Excited states in ${}^{209}\mathrm{Fr}$ were produced following the ${}^{176}\mathrm{Yb}$(${}^{37}\mathrm{Cl}$, $4n$) reaction. An excitation function was measured with data taken at 173, 179, and 185 MeV. Recoiling fusion-evaporation products were separated using the SASSYER gas-filled spectrometer. HPGe clover detectors of the YRAST Ball array at the target position and at the focal plane were used to detect prompt and delayed gamma ray decays, providing the first spectroscopic information about prompt and delayed transitions in ${}^{209}\mathrm{Fr}$. The decay from a proposed $\pi i_{13/2}$ configuration isomer was observed in ${}^{209}\mathrm{Fr}$, and its half-life was measured to be 446(14)ns. States above the isomer were also observed.

The dynamical eikonal approximation is a quantal method unifying the semiclassical time-dependent and eikonal methods by taking into account interference effects. The principle of the calculation is described and expressions for different types of cross sections are established for two variants of the method, differing by a phase choice. The “coherent” variant respects rotational symmetry around the beam axis and is therefore prefered. A good agreement is obtained with experimental differential and integrated cross sections for the elastic breakup of the ${}^{11}\mathrm{Be}$ halo nucleus on ${}^{12}\mathrm{C}$ and ${}^{208}\mathrm{Pb}$ near 70 MeV/nucleon, without any parameter adjustment. The dynamical approximation is compared with the traditional eikonal method. Differences are analyzed and the respective merits of both methods are discussed.

Previously, the near-threshold $\mathit{pp}\to \mathit{pp}{\pi }^0$ reaction was studied with the use of transition operators derived from chiral perturbation theory (χPT) and the nuclear wave functions generated by high-precision phenomenological potentials. A conceptual problem in that approach was that the transition amplitude receives contributions from very high momentum components (above the cutoff scale of χPT) in the nuclear wave functions. In the present work, we avoid this problem by replacing the “bare” phenomenological potentials with $V_{\mathrm{low}\text{−}k}$, which is an effective potential derived from a bare potential by integrating out momentum components higher than a specified cutoff scale. The use of $V_{\mathrm{low}\text{−}k}$ is found to give an enhancement of the $\mathit{pp}\to \mathit{pp}{\pi }^0$ cross sections over the values obtained with bare potentials. Although this enhancement brings the calculated cross sections closer to the experimental values, the incident-energy dependence of the cross section is not well reproduced, a problem that seems to indicate the necessity of including higher chiral order terms than considered in the present work.

We have computed single-particle alpha and proton widths for states at 6.4–7.5 MeV in ${}^{19}\mathrm{Ne}$ and compared them with measured widths to extract spectroscopic factors. The state at 7.42 MeV appears to have either an incorrectly-assigned $J^{\pi }$ or an incorrect proton width, or both.

An important input into reaction theory is the density of states or the level density. Spectral distribution theory (also known as nuclear statistical spectroscopy) characterizes the secular behavior of the density of states through moments of the Hamiltonian. One particular approach is to partition the model space into subspaces and find the moments in those subspaces; a convenient choice of subspaces are spherical shell-model configurations. We revisit these configuration moments and find, for complete $0\hslash \omega$ many-body spaces, the following behaviors: (a) the configuration width is nearly constant for all configurations; (b) the configuration asymmetry or third moment is strongly correlated with the configuration centroid; (c) the configuration fourth moment, or excess is linearly related to the square to the configuration asymmetry. Such universal behavior may allow for more efficient modeling of the density of states in a shell-model framework.

Starting from the QCD Hamiltonian, we derive a schematic Hamiltonian for low energy quark dynamics with quarks restricted to the lowest s-level. The resulting eigenvalue problem can be solved analytically. Even though the Hamiltonian exhibits explicit chiral symmetry the severe restriction of the number of degrees of freedom breaks the pattern of chiral symmetry breaking for finite quark masses.

The reaction rates for electron capture, neutrino absorption, and neutrino scattering in hot asymmetric nuclear matter are calculated with two-body effective interactions and one-body effective weak operators obtained from realistic models of nuclear forces by use of correlated basis theory. The infinite system is modeled in a box with periodic boundary conditions, and the one-quasiparticle quasi-hole response functions are calculated with a large microcanonical sample and the Tamm-Dancoff approximation. Results for matter at a temperature of 10 MeV, proton fraction 0.4, and densities $\rho =(\frac{1}{2},1,\frac{3}{2}){\rho }_0$, where ${\rho }_0$ is the equilibrium density of symmetric nuclear matter, are presented to illustrate the method. In general, the strength of the response is shifted to higher-energy transfers when compared with that of a noninteracting Fermi gas. The shift in the response and the weakness of effective operators as compared with the bare operators significantly reduce the cross sections for electron capture and neutrino scattering by factors of $~2.5$–$3.5$. In contrast, the symmetry energy enhances the neutrino absorption reaction rate relative to the Fermi gas. However, this reaction rate is still quite small because of Pauli blocking.

Within a semiclassical nuclear Fermi-fluid dynamic approach, the properties of the isoscalar giant dipole resonance (ISGDR) and the structure of various electromagnetic characteristics associated with the most important states building this resonance are investigated. The apparent puzzling outcome of microscopic predictions that the ISGDR distribution is split into two main broad structures is confirmed within the presented macroscopic approach by the occurrence of a “low-lying” and a “high-lying” state, as the first two overtones of the same resonance. Macroscopicaly, they are pictured as a combination of compressional and vortical nuclear flows. The second part of the paper analyzes the electromagnetic structure of the ISGDR relevant to reactions with inelasticly scattered electrons and the relation between the vorticity and the toroidal dipole moment. The relative strengths of the compressional and vortical collective currents are evaluated by means of electron-scattering sum rules.

The probability distribution of the largest cluster size is studied within a three-dimensional bond percolation model on small lattices. Cumulants of the distribution exhibit distinct features near the percolation transition (pseudocritical point), providing a method for its identification. The location of the critical point in the continuous limit can be estimated without variation of the system size. This method is remarkably insensitive to finite-size effects and may be applied even for a very small system. The possibility of using various measurable quantities for sorting events makes the procedure useful in studying clusterization phenomena, in particular nuclear multifragmentation. Finite-size scaling and Δ-scaling relations are examined. The role of surface effects is evaluated by a comparison of results for free and periodic boundary conditions.

The quantitative impact of the requirement of relativistic invariance in the three-nucleon problem is examined within the framework of Poincaré invariant quantum mechanics. In the case of the bound state, and for a wide variety of model implementations and reasonable interactions, most of the quantitative effects come from kinematic factors that can easily be incorporated into a nonrelativistic momentum-space three-body code.

The nucleus ${}^{160}\mathrm{Er}$, with the structural parameter $R_{4/2}=E(4_1^{+})/E(2_1^{+})=3.10$, falls on the transition path between the critical point of the vibrator-rotor shape phase transition and the rigid rotor limit, thus serving as a critical test of the CBS rotor model, which describes this transition region. Medium-spin states of ${}^{160}\mathrm{Er}$ have been populated via the reaction ${}^{159}\mathrm{Tb}$(${}^6\mathrm{Li}$,5n) and new levels have been identified and interpreted as the even-spin members of the γ band and members of the β vibrational band. Level energies and branching ratios are compared to the CBS rotor model predictions.

The commonly used definitions of the energy and width of a single-particle resonance are cited and their differences are discussed.

We have investigated the low-energy states of ${}^{11}\mathrm{N}$ by the resonant elastic-scattering method in inverse kinematics using a ${}^{10}\mathrm{C}$ beam and a (CH${}_2){}_n$ target at the CYCLONE facility at Louvain-la-Neuve. Recoil protons were detected at laboratory angles ${\theta }_{\mathrm{lab}}=5.2^{°}\text{−}18.3^{°}$ in a $\Delta E\text{−}E$ detector system. The absolute ${}^{10}\mathrm{C}$+p elastic cross-section data were analyzed in the R-matrix framework. We found ${}^{11}\mathrm{N}$ to be unbound with respect to proton emission by $1.54\pm 0.02$ MeV, with a decay width of $0.83\pm 0.03$ MeV. These results are used to calculate the two-proton decay width of the ${}^{12}\mathrm{O}$ ground state.

Calculations of the breakup of ${}^8\mathrm{B}$ and ${}^{11}\mathrm{Be}$ are performed with the aim of analyzing their sensitivity to the projectile description. Several potentials adjusted on the same experimental data are used for each projectile. The results vary significantly with the potential choice, and this sensitivity differs from one projectile to the other. In the ${}^8\mathrm{B}$ case, the breakup cross section is approximately scaled by the asymptotic normalization coefficient (ANC) of the initial bound state. For ${}^{11}\mathrm{Be}$, the overall normalization of the breakup cross section is no longer solely determined by the ANC. The partial waves describing the continuum are found to play a significant role in this variation, as the sensitivity of the phase shifts to the projectile description changes with the physical constraints imposed to the potential.

We have used the 43 MeV/nucleon primary tritium beam of the AGOR facility with an intensity of $4\times {10}^7$ pps and the BBS experimental setup to study the (t,${}^3\mathrm{He}$) reaction between $0^{°}$ and $5^{°}$ lab angles on ${}^{12}\mathrm{C}$, ${}^{48}\mathrm{Ca}$, and ${}^{58}\mathrm{Ni}$ targets. The standard ray-tracing procedure has allowed us to obtain excitation-energy spectra up to 30 MeV in six angular bins for each residual nucleus, with an average energy resolution of 350 keV. The reaction mechanism has been described in distorted-waves Born approximation (DWBA) using the DWBA98 code. In this approximation, the form factor is treated as a folding of an effective projectile-nucleon interaction with a transition density. The effective projectile-nucleon interaction has been adjusted to reproduce the $0^{°}$ cross section of the $1^{+}$ ground state of ${}^{12}\mathrm{B}$ populated in the ${}^{12}\mathrm{C}$($t$,${}^3\mathrm{He}$) reaction. We have employed random-phase approximation (RPA) wave functions of excited states to construct the form factor instead of the normal modes wave functions used earlier. This new DWBA+RPA analysis is used to compare calculated and experimental cross sections directly and to discuss the giant resonance excitations in ${}^{48}\mathrm{K}$ and ${}^{58}\mathrm{Co}$ nuclei.

We evaluate strangeness produced in Au-Au interactions at $\sqrt{s_{\mathit{NN}}}=200$ GeV, as a function of reaction participant number A, and obtain the relative strange quark content at hadronization. Strange baryon and antibaryon rapidity density yields are studied relative to, and as function of, participant number and produced hadron yields.

We study the influence of the strong nuclear vector potential, treated using the mean-field approximation, in deep inelastic scattering. A physically consistent treatment of the electromagnetic current operator, combined with the use of the operator product expansion is presented and discussed.

The η-nucleon ($\eta N$) interactions are deduced from the heavy-baryon chiral perturbation theory to the next-to-leading-order terms. Combining the relativistic mean-field theory for nucleon system, we have studied the in-medium properties of the η meson. We find that all the elastic-scattering $\eta N$ interactions come from the next-to-leading-order terms. The $\eta N$ sigma term is found to be about 280 ± 130 MeV. The off-shell terms are also important to the in-medium properties of the η meson. On application of the latest determination of the $\eta N$ scattering length, the ratio of the η-meson effective mass to its vacuum value is near $0.84\pm 0.015$, whereas the optical potential is about $-(83\pm 5)$ MeV, at the normal nuclear density.

We calculate the property of the global color symmetry soliton with the pion field being included explicitly. The calculated results indicate that the pion field provides a strong attraction so that the eigenenergy of a quark and the mass of a soliton reduce drastically, in contrast to those with only the sigma field.

Different representations of an effective, covariant theory of the hadronic interaction are examined. For this purpose we have introduced nucleon-meson vertices parametrized in terms of scalar combinations of hadronic fields, extending the conceptual frame of the density-dependent hadronic field theory. Nuclear matter properties at zero temperature are examined in the mean-field approximation, including the equation of state, the Landau parameters, and collective modes. The treatment of isospin channels, which includes quantum chromodynamics sum-rules inputs, is outlined.