use a trace-identity analysis to calculate it. We find the induced angular momentum, for a flux tube with one quantum of flux, to be fractionized to $\frac{1}{8}$. This is the first example of an induced external quantum number.

A method is described for the calculation of derivative terms in the effective action to one loop. Sample calculations are made of the two- and four-derivative terms for a single scalar field, and of the two-derivative terms for $\mathrm{O}\mathrm{}\left(N\right)\mathrm{}$ scalar field theory.

We discuss the properties of a solution of the Yang-Mills-Higgs system which can be thought of as a monopole "bead" on a (stable) string. Such beads appear in a wide class of models. Their existence implies that locally opposite directions on a $Z_2$ string are distinguishable in several important ways.

We report the first observation and cross-section measurement of ${\nu }_e+e^{-}\to {\nu }_e+e^{-}$. Using neutrinos of energy less than 53 MeV, we observed 63±17 events consistent with $\nu +e^{-}\to \nu +e^{-}$, of which 51±17 events are assigned to ${\nu }_e+e^{-}\to {\nu }_e+e^{-}$. The resulting cross section, {[8.9±3.2(statistical) ±1.5(systematic)]×${10}^{-45\mathrm{}}$ ${\mathrm{cm}}^2$/MeV} $E_{\nu }$, agrees with standard electroweak theory, rules out constructive interference between weak charged-current and neutral-current interactions, and begins to indicate the existence of interference between these two interactions.

Two branches are observed feeding the ${38}^{+}$ level of the yrast line in ${}_{}{}^{158}{}_{}{}^{}\mathrm{Er}$. Two ∼1.2-MeV cascade transitions constitute a fast (∼1 ps) collective component, probably with only minor changes in shape and structure from those at lower spin. Four slower $\gamma$ rays (>2 ps) suggest a transition to a different shape and structure, most likely to an oblate ${46}^{+}$ state with all valence particles maximally aligned, a band termination.

Squeezed states of the electromagnetic field have been generated by nondegenerate four-wave mixing due to Na atoms in an optical cavity. The optical noise in the cavity, comprised of primarily vacuum fluctuations and a small component of spontaneous emission from the pumped Na atoms, is amplified in one quadrature of the optical field and deamplified in the other quadrature. These quadrature components are measured with a balanced homodyne detector. The total noise level in the deamplified quadrature drops below the vacuum noise level.

The confinement times of impurities in Ohmically heated tokamaks are shown to lengthen considerably as the density-limit boundary is approached and exceeded either by the increase of $n_e$ itself or by the lowering of $B_T$ or $I_p$. Observations made on the Texas tokamak indicate that a change in the balance of diffusion and inward convection mechanisms governing impurity transport precedes the onset of partial or major disruptions. These studies also explain the reason for the wide differences of impurity behavior previously observed among various tokamaks.

A space potential distribution which is positive at all radii has been measured in the research tokamak RENTOR. This is in sharp contrast to negative potential wells observed in other devices. The positive potential distribution is in qualitative agreement with the predictions of stochastic magnetic field theory.

The effect of the nonlocality of the electron transport due to steep temperature gradients on the Nernst advection of the magnetic field is studied, together with the converse effect of the magnetic field on the electron transport.

Binary mixtures of protonated and perdeuterated 1,4-polybutadiene have been examined by small-angle neutron scattering and are shown to exhibit an upper critical solution temperature. The scattering results above the critical temperature are described by the mean-field theory of de Gennes for homogeneous binary polymer mixtures. These results contradict the universally held assumption that mixtures of deuterated and protonated polymers of otherwise identical chemical structure form ideal solutions.

Brownian simulations of rods with variable diameter $d$ show that the rotational friction constant ${\beta }_{\mathrm{rot}}$ is the same in the limit $d\to 0$ as for a probe rod in a system in which vicinal rods interact with the probe but not with each other. This agreement seems to rule out cage models. A model based on the rapid dissipation of cage forces accounts for the observed dependence of ${\beta }_{\mathrm{rot}}$ on concentration $c$, length $L$, and $d$.

The OH-stretch Raman band of liquid water has been observed for the first time at high pressures and temperatures. A new single-pulse spontaneous Raman technique was used to obtain spectra from ${\mathrm{H}}_2$O shocked up to 26 GPa and 1700 K. Band-shape changes over the range 7.5-26 GPa are fitted well by a two-component mixture model. Intermolecular hydrogen bonding, dominant at 12 GPa, is nearly absent at 26 GPa. The spectra indicate that transport of ${\mathrm{H}}^{+}$ and O${\mathrm{H}}^{-}$ ions is most probably the mechanism for the electrical conductivity of shocked water.

Precursor-mediated molecular chemisorption and thermal desorption are examined by means of a lattice-gas model using a combination of time-dependent Monte Carlo simulations and deterministic rate equations. Lateral interactions between coadsorbates are assumed to be both pairwise additive and limited in range to nearest and next-nearest neighbors. The interrelationships among kinetics, energetics, and adsorbate overlayer structures are analyzed in detail. The method is applied to the interaction of molecular nitrogen with the Ru(001) surface.

We have succeeded in extinguishing the anomalous Kapitza transmission of phonons whose wave vector is normal to a surface treated by conventional means and handled in air. In the same experiments, phonons approaching the surface with oblique wave vectors are anomalously transmitted. We argue that these results demonstrate that the Kapitza anomaly is due to surface defects which couple to the phonon strain field.

The ferroelastic phase transition of ${\mathrm{}\left(\mathrm{KBr}\right)\mathrm{}}_{0.27}$${\mathrm{}\left(\mathrm{KCN}\right)\mathrm{}}_{0.73}$ has been studied by x-ray diffraction, ultrasonics, and inelastic neutron scattering. It is the first example of a cubic crystal where the elastic shear constant $C_{44}$ softens completely corresponding to the $m=2\mathrm{}$ universality class. $C_{44}$ and the Bragg intensities show a nonclassical critical behavior.

Disclination lines are observed in the biaxial nematic phase of the lyotropic system comprised of rubidium laurate, 1-decanol, and ${\mathrm{H}}_2$O. They are shown to have a uniaxial nematic core which couples to the anisotropic elastic field produced by the surrounding medium. This interaction makes the disclination lines tilt and break into zigzags. The tilt angle is measured in the vicinity of the uniaxial to biaxial nematic phase transition, and found to vary linearly with temperature, which is consistent with the classical behavior of this phase transition.

$S(Q, E)$ has been obtained for liquid ${}_{}{}^3{}_{}{}^{}\mathrm{He}$ for $Q$ values between 4 and 7 ${\mathrm{\AA }}^{-1\mathrm{}}$ at temperatures of 1.2 and 0.37 K. The higher-temperature data are useful in examination of the role of final-state effects on measurements of $S(Q, E)$. Fermi-liquid properties can be determined from the low-temperature results and the data are consistent with a Fermi temperature of 1.8±0.2 K.

The volume phase transition of submillimeter spherical isopropylacrylamide gels shows critical kinetic behavior near the critical point; the transition takes an infinite time, and the thermal expansion becomes infinitely large. At the critical point the gels also undergo internal critical density fluctuations as revealed by photon-correlation spectroscopy. The observation of critical kinetics along with critical dynamics clarifies the physical principle of the kinetics of gel volume change.