We present a simple calculation of the nucleon self-energy in nuclear matter at finite temperature in a relativistic framework, using the real-time thermal field theory. The imaginary parts of one-loop graphs are identified with discontinuities across the unitary and the Landau cuts. We find that in general both the cuts contribute significantly to the spectral function in the region of (virtual) nucleon mass usually considered, even though the unitary cut is ignored in the literature. Furthermore, our relativistic spectral function differs from the one in nonrelativistic approximation, used in some earlier calculations.

The Friedberg-Lee (FL) model is studied at finite temperature and density. The soliton solutions of the FL model in the deconfinement phase transition are solved and thoroughly discussed for certain boundary conditions. We indicate that the solitons before and after the deconfinement have different physical meanings: the soliton before deconfinement represents hadrons, while the soliton after the deconfinement represents the bound state of quarks which leads to a strongly interacting quark-gluon plasma phase. The corresponding phase diagram is given.

A variant of the basic Skyrme-Hartree-Fock functional is considered dealing with a new form of density dependence. It employs only integer powers and thus will allow a more sound basis for projection schemes (particle number, angular momentum). We optimize the new functional with exactly the same adjustment strategy as used in an earlier study with a standard Skyrme functional. This allows direct comparisons of the performance of the new functional relative to the standard one. We discuss various observables: bulk properties of finite nuclei, nuclear matter, giant resonances, superheavy elements, and energy systematics. The new functional performs at least as well as the standard one, but offers a wider range of applicability (e.g., for projection) and more flexibility in the regime of high densities.

The excitation functions for ${}^7\mathrm{Li}+{}^{28}\mathrm{Si}$ quasielastic scattering at ${150}^{°}$ and ${170}^{°}$ have been measured at sub- and near-barrier energies (0.6 to 1.3 ${\mathrm{V}}_{\mathrm{B}}$) and the corresponding barrier distributions derived. The results were analyzed within the framework of the optical model using a procedure similar to one used on previous results for ${}^6\mathrm{Li}+{}^{28}\mathrm{Si}$ employing double-folded potentials calculated using the BDM3Y1 effective interaction. The variation of the surface strength of the optical potential as a function of incident energy was compared for the two systems ${}^6\mathrm{Li}+{}^{28}\mathrm{Si}$ and ${}^7\mathrm{Li}+{}^{28}\mathrm{Si}$, the barrier distributions being used to help better define the potential at the lowest energies. The barrier distributions were also analyzed with continuum-discretized coupled-channel (CDCC) and coupled reaction channel (CRC) calculations as a means of investigating the influence of breakup and transfer reactions on these quantities for these light, weakly bound projectiles.

The total reaction cross section ${\sigma }_{\mathrm{reac}}$ is a valuable measure for the prediction of $\alpha$-induced reaction cross sections within the statistical model and for the comparison of scattering of tightly bound projectiles to weakly bound and exotic projectiles. Here we provide the total reaction cross sections ${\sigma }_{\mathrm{reac}}$ derived from our previously published angular distributions of elastic $\alpha$-nucleus scattering on ${}^{89}\mathrm{Y}$, ${}^{92}\mathrm{Mo}$, ${}^{112,124}\mathrm{Sn}$, and ${}^{144}\mathrm{Sm}$ at energies around the Coulomb barrier.

Cross sections of ${}^{120}\mathrm{Sn}$($\alpha$,$\alpha$)${}^{120}\mathrm{Sn}$ elastic scattering have been extracted from the $\alpha$-particle-beam contamination of a recent ${}^{120}\mathrm{Sn}$(${}^6\mathrm{He}$,${}^6\mathrm{He}$)${}^{120}\mathrm{Sn}$ experiment. Both reactions are analyzed using systematic double-folding potentials in the real part and smoothly varying Woods-Saxon potentials in the imaginary part. The potential extracted from the ${}^{120}\mathrm{Sn}$(${}^6\mathrm{He}$,${}^6\mathrm{He}$)${}^{120}\mathrm{Sn}$ data may be used as the basis for the construction of a simple global ${}^6\mathrm{He}$ optical potential. The comparison of the ${}^6\mathrm{He}$ and $\alpha$ data shows that the halo nature of the ${}^6\mathrm{He}$ nucleus leads to a clear signature in the reflexion coefficients ${\eta }_L$: The relevant angular momenta $L$ with ${\eta }_L\gg 0$ and ${\eta }_L\ll 1$ are shifted to larger $L$ with a broader distribution. This signature is not present in the $\alpha$-scattering data and can thus be used as a new criterion for the definition of a halo nucleus.

The symmetry energy coefficients of dilute clusterized nuclear matter are evaluated in the $S$-matrix framework. Employing a few different definitions commonly used in the literature for uniform nuclear matter, it is seen that the different definitions lead to perceptibly different results for the symmetry coefficients for dilute nuclear matter. They are found to be higher compared to those obtained for uniform matter in the low density domain. The calculated results are in reasonable consonance with those extracted recently from experimental data.

Level structures in ${}^{60,62}\mathrm{Fe}{}_{34,36}$ and adjacent nuclei were studied with Gammasphere using the reaction of a $430$-MeV ${}^{64}\mathrm{Ni}$ beam on a 55-mg/cm${}^2$ thick ${}^{238}\mathrm{U}$ target. High-spin level schemes were deduced from singly- and doubly-gated prompt coincidence events. Levels populated in the $\beta$ decay of ${}^{60,62}\mathrm{Mn}$ isomers were studied in singly- and doubly-gated delayed coincidences. Spin and parity assignments were deduced from angular correlations of $\gamma$ rays observed in both nuclei, leading to firm positive-parity yrast assignments up through $8^{+}$ in ${}^{62}\mathrm{Fe}$. The observed levels for ${}^{60}\mathrm{Fe}$ up to $~3.5$ MeV compare well with $\mathit{pf}$ shell-model calculations available in the literature. Calculations performed in a limited $\mathit{pfg}$ basis exhibit reasonable agreement for the $2^{+}$, $4^{+}$, and $6^{+}$ levels in ${}^{62}\mathrm{Fe}$. However, theoretical descriptions that include the newly identified negative-parity levels in ${}^{62}\mathrm{Fe}$ require a much larger basis, necessarily including $g_{9/2}$ neutrons, as well as improved interactions leading to negative-parity levels.

The high-spin level structures of the ${}^{96,97}\mathrm{Nb}$ isotopes have been studied. The isotopes were produced in the fission of the compound systems formed in two heavy-ion-induced reactions, ${}^{24}\mathrm{Mg}$ (134.5 MeV) $+$ ${}^{173}\mathrm{Yb}$ and ${}^{23}\mathrm{Na}$ (129 MeV) $+$ ${}^{176}\mathrm{Yb}$. Gamma-ray spectroscopy was accomplished with the Gammasphere array. High-spin states are observed for the first time in both isotopes with excitation energies up to 5.2 and 6.6 MeV in ${}^{96,97}\mathrm{Nb}$, respectively. The coupling of the odd proton occupying the $g_{9/2}$ orbital to the yrast states in the subshell closure nucleus of ${}^{96}\mathrm{Zr}$ can account for the first excited states of ${}^{97}\mathrm{Nb}$. A comparison with the first excited states in ${}^{95}\mathrm{Zr}$ is also attempted. The addition of a neutron hole in ${}^{96}\mathrm{Nb}$ results in a much more fragmented level scheme.

Fragment mass distributions for fission after full momentum transfer were measured for the ${}^{30}\mathrm{Si}$$+$${}^{238}\mathrm{U}$ reaction at bombarding energies around the Coulomb barrier. At energies above the Bass barrier, the mass distributions were Gaussian with mass symmetry. An asymmetric fission channel with mass $A_{\mathrm{L}}/A_{\mathrm{H}}$ $\approx$ $90/178$ emerged at the sub-barrier energies, where competition between fusion and quasifission was suggested from the evaporation residue (ER) cross section produced in the fusion ${}^{30}\mathrm{Si}$$+$${}^{238}\mathrm{U}$. We thus conclude the asymmetric channel is attributed to quasifission. It was supported by a model calculation using the Langevin equation to give the fragment mass distribution, where fusion-fission and quasifission were separated. The observed mass asymmetry for quasifission as well as the calculation is significantly smaller than those observed in actinide targets bombarded with heavier projectiles, which suggests that the system ${}^{30}\mathrm{Si}$$+$${}^{238}\mathrm{U}$ approaches the shape of the compound nucleus before disintegrating as quasifission.

The inelastic cross section of deuterons hitting a lead target has been determined by the beam attenuation technique. A spallation neutron source based on a lead target was irradiated with 1.6- and 2.5-GeV deuterons. Solid-state nuclear track detectors as well as the activation method were used to obtain the neutron and proton distribution along the surface of the source. The attenuation coefficient was estimated by fitting the experimental data and taking into account the buildup effect and the beam attenuation. Using the attenuation coefficient, the interaction length and then the inelastic cross section of deuterons on lead reaction were determined.

Reflection asymmetric relativistic mean-field theory is used to investigate the shape evolution for even-even Th isotopes. The calculated deformations, matter density distributions, and potential energy surfaces demonstrate clearly the shape evolution from spherical to octupole deformed. Especially, it is shown that Th isotopes suffer two types of shape transition when the neutron number increases from $N=126$ to $N=156$. One is from spherical to octupole deformed around $N=134$, and another is from octupole to quadrupole deformed around $N=150$.

The neutron-deficient nucleus ${}^{199}\mathrm{At}$ has been studied through $\gamma$-ray and electron spectroscopy, using the recoil-decay tagging technique. Two experiments were conducted, using a gas-filled recoil separator with a focal-plane spectrometer alone and together with a germanium-detector array at the target position. The resulting level scheme for ${}^{199}\mathrm{At}$ includes a new isomer with a half-life of 0.80(5) $\mu$s and a spin and parity of ($29/2^{+}$). The $13/2^{+}$ isomer, which de-excites via an $M2$ transition to the $9/2^{-}$ ground state, was measured to have a half-life of 70(20) ns. Our earlier version of the level scheme for ${}^{197}\mathrm{At}$ has been updated as well.

Relativistic mean-field theory allowing for triaxial deformations is applied for a systematic study of fission barriers in the actinide region. Different pairing schemes are studied in detail and it is shown that covariant density functional theory is able to describe fission barriers on a level of accuracy comparable with nonrelativistic calculations, even with the best phenomenological macroscopic$+$microscopic approaches. Triaxiality in the region of the first saddle plays a crucial role in achieving that.

The macroscopic-microscopic mass formula is further improved by considering mirror nuclei constraint. The rms deviation with respect to 2149 measured nuclear masses is reduced to $0.441$ MeV. The shell corrections, the deformations of nuclei, the neutron and proton drip lines, and the shell gaps are also investigated to test the model. The rms deviation of $\alpha$-decay energies of 46 superheavy nuclei is reduced to $0.263$ MeV. The predicted central position of the superheavy island could lie around $N=176~178$ and $Z=116~120$ according to the shell corrections of nuclei.

Rotational bands have been identified up to high spins ($\approx$$28\hslash$) in the odd-$A$ nuclei ${}^{247,249}\mathrm{Cm}$ and ${}^{249}\mathrm{Cf}$ through inelastic excitation and transfer reactions around the $Z=100$ region where stability results from shell effects. The [620]1/2 Nilsson configuration in ${}^{249}\mathrm{Cm}$ is the highest-lying neutron orbital, from above the $N=164$ spherical subshell gap, for which high-spin rotational behavior has been established. The data allow for an unambiguous experimental assignment of configurations to the observed bands, unusual for odd-$A$ nuclei near $Z=100$. The high-spin properties are described in terms of Woods-Saxon cranking calculations.

Two-particle two-hole contributions to electromagnetic response functions are computed in a fully relativistic Fermi gas model. All one-pion exchange diagrams that contribute to the scattering amplitude in perturbation theory are considered, including terms for pionic correlations and meson-exchange currents (MECs). The pionic correlation terms diverge in an infinite system and thus are regularized by modification of the nucleon propagator in the medium to take into account the finite size of the nucleus. The pionic correlation contributions are found to be of the same order of magnitude as the MECs.

Within an isospin- and momentum-dependent hadronic transport model, we have investigated the isospin mixing with the probe of the ${\pi }^{-}/{\pi }^{+}$ ratio in central isospin asymmetric ${}^{96}\mathrm{Ru}+{}^{96}\mathrm{Zr}$ collision at an incident energy of 400 MeV/u. The isospin equilibrium is not reached according to the asymmetrical distribution of the ${\pi }^{-}/{\pi }^{+}$ ratio with rapidity. In comparison with the nucleon observable, it suggests that the pion ratio ${\pi }^{-}/{\pi }^{+}$ is a promising observable to probe the relaxation of isospin degree of freedom in central heavy ion collisions without being strongly affected by the surface effect. Because of the small system size and rather strong effect of rescattering on pions, the isospin mixing shows insignificant dependence on the stiffness of the symmetry energy in the relevant colliding system.

The process of complex fragment emission is studied within the dinuclear system model. Cross sections of complex fragment emission are calculated and compared with experimental data for the reactions ${}^3\mathrm{He}+{}^{\mathrm{nat}}\mathrm{Ag}$, ${}^{78,86}\mathrm{Kr}+{}^{12}\mathrm{C}$, and ${}^{63}\mathrm{Cu}+{}^{12}\mathrm{C}$. The mass distributions of the products of these reactions, isotopic distributions for the ${}^3\mathrm{He}+{}^{\mathrm{nat}}\mathrm{Ag}$ and ${}^{78}\mathrm{Kr}+{}^{12}\mathrm{C}$ reactions, and average total kinetic energies of the products of the ${}^{78}\mathrm{Kr}+{}^{12}\mathrm{C}$ reaction are predicted.

The half-life of ${}^{38}\mathrm{K}$${}^m$ has been measured to be 924.46(14) ms, a result that is a factor of two more precise than any of the five previous measurements of this quantity. The previous results are not consistent with one another, but our result agrees well with the two most recent ones. The derived $\mathit{ft}$ value for ${}^{38}\mathrm{K}$${}^m$ is now one of the three most precisely known superallowed $\mathit{ft}$ values.