Incorporating the present experimental value of the $\Delta S=-\Delta Q$ amplitude into the $K^0$ $\mathrm{CP}$-nonconservation phenomenology, we find that solution II (${\eta }_{00}$ and ${\eta }_{+-}$ in opposite quadrants) is as viable as solution I ${\eta }_{00}$ and ${\eta }_{+-}$ in the same quadrant), though both have poor fits. Thus, if a $\Delta S=-\Delta Q$ amplitude is allowed, a clear choice between these two solutions cannot yet be made.

Glashow and Weinberg recently predicted on the basis of current-algebra considerations that a scalar $K^{*}$ meson may exist, having a mass below $K\pi$ threshold and decaying predominantly via the $K\gamma \gamma$ mode. We have searched for the production of this particle by scattering $K^{+}$ mesons from hydrogen near 1 BeV/c. We see no evidence for its existence, and we set upper limits on its production cross section.

The $\overline{p}-p$ elastic scattering at 6.9 GeV/c was studied by the analysis of antiproton film taken by the Brookhaven National Laboratory 80-in. hydrogen bubble chamber. The cross section of the elastic scattering was 14.7 ± 1.5 mb. The angular distribution showed a dip in the region of $-t\approx 0.6$ ${(\mathrm{G}\mathrm{e}\mathrm{V}/\mathit{c})}^2$ and a secondary maximum at $-t\approx 0.8$ ${(\mathrm{G}\mathrm{e}\mathrm{V}/\mathit{c})}^2$.

It is shown that in gauge-field models for the electromagnetic and weak hadronic currents, restrictions are imposed on the way the symmetry is broken if the algebra of currents is to hold. A modified form of Weinberg's second sum rule is proposed, and relations among vector-meson masses are obtained on the assumption of nonet symmetry for the currents.

After a brief summary of recently derived general results relating to the mapping of functions of noncommuting operators on functions of $c$ numbers, equations are given which describe the time evolution of the $c$-number equivalents (phase-space representations) of the density operator and of a Heisenberg operator. The evaluation of time-ordered functions of operators by $c$-number techniques is also briefly discussed.

A new Reggeized bootstrap scheme is proposed based on finite-energy sum rules and unitarity. Taking a simple $\rho$,$f$ bootstrap model in $\pi \pi$ scattering as an example, both the high- and low-energy amplitudes are calculated simultaneously.

We have measured the elastic scattering cross section of ${\pi }^{+}$ mesons on deuterium at 3.65 BeV/c. The differential cross section $\frac{d\sigma }{\mathrm{dt}}$ is presented out to $-t\approx 1$ ${(\mathrm{B}\mathrm{e}\mathrm{V}/\mathit{c})}^2$ and a comparison is made with the prediction of the constant-phase Glauber formula. The agreement is good except in the region of the (theoretical) minimum at $-t\approx 0.4$. Starting with the Glauber formula, a method is presented to relate this discrepancy to the phases of $\pi$-nucleon scattering in this region.

The quasiparticle model is applied to the study of low-energy $1^{+}$ levels in single-closed-shell nuclei. Some of their properties are discussed.

An experiment reported by Witteborn and Pallesen to search for compositional dependence of the gravitationally induced electric field near metals is criticized. It is argued that the null result of their experiment is expected and therefore cannot be interpreted as indicating compositional independence. The experiment does not test therefore the theory proposed by Dessler, Michel, Rorschach, and Trammell, under which a compositional dependence may be expected.

The essential point of this note is to establish the uniqueness of general relativity by postulating the derivability of the equations of motion from the (gravitational) field equations. It is also emphasized that even with regard to agreement with experiment (including cosmology) there exist, in my opinion, no compelling arguments against general relativity.

We summarize recent results on the properties of matter in intense magnetic fields which are believed to exist in gravitationally collapsed bodies. The equations of state of a Fermi gas in magnetic fields are presented; they are superpositions of quantities relevant to a one-dimensional gas if the density is low enough or the field strong enough. For laboratory matter, the transition field is approximately ${10}^9$ G.

The negative three-pion mass spectrum between 1.0 and 1.4 BeV has been examined in the reactions ${\pi }^{-}p\to p\left({\pi }^{-}{\pi }^{-}{\pi }^{+}\right)$, ${\pi }^{-}p\to p{\pi }^0\left({\pi }^{-}{\pi }^{-}{\pi }^{+}\right)$, and ${\pi }^{-}p\to n{\pi }^{+}\left({\pi }^{-}{\pi }^{-}{\pi }^{+}\right)$ for 5-BeV/c incident ${\pi }^{-}$. In each reaction peaks are observed near 1.06, 1.17, and 1.30 BeV.

A calculation of the $K_{l3\mathrm{}}$ form factors is done on the basis of current algebra, partial conservation of axial-vector currents (strangeness conserving), and dispersion relations. Assuming once-subtracted and unsubtracted dispersion relations for $f_{+}\left(q^2\right)+f_{-}\left(q^2\right)$ and $f_{+}\left(q^2\right)-f_{-}\left(q^2\right)$, respectively, and $K^{*}$ dominance, the $K_{l3\mathrm{}}$ decay parameters $\xi$, ${\lambda }_{+}$, and ${\lambda }_{-}$ are calculated. All results are consistent with the present experimental indications.

The treatment of a weak $u$ channel by the usual prescription of exchange degeneracy, based on a potential-theory model, is shown to violate crossing badly. On the other hand, a crossing-symmetric treatment of the same situation would lead to backward superconvergence relations, which provide the basis for a new prescription of exchange degeneracy. Several consequences of this crossing-symmetric prescription of exchange degeneracy are discussed, with particular reference to $N\overline{N}$ scattering.

A current-algebra calculation of the $K_{l3\mathrm{}}$ form factors is made under the assumption that the chiral SU(3) symmetry is broken by an interaction which transforms under the representation (3, 3*) ⊕ (3*, 3). Quantitative results on the weak decay parameters of the mesons, the $\kappa$ meson mass, and the form factor $f_{+}\mathrm{}\left(0\right)\mathrm{}$ are obtained. The factor $\xi$ is found to be very nearly zero.

Theory and experiments are presented to show that, when correctly interpreted, the sign of the dispersion-shaped term which describes a part of the change in resonance scattering at level crossings can be used to determine the energy ordering of the crossing levels, and hence, in some cases, to obtain the sign of the nuclear magnetic moment. Because of a discrepancy in the literature in the theoretical prediction for the sign of the dispersion-shaped term, we have made a recalculation. The result is borne out by our experiments.

In close encounters of the systems Ne-Ne, ${\mathrm{Ne}}^{+}$-Ne, and ${\mathrm{Ne}}^{++}$-Ne, electrons of 750-eV energy are produced. The numbers of such fast electrons are found to depend upon the charge state of the incident particle (0, +1, or +2) in the ratio of 0.6, 1.0, and 2.0, respectively. This agrees in part with a prediction by Lichten. In ${\mathrm{Kr}}^{+}$-Kr collisions, there is a sudden change in the average number of electrons lost for 9° scattering at 25-keV incident energy.

Photoirradiation of a rare-gas matrix at 4°K containing both electron donating species and electron accepting species of suitable choice may lead to generation and trapping of charged species effectively isolated within the matrix lattice. Preliminary investigation conducted along this line using certain metal atoms (Cd, Cr, Mn, and Na) as electron donors and HI as an acceptor led to successful observation of the electron spin resonance spectra of ${\mathrm{Cd}}^{+}$, ${\mathrm{Cr}}^{+}$, and ${\mathrm{Mn}}^{+}$.

We have studied the optically induced NMR effects in anthracene with different optical irradiation spectra and in various samples. Comparison of these results with measured exciton concentrations indicates that the anthracene mobile triplet exciton is not directly responsible for the observed NMR effects. Radiation-induced changes in the anthracene absorption and prompt fluorescence appear to be related to changes in the strength of the induced NMR effects.