The width of the 0.55-MeV ${}_{}{}^{13}{}_{}{}^{}\mathrm{C}$(p,γ) resonance is found to be 37.3±0.5 keV, in serious disagreement with a recent measurement. The proton energies of the two lowest resonances in ${}_{}{}^{13}{}_{}{}^{}\mathrm{C}$(p,γ) are found to be 448.3±0.5 and 553.3±0.6 keV, in agreement with previous findings.

The inelastic scattering of 35 MeV protons has been used to excite seven states below 2.1 MeV in ${}_{}{}^{146}{}_{}{}^{}\mathrm{Nd}$. A comparison between a coupled-channels calculation that assumes an octupole coupled structure for the $5^{\mathrm{-}}$ state at 1.517 MeV and the observed cross section suggests that the wave function of this state includes only a small two-quasiparticle component. In addition, the present results indicate that the level at 2.073 MeV, previously assigned ${\mathit{J}}^{\mathrm{\pi }}$=$4^{\mathrm{-}}$, actually has ${\mathit{J}}^{\mathrm{\pi }}$=$3^{\mathrm{-}}$.

We used nuclear track detectors to construct the trajectories of interactions and to measure with high resolution the charge of the beam and of heavy nuclear fragments produced in interactions. A null result of our search for fractional charge states in high-energy fragments with charges 8≤Z≤13 produced in collisions of 14.5A GeV ${}_{}{}^{28}{}_{}{}^{}\mathrm{Si}$ nuclei with Pb and Cu targets leads us to conclude that the upper limits for the probability of production of a fragment with charge 23/3, 25/3, 26/3 28/3 29/3, 31/3 32/3, 34/3, 35/3, 37/3, or 38/3 charge unit in Pb and Cu at 90% confidence level are 1.9×${10}^{\mathrm{-}4}$ and 3.9×${10}^{\mathrm{-}4}$, respectively. We set a similar limit on the relative number of particle-stable fragments with 8≤Z≤14 created in the central rapidity region.

We have measured the ${}_{}{}^{35}{}_{}{}^{}\mathrm{Cl}$(n,p${)}^{35}$S cross section from 25 meV to 100 keV. Strengths were determined for the resonances at ${\mathit{E}}_{\mathit{n}}$=398, 4249, 16340, 27316, and 57700 eV. The proton width for the ${\mathit{J}}^{\mathrm{\pi }}$=$2^{+}$ state just below threshold was calculated using previously known resonance parameters and the thermal cross section. The cross section calculated from the parameters for this state was found to be in good agreement with our data to approximately 100 eV. The astrophysical reaction rate, ${\mathit{N}}_{\mathit{A}}$〈σv〉, was calculated from the resonance strengths determined in our measurements, plus the thermal cross section. The role of this reaction in the nucleosynthesis of light elements in the s process as well as in explosive nucleosynthesis is discussed.

Electron scattering from ${}_{}{}^{13}{}_{}{}^{}\mathrm{C}$ was measured at a momentum transfer of 5.08 ${\mathrm{fm}}^{\mathrm{-}1}$. No electron events were observed in the vicinity of the elastic peak, giving an upper limit for the elastic cross section of 1.2×${10}^{\mathrm{-}39}$ ${\mathrm{cm}}^2$/sr with a confidence level of 90%. At this momentum transfer, the square of the elastic M1 form factor apparently continues to fall exponentially with q. Comparison of the data with shell-model calculations indicates that admixtures of 2ħω configurations in the ${}_{}{}^{13}{}_{}{}^{}\mathrm{C}$ ground state cannot entirely explain the high-q enhancement of the M1 form factor relative to 1p-shell calculations.

Experimental fissility data from photofission reactions of ${}_{}{}^{232}{}_{}{}^{}\mathrm{Th}$, ${}_{}{}^{238}{}_{}{}^{}\mathrm{U}$, and ${}_{}{}^{235}{}_{}{}^{}\mathrm{U}$ nuclei at 52 MeV have been obtained using monochromatic and polarized photon beams and dielectric fission-track detectors. These data, along with literature data for ${}_{}{}^{237}{}_{}{}^{}\mathrm{Np}$, ${}_{}{}^{235,238}{}_{}{}^{}\mathrm{U}$, ${}_{}{}^{232}{}_{}{}^{}\mathrm{Th}$, ${}_{}{}^{209}{}_{}{}^{}\mathrm{Bi}$, ${}_{}{}^{208}{}_{}{}^{}\mathrm{Pb}$, and ${}_{}{}^{174}{}_{}{}^{}\mathrm{Yb}$ nuclei have been analyzed within the framework of a simple two-step model for photofission reactions, i.e., absorption of the incident photon by a neutron-proton pair followed by an evaporation-fission competition mechanism for the excited nucleus. For nuclei in the Ta-Np region the trend of calculated fissilities clearly shows shell effects in the vicinity of ${}_{}{}^{208}{}_{}{}^{}\mathrm{Pb}$. In the case of ${}_{}{}^{238}{}_{}{}^{}\mathrm{U}$ the effect of photon polarization on fission direction has also been studied, and isotropy was observed in the fragment azimuthal distribution.

We have measured the cross section for nuclear charge pickup by relativistic holmium on several targets of larger atomic number than have been studied previously. We find that although measurements made with most of the targets are consistent with a peripheral geometric scaling, one target, silver, shows an anomalously high cross section.

Angular distributions of the analyzing powers have been measured for the ${}_{}{}^3{}_{}{}^{}\mathrm{He}$(p→,${\mathrm{\pi }}^{+}$${)}^4$He reaction at proton bombarding energies of 300, 416, and 507 MeV. These results, together with existing measurements at 178, 198, and 800 MeV, provide a comprehensive set of data spanning the region of the ${\mathrm{\Delta }}_{1232}$ resonance. The results are compared with a phenomenological model that incorporates the amplitudes for the pp→d${\mathrm{\pi }}^{+}$ reaction and calculations from a microscopic (p,${\mathrm{\pi }}^{+}$) model.

Double cross sections in p+α and ${}_{}{}^3{}_{}{}^{}\mathrm{He}$+α bremsstrahlung are calculated with a simple procedure in which the antisymmetrization of the wave function is not explicitly taken into account, but approximately compensated for by using a renormalized wave function obtained by operating with the square root of the norm operator on the relative-motion function of the resonating-group method (RGM). A comparison with the RGM results show that the approximation works reasonably well and can be used to systematically investigate the features of bremsstrahlung in many nuclear systems, for the purpose of learning about the off-the-energy-shell behavior of the intercluster interaction.

The strong coupling between the real and imaginary terms in the optical potential for ${}_{}{}^{16}{}_{}{}^{}\mathrm{O}$${+}^{60}$Ni, ${}_{}{}^{208}{}_{}{}^{}\mathrm{Pb}$ previously reported for elastic scattering at bombarding energies close to the Coulomb barrier does not occur for the elastic scattering of ${}_{}{}^6{}_{}{}^{}\mathrm{Li}$${+}^{28}$Si. This result confirms the suggestion of Mahaux, Ngô, and Satchler that the dispersion relation connecting the real and imaginary potential terms found for ${}_{}{}^{16}{}_{}{}^{}\mathrm{O}$ scattering will not occur for weakly bound projectiles.

The structure of the ${}_{}{}^{104}{}_{}{}^{}\mathrm{In}$ nucleus was studied by means of interacting boson-fermion-fermion model. All the experimentally known states below 1.2 MeV were assigned to proton-neutron multiplets on the basis of their electromagnetic properties. A W-like energy splitting of the π${\mathit{g}}_{9/2}^{\mathrm{-}1}$νd${\mathrm{̃}}_{5/2}$ and a slightly distorted, open-up parabolic splitting of the π${\mathit{g}}_{9/2}^{\mathrm{-}1}$νg${\mathrm{̃}}_{7/2}$ multiplet have been predicted by the model, in agreement with the experiment.

The Coulomb sum rule is evaluated for a large class of nuclei up to the heavy ones. Beyond mean-field effects, short-range correlations are taken into account. The latter decrease the sum rule in the whole considered momentum range. The size of the reduction increases with the average proton density reaching its maximum for medium heavy nuclei.

The energy levels of the muonic hydrogen atom are calculated using proton charge distribution due to the nonrelativistic quark model. The charge form factor of the proton calculated in the model is in reasonable agreement with electron-scattering measurements. The effect of two orders of vacuum polarization and the finite size of the proton is included. We find good agreement with the results of earlier works, especially where the experimental charge distribution of the proton was employed. This calculation provides a useful test of nonrelativistic quark models.

The effect of one- and two-body dissipation on the damping of giant dipole resonances (GDR’s) is studied in a semiclassical approach solving a Vlasov equation with a collision relaxation time. The latter is microscopically evaluated from the equilibration of a distorted momentum distribution in a kinetic approach. Temperature effects are introduced in the initial distribution function and in Pauli blocking rearrangement in the path to equilibration. Particle emission is also computed in the same microscopic picture. Without free parameters a good agreement with data is obtained for GDR’s on the ground state. For collective vibration built on excited states we get a dramatic increase of the widths due to the enhancement of nucleon-nucleon (NN) collisions. The saturation observed in some experiments is explained as due to the competition of particle evaporation which cools down the system. The transition to first-sound modes is ruled out for the persistence of long-nucleon mean free paths at relatively high temperatures.

Measurements using 200 MeV protons of the spin-flip probability parameter ${\mathrm{S}}_{\mathrm{NN}\prime }$ have been made on ${\mathrm{Pb}}^{208}$ covering an excitation energy range of 2 to 24 MeV for momentum transfers from 0.45 to 0.84 ${\mathrm{fm}}^{-1\mathrm{}}$. These data have been compared to calculations that use random-phase-approximation wave functions in an impulse approximation model. Distortions are shown to have a large effect in the calculation of ${\mathrm{S}}_{\mathrm{NN}\prime }$. The calculations describe the data well and suggest that natural-parity transitions contribute significantly to the spin-flip response. A broad structure is observed near 7 MeV; calculations suggest that this structure is composed of a superposition of a number of spins and parities.

Two-neutron correlations at small relative momentum in ${}_{}{}^{20}{}_{}{}^{}\mathrm{Ne}$+C and ${}_{}{}^{20}{}_{}{}^{}\mathrm{Ne}$+Co reactions at 30A MeV exhibit correlation functions dominated by the attractive final-state interaction. The results are consistent with two-proton data. The data suggest large apparent emission sources for both reactions with contributions from both pre-equilibrium emission and evaporation.

Inclusive cross sections of intermediate mass fragments from the reaction ${}_{}{}^{40}{}_{}{}^{}\mathrm{Ar}$${+}^{197}$Au at E/A=30 and 220 MeV were measured with a low threshold and over a large range of angles. The integrated cross sections are about 2 b at both energies but the emission characteristics change considerably. The increased isotropy of the angular distributions and the strongly reduced Coulomb repulsion at the higher bombarding energy suggest that the emission process evolves towards fragmentation of excited spectator matter in central ion-ion collisions.

Excited states in the very neutron-deficient nucleus ${}_{}{}^{174}{}_{}{}^{}\mathrm{Pt}$ have been identified up to spin 14. An irregular yrast sequence was observed beginning with a high $2^{+}$→$0^{+}$ energy. It can be interpreted as the result of a change from a weakly deformed ground-state band, to a well-deformed rotor, near spin 6.