The pion spectrum for charged and neutral pions is investigated in pure neutron matter, by letting the pions interact with a neutron Fermi sea in a self-consistent scheme that renormalizes simultaneously the mesons, considered the source of the interaction, and the nucleons. The possibility of obtaining different kinds of pion condensates is investigated with the result that they cannot be reached even for values of the spin-spin correlation parameter, $g^{\prime }$, far below the range commonly accepted.

A quantal description of one side of the discontinuity in the energy ratio (Mallmann) plot $\frac{E\left(I\right)\mathrm{}}{E\left(2\right)\mathrm{}}$ vs $\frac{E\left(4\right)\mathrm{}}{E\left(2\right)\mathrm{}}$ for ground state bands of even-even nuclei is obtained by solving exactly a centrifugal stretchinglike Hamiltonian. Its relation to the Bohr Hamiltonian is discussed.

The energy $E_v$ of the virtual state of the triton on the second sheet is calculated. The inclusion of a three-nucleon force moves $E_v$ towards the n-d threshold. The n-d doublet scattering length $a_2$ is strongly correlated with $E_v$. This offers a possible explanation for the improvement of the theoretical value for $a_2$ when a three-nucleon force is included.

In this note we report our final results for the (${\pi }^{-}$,$\gamma \gamma$) capture mode in ${}_{}{}^{12}{}_{}{}^{}\mathrm{C}$ and ${}_{}{}^9{}_{}{}^{}\mathrm{Be}$ and comment on the discrepancy observed between theory and two experiments at large interphoton angles.

We have measured the half-life of ${}_{}{}^{26}{}_{}{}^{}\mathrm{Al}$ because data on ${}_{}{}^{21}{}_{}{}^{}\mathrm{Ne}$ production rates in meteorites has indicated that the half-life may have been too low by 30—40%. We produced ${}_{}{}^{26}{}_{}{}^{}\mathrm{Al}$ using the ${}_{}{}^{26}{}_{}{}^{}\mathrm{Mg}\mathrm{}(p,n)\mathrm{}{}_{}{}^{26}{}_{}{}^{}\mathrm{Al}$ reaction on thick natural Mg, the yield being calculated from cross section data. The activity of two such samples was measured with a Ge(Li) detector and the calculated half-life is $t_{\frac{1}{2}}=(7.8\mathrm{}\pm 0.5)\times {10}^5$ years, in agreement with the accepted half-life of ${}_{}{}^{26}{}_{}{}^{}\mathrm{Al}:t_{\frac{1}{2}}=(7.16\mathrm{}\pm 0.32)\times {10}^5$ years. Therefore, another explanation must be found for the anomalous ${}_{}{}^{21}{}_{}{}^{}\mathrm{Ne}$ production rate based on ${}_{}{}^{26}{}_{}{}^{}\mathrm{Al}$ ages in meteorites.

Thermodynamical models with various forms of partial transparency of nuclear matter are considered. It is shown that the introduction of transparency, however, significantly improves agreement with pion data concerning multiplicities and transverse momenta leads to a serious discrepancy with average rapidities of pions. Qualitative arguments are given that difficulties of the thermodynamical approach can be overcome if one assumes hydrodynamical expansion in the first stage of nuclear interactions.

It is shown that the partial cross section for the $E2\mathrm{}$ transition at 6415 keV in ${}_{}{}^{21}{}_{}{}^{}\mathrm{Ne}$ emitted following thermal neutron capture is extremely large if it is a result of resonance capture. The possibility of a direct $E2\mathrm{}$ contribution is explored. The cross section can be accounted for by direct capture if the effective charge appropriate for low energy electric quadrupole transitions is used.

The nuclear charge dispersion in the fission of ${}_{}{}^{236}{}_{}{}^{}\mathrm{U}$, calculated on the fragmentation theory, is shown to give large deviations from the hypothesis of unchanged charge density.

The effect of the finite pion size is included in pion-bag coupling and masses and radii of N, $\Delta$, $\rho$, $\omega$, and $\pi$ are computed by minimizing the bag energies. The results show that the radii are about 15% smaller than MIT bag model radii and are in good agreement with cloudy bag model values.

Difficulties associated with the determination of the nuclear potential at distances inside the fusion barrier radius are discussed. The critical distance model analysis of fusion excitation functions at high bombarding energies does not give a model independent measurement of the internuclear potential at small separations of interacting heavy nuclei.

Two recent papers have given optical potential descriptions for the elastic scattering of the ${}_{}{}^{16}{}_{}{}^{}\mathrm{O}$+${}_{}{}^{28}{}_{}{}^{}\mathrm{Si}$ system at energies near the Coulomb barrier, both of which manifest partial-wave resonances. Our comment is that there is at least one other potential that reproduces the measurements but which does not result in such resonances.

The specific example suggested by Cariñena and Sesma is shown to yield an infinite number of bound states in agreement with the general results claimed earlier by Ericson and Myhrer and by Mandelzweig, Gal, and Friedman, and in accordance with a rigorous proof given here.

The discrepancy between the results obtained by Gal and Mandelzweig and those published by us is shown to be due to an ambiguity in the definition of the radial wave function occurring whenever the velocity-dependent potential satisfies the criticality condition of Ericson and Myhrer. The non-Hermitian solutions predicted by these authors are closely related to that ambiguity.

We rectify some formulas in Bauhoff's paper and point out the uniqueness of the energy independent local (but angular-momentum dependent) potential equivalent to an energy dependent local optical potential.

We use the thermodynamic model to calculate subthreshold pion production seen in recent experiments.

The observed single-particle energies in ${}_{}{}^{132}{}_{}{}^{}\mathrm{Sn}$ are compared with three current models. For each of the three models the deviations from experiment in ${}_{}{}^{132}{}_{}{}^{}\mathrm{Sn}$ are found to be correlated with the corresponding deviations in ${}_{}{}^{208}{}_{}{}^{}\mathrm{Pb}$. Assuming a similar relation between ${}_{}{}^{100}{}_{}{}^{}\mathrm{Sn}$ and ${}_{}{}^{56}{}_{}{}^{}\mathrm{Ni}$, the proton binding energy of ${}_{}{}^{100}{}_{}{}^{}\mathrm{Sn}$ is predicted to be about 3 MeV.

The isoscalar giant quadrupole resonance and the giant monopole resonance in ${}_{}{}^{112}{}_{}{}^{}\mathrm{Sn}$ were identified at $E_x=13.3\mathrm{}\pm 0.2 \mathrm{MeV}\mathrm{and} 15.7\pm 0.3 \mathrm{MeV}$, respectively, using small angle inelastic scattering of 129 MeV alpha particles. The nuclear incompressibility parameters for the volume term ($K_{\mathrm{vol}}$), the surface term ($K_{\mathrm{surf}}$), and the symmetry term ($K_{\mathrm{sym}}$) were determined including ${}_{}{}^{112}{}_{}{}^{}\mathrm{Sn}$.