We have evaluated the cross section for the ${\mathrm{\pi }}^{\mathrm{-}}$+A→${\mathrm{\pi }}^{+}$+(A${\mathrm{\pi }}^{\mathrm{-}}$) reaction in heavy nuclei producing deeply bound ${\mathrm{\pi }}^{\mathrm{-}}$ atom states still unobserved. The cross sections found, although in the measurable range, are only a small fraction of the background from the inclusive (${\mathrm{\pi }}^{\mathrm{-}}$,${\mathrm{\pi }}^{+}$) reaction, which makes this experiment not very suited for the investigation of these elusive pionic states.

The p${\mathrm{-}}^{40}$Ca mean field is derived from an optical-model (OM) analysis that explicitly incorporates the dispersion relation connecting the real and imaginary parts of the mean field. This analysis is based on differential cross-section, analyzing power, and reaction cross-section data available in the energy range between 20 and 180 MeV. The extrapolation of the OM potential from positive to negative energies provides the shell-model potential. This extrapolation is guided by known single-particle energies. The deeply bound 1p and 1s orbits clearly indicate the need for a linear rather than an exponential energy dependence of the Hartree-Fock potential at large negative energies. The analysis also provides root-mean-square radii, occupation probabilities, spectral functions, and absolute spectroscopic factors for proton single-particle orbits in ${}_{}{}^{40}{}_{}{}^{}\mathrm{Ca}$. Our calculated 15% depletion of the hole states in ${}_{}{}^{40}{}_{}{}^{}\mathrm{Ca}$ is lower than that suggested for ${}_{}{}^{208}{}_{}{}^{}\mathrm{Pb}$ from theoretical and experimental studies. We also find that a substantial amount of single-particle strength in ${}_{}{}^{40}{}_{}{}^{}\mathrm{Ca}$ is located at rather high excitation energy.

The transient behavior of the fission rate at deformations beyond saddle point is studied and it is found that the ‘‘overshooting’’ disappears at these deformations. The neutron numbers and the neutron multiplicity in the decay chain are also calculated. The number of neutrons is found to decrease linearly as the atomic number decreases. The neutron multiplicity is found to be approximately proportional to the logarithm of the friction constant. From comparison with the measured neutron multiplicity of ${}_{}{}^{16}{}_{}{}^{}\mathrm{O}$${+}^{142}$Nd${\to }^{158}$Er at 207 MeV, we deduce that the friction constant is about (3–6)×${10}^{21}$ ${\sec }^{\mathrm{-}1}$.

Calculations are presented for electric quadrupole excitations in relativistic nucleus-nucleus collisions. The theoretical results are compared to an extensive data set and it is found that electric quadrupole effects provide substantial corrections to cross sections, especially for heavier nuclei.

The effects of the small components of Dirac spinors, used to describe quark and antiquark wave functions in clusters, and the Lorentz contraction of cluster wave functions associated with the Lorentz transformation to the overall center of momentum frame are considered in the proton-antiproton annihilation into two final state mesons. A quark-antiquark pair annihilation and creation model in the planar picture that reproduces the principly observed final states in the nonrelativistic case is used. The effects are studied by taking the nonrelativistic model as a base of comparison. The introduction of small components in the quark wave functions has little influence on predictions of relative ratios of annihilation amplitudes into final state mesons in the same relative angular momentum state of the initial proton and antiproton. In contrast, the small components give a large contribution to the absolute value of the annihilation amplitude in dependence on the initial relative angular momentum. The effects of including the Lorentz contraction of the cluster wave functions appear in the annihilation amplitudes of two meson final states. By using Lorentz transformed Gaussian wave functions for the clusters, subsequent effects on the annihilation amplitudes into two mesons, such as ππ, ρπ, and ρρ, are studied. For a nucleon radius of 〈${\mathit{r}}^2$${\mathrm{〉}}_{\mathit{N}}^{1/2}$=0.62 fm and a global meson radius of 〈${\mathit{r}}^2$${\mathrm{〉}}_{\mathit{M}}^{1/2}$=0.50 fm, the production of two final state pions is enhanced upon including the Lorentz contraction effects.

Tests of isospin symmetry in (n,p), (p,p’), and (p,n) reactions at 280 MeV populating the T=1 isospin triads in A=6 and A=12 nuclei have been performed. Distorted-wave impulse approximation (DWIA) calculations for the A=12 triad where the known ft asymmetry is included in the analysis show good agreement with experimental (n,p) and (p,p’) data. Angular distributions for ${}_{}{}^6{}_{}{}^{}\mathrm{Li}$(n,p) and ${}_{}{}^6{}_{}{}^{}\mathrm{Li}$(p,p’) cross sections differ significantly at finite values of momentum transfer (q) and do not agree with DWIA calculations. However, this discrepancy may become negligible upon extrapolation to q=0.

Nuclear states of yrast and yrare type have been investigated in pairs of valence mirror nuclei: ${}_{}{}^{110}{}_{}{}^{}\mathrm{-}_{}^{142}{}_{}{}^{}$Nd, ${}_{}{}^{114}{}_{}{}^{}\mathrm{-}_{}^{146}{}_{}{}^{}$Gd, ${}_{}{}^{43}{}_{}{}^{}\mathrm{-}_{}^{51}{}_{}{}^{}$V, ${}_{}{}^{45}{}_{}{}^{}\mathrm{-}_{}^{53}{}_{}{}^{}$Mn, as well as in some even calcium isotopes with their corresponding N=28 valence mirror isotones. The observed similarities can be related to an approximate proton-neutron symmetry in valence mirror nuclear states.

Total cross sections for proton-induced reactions on ${}_{}{}^{14,15}{}_{}{}^{}\mathrm{N}$, ${}_{}{}^{18}{}_{}{}^{}\mathrm{O}$, and ${}_{}{}^{19}{}_{}{}^{}\mathrm{F}$ targets were measured by the activation method, up to 30 MeV. Yields of nuclei of astrophysical interest, i.e., ${}_{}{}^{14,15}{}_{}{}^{}\mathrm{O}$, ${}_{}{}^{18}{}_{}{}^{}\mathrm{F}$, ${}_{}{}^{19}{}_{}{}^{}\mathrm{Ne}$ were obtained.

Resonance yields, γ-ray branching, and low-energy limits have been measured for ${}_{}{}^{18}{}_{}{}^{}\mathrm{O}$(p,γ) and ${}_{}{}^{18}{}_{}{}^{}\mathrm{O}$(α,γ), for ${\mathit{E}}_{\mathit{p}}$<0.22 MeV and ${\mathit{E}}_{\mathrm{\alpha }}$<0.78 MeV, using a 4π array of NaI detectors. The results confirm previous resonance strengths, and set additional constraints on possible low-energy contributions to stellar reaction rates.

The cross section for two-neutron removal from a beam of relativistic ${}_{}{}^{11}{}_{}{}^{}\mathrm{Li}$ is calculated in an eikonal approximation. We find a larger nuclear cross section in reactions with heavy nuclei than estimated by Kobayashi et al. This lowers the inferred Coulomb cross section for reactions on ${}_{}{}^{208}{}_{}{}^{}\mathrm{Pb}$ from 890 to a range of 560–740 mb, depending on the assumed single-particle binding energy of the valence neutron.

The origin of the $5_1^{\mathrm{-}}$ state of ${}_{}{}^{144}{}_{}{}^{}\mathrm{Nd}$ is investigated by means of the inelastic scattering of 35 MeV protons. The experimental data demonstrate that this state does not arise from the coupling of quadrupole and octupole vibrations. This results raises questions regarding the origin of low lying negative parity states in ${}_{}{}^{146}{}_{}{}^{}\mathrm{Nd}$.

There is a qualitative disagreement between the Gamow-Teller strength function extracted from the β-delayed proton decay of ${}_{}{}^{37}{}_{}{}^{}\mathrm{Ca}$ and that estimated using the ${}_{}{}^{37}{}_{}{}^{}\mathrm{Cl}$(p,n) reaction. Adelberger and Haxton have shown that this could be explained by the strong tendency of high energy states in ${}_{}{}^{37}{}_{}{}^{}\mathrm{K}$ to proton decay to ${}_{}{}^{36}{}_{}{}^{}\mathrm{Ar}$ in its first excited state. We present the results of an experiment confirming this idea. By detecting proton-γ coincidences we determined that the fraction of ${}_{}{}^{37}{}_{}{}^{}\mathrm{Ca}$ decays that feed the first excited state of ${}_{}{}^{36}{}_{}{}^{}\mathrm{Ar}$ is 2.9±0.8 %. This should be compared to a shell model prediction of 1.80±0.20 %. We also present some information on the β decay of ${}_{}{}^{25}{}_{}{}^{}\mathrm{Si}$ obtained as a by- product of our experiment.

We have measured the cross sections for charge pickup (ΔZ=+1) reactions of ${}_{}{}^{139}{}_{}{}^{}\mathrm{La}$ nuclei at three energies in the interval 390–560 MeV/nucleon in a stack of VG-13 glass detectors (〈A〉=26). Our results support evidence by Binnes et al. that the cross sections for charge pickup by heavy nuclei increase as the energy decreases below ∼600 MeV/nucleon.

Nuclear resonance fluorescence experiments have been performed on the deformed actinide nucleus ${}_{}{}^{236}{}_{}{}^{}\mathrm{U}$. Bremsstrahlung of 3.9 MeV endpoint energy has been used as the photon source. The scattered photons were detected by three high resolution Ge-γ-spectrometers installed at scattering angles of 92°, 128°, and 150°, respectively. Precise excitation energies, decay branching ratios, and ground state decay widths of numerous previously unknown spin 1 states in the excitation energy range 1.8–3.2 MeV have been extracted. The dipole strength has been found to be concentrated in the energy range 2.1–2.5 MeV. The systematics of the so-called scissors mode observed as a result of the previous (γ,γ’) and (e,e’) experiments on ${}_{}{}^{232}{}_{}{}^{}\mathrm{Th}$ and ${}_{}{}^{238}{}_{}{}^{}\mathrm{U}$ and, in particular, their combined analysis suggests likewise to attribute these new dipole excitations in ${}_{}{}^{236}{}_{}{}^{}\mathrm{U}$ to the orbital M1 scissors mode.

Hypernuclear formation through the radiative capture of in-flight ${\mathit{K}}^{\mathrm{-}}$ is studied in a distorted wave impluse approximation approach. The elementary operator is obtained from first-order Feynman diagrams and is constrained by the reactions ${\mathit{K}}^{\mathrm{-}}$p→Λγ and, via crossing, by γp→${\mathit{K}}^{+}$Λ. The ${\mathit{K}}^{\mathrm{-}}$ distortion has been included via a simple optical potential which is in agreement with ${\mathit{K}}^{\mathrm{-}}$ elastic scattering on nuclei. Using the reaction ${}_{}{}^{16}{}_{}{}^{}\mathrm{O}$(${\mathit{K}}^{\mathrm{-}}$,γ${)}_{\mathrm{\Lambda }}^{16}$N we obtain cross sections up to 10 μb for photons emitted at forward angles.

Distorted-wave impulse approximation calculations of the continuum analyzing power for the inclusive reaction ${}_{}{}^4{}_{}{}^{}\mathrm{He}$(p→,p’) at an incident energy of 100 MeV are presented. In addition to the quasifree knockout of nucleons, contributions from the knockout of deuteron, triton, and helion clusters are taken into account, together with a breakup component. Whereas nucleon knockout by itself does not account for the experimentally observed analyzing power, the inclusion of clusters has a large effect. Thus a simple knockout model is able to provide a reasonable description of the experimental continuum analyzing power.

The absorptive kaon photoproduction model of Tanabe, Kohno, and Bennhold is examined. It is found that this model predicts the wrong sign for the target polarization observable. It is further found that this problem can be remedied within the model’s original form. The model is therefore quite flexible. Comparisons are made with recent calculations.

The structures of some recently observed high-spin isomers in ${}_{}{}^{213}{}_{}{}^{}\mathrm{Rn}$ are considered. Octupole-mixed configurations are shown to account for the measured energies and electromagnetic properties of these levels.

Two truncation schemes for cranking the many-particle states of a deformed potential (including monopole pairing) are compared with some exact results. A truncation emphasizing alignment properties proves much better than a truncation which includes only the low-lying many-particle configurations at zero rotational frequency.

It is pointed out that even the new measurements relating to half-lives for $0_2^{+}$ excited states in the N=60 Zr and Mo nuclei are in line with the idea of strong-mixing between almost spherical and well deformed quadrupole shapes as the cause of large E0 matrix elements. Moreover, it is shown that similar arguments of important mixing also hold in the nuclear shell-model.