We have developed a new framework of antisymmetrized molecular dynamics (AMD), to adequately treat the $I=0\overline{K}N$ interaction, which is essential to study kaonic nuclei. The improved points are 1) ${pK}^{-}∕{n\overline{K}}^0$ mixing and 2) total spin and isospin projections. These improvements enable us to investigate various kaonic nuclei (${ppnK}^{-}$, ${pppK}^{-}$, ${pppnK}^{-}$, ${}^6\mathrm{Be}K^{-}$, ${}^9\mathrm{B}K^{-}$, and ${}^{11}\mathrm{C}K^{-}$) systematically. We have found that they are deeply bound and extremely dense with a variety of shapes.

We analyze experimental data of nuclear structure-function ratios $F_2^A∕F_2^{A^{\prime }}$ and Drell-Yan cross section ratios for obtaining optimum parton distribution functions (PDFs) in nuclei. Then, uncertainties of the nuclear PDFs are estimated by the Hessian method. Valence-quark distributions are determined by the $F_2$ data at large $x$; however, the small-$x$ part is not obvious from the data. On the other hand, the antiquark distributions are determined well at $x\sim 0.01$ from the $F_2$ data and at $x\sim 0.1$ by the Drell-Yan data; however, the large-$x$ behavior is not clear. Gluon distributions cannot be fixed by the present data and they have large uncertainties in the whole $x$ region. Parametrization results are shown in comparison with the data. We provide a useful code for calculating nuclear PDFs at given $x$ and $Q^2$.

The asymmetric nuclear matter equation of state at finite temperature is studied in the $\mathrm{SU}\left(2\right)$ chiral sigma model using mean-field approximation. The effect of temperature on effective mass, entropy, and binding energy is discussed. Treating the system to possess two conserved charges, the liquid-gas phase transition is investigated. We have also discussed the effect of the proton fraction on critical temperature with and without a $\rho$-meson contribution. We also apply our model to study the structure of the proto-neutron star with neutrino free charge-neutral matter in beta equilibrium. We found that the mass and radius of the star decreases as it cools from the entropy per baryon $S=2$ to $S=0$ and the maximum temperature of the core of the star is about $62\mathrm{MeV}$ for $S=2$.

The Faddeev-Yakubovski equations are solved in configuration space for the $\alpha$-particle and $n-{}^3\mathrm{H}$ continuum states. We test the ability of nonlocal nucleon-nucleon interaction models to describe $3N$ and $4N$ systems.

It is shown that the $\sigma \text{‐}\omega$ model which is widely used in the study of the nuclear relativistic many-body problem can be exactly treated as an Abelian massive gauge field theory. The quantization of this theory can perfectly be performed by means of the general methods described in the quantum gauge field theory. Especially, the local U(1) gauge symmetry of the theory leads to a series of Ward-Takahashi identities satisfied by Green’s functions and proper vertices. These identities form a uniquely correct basis for the renormalization of the theory. The renormalization is carried out in the mass-dependent momentum space subtraction scheme and by the renormalization group approach. With the aid of the renormalization boundary conditions, the solutions to the renormalization group equations are given in definite expressions without any ambiguity and renormalized $S$-matrix elements are exactly formulated in forms as given in a series of tree diagrams provided that the physical parameters are replaced by the running ones. As an illustration of the renormalization procedure, the one-loop renormalization is concretely carried out and the results are given in rigorous forms which are suitable in the whole energy region. The effect of the one-loop renormalization is examined by the two-nucleon elastic scattering.

Starting from HFB-6, we have constructed a new mass table, referred to as HFB-8, including all the 9200 nuclei lying between the two drip lines over the range of $Z$ and $N⩾8$ and $Z⩽120$. It differs from HFB-6 in that the wave function is projected on the exact particle number. Like HFB-6, the isoscalar effective mass $M_s^{*}$ is constrained to the value $0.80M$ and the pairing is density independent. The rms errors of the mass-data fit is $0.635\mathrm{MeV}$, i.e. better than almost all our previous HFB mass formulas. The extrapolations of this new mass formula out to the drip lines do not differ significantly from the previous HFB-6 mass formula.

New level schemes of odd-$Z$ ${}^{105,107,109}\mathrm{Tc}$ are proposed based on the ${}^{252}\mathrm{Cf}$ spontaneous-fission-gamma data taken with Gammasphere in 2000. Bands of levels are considerably extended and expanded to show rich spectroscopic information. Spin/parity and configuration assignments are made based on determinations of multipolarities of low-lying transitions and the level analogies to the previously reported levels, and to those of the neighboring $\mathrm{Rh}$ isotopes. A non-yrast negative-parity band built on the $3∕2^{-}\left[301\right]$ orbital is observed for the first time in ${}^{105}\mathrm{Tc}$. A positive-parity band built on the $1∕2^{+}\left[431\right]$ intruder orbital originating from the $\pi \left(g_{7∕2}∕d_{5∕2}\right)$ subshells and having a strong deformation-driving effect is observed for the first time in ${}^{105}\mathrm{Tc}$, and assigned in ${}^{107}\mathrm{Tc}$. A positive-parity band built on the excited $11∕2^{+}$ level, which has rather low excitation energy and predominantly decays into the $9∕2^{+}$ level of the ground state band, provides evidence of triaxiality in ${}^{107,109}\mathrm{Tc}$, and probably also in ${}^{105}\mathrm{Tc}$. Rotational constants are calculated and discussed for the $K=1∕2$ intruder bands using the Bohr-Mottelson formula. Level systematics are discussed in terms of the locations of proton Fermi levels and deformations. The band crossings of yrast positive-parity bands are observed, most likely related to $h_{11∕2}$ neutron alignment. Triaxial-rotor-plus-particle model calculations performed with $\epsilon =0.32$ and $\gamma =-22.5°$ on the prolate side of maximum triaxiality yielded the best reproduction of the excitation energies, signature splittings, and branching ratios of the positive-parity bands (except for the intruder bands) of these $\mathrm{Tc}$ isotopes. The significant discrepancies between the triaxial-rotor-plus-particle model calculations and experiment for the $K=1∕2$ intruder bands in ${}^{105,107}\mathrm{Tc}$ need further theoretical studies.

The decay of the $\left(7^{+}\right)$ and $\left({21}^{+}\right)$ isomers of the $N=\mathrm{Z}$ isotope ${}^{94}\mathrm{A}\mathrm{g}$ was studied at the GSI on-line mass separator by measuring $\beta$-delayed protons, $\gamma$ rays, proton-$\gamma$ and proton-$\gamma \text{−}\gamma$ coincidences as well as the $\beta$-strength distribution. We have observed high-spin (up to $39∕2$) states in ${}^{93}\mathrm{R}\mathrm{h}$ populated by proton emission following the $\beta$ decay of the ${}^{94}\mathrm{A}\mathrm{g}$ isomers. The major part of the population is related to the $\beta$ decay of the known $\left(7^{+}\right)$ isomer whose half-life is $0.61\left(2\right)\mathrm{s}$. The assignment of the high-spin $\left({21}^{+}\right)$ isomer in ${}^{94}\mathrm{A}\mathrm{g}$ with a half-life of $0.39\left(4\right)\mathrm{s}$ has been confirmed. The excitation energy and $\beta$-decay energy of the $\left({21}^{+}\right)$ isomer were measured to be at least 5.4 and $17.7\mathrm{MeV}$, respectively. At this excitation energy, the $\left({21}^{+}\right)$ isomer is expected to be unbound to direct one-proton, two-proton, or $\alpha$ decays. The remarkably long half-life of the $\left({21}^{+}\right)$ isomer with the highest spin and excitation energy ever observed for $\beta$-decaying nuclei makes a new textbook example of a nuclear high-spin trap. The branching ratios for $\beta$-delayed proton emission are about 20% and 27% for the decays of the $\left(7^{+}\right)$ and $\left({21}^{+}\right)$ isomers, respectively. The properties of the experimentally identified ${}^{93}\mathrm{R}\mathrm{h}$ levels are discussed in comparison to shell-model predictions.

We suggest that the transparency displayed by some light heavy-ion systems, such as ${}^{16}\mathrm{O}+{}^{16}\mathrm{O}$, ${}^{16}\mathrm{O}+{}^{12}\mathrm{C}$, or ${}^{12}\mathrm{C}+{}^{12}\mathrm{C}$, which manifests itself by the emergence of Airy structure in the elastic scattering angular distributions and excitation functions, could also have observable consequences in some inelastic channels. Indeed benchmark calculations for the $\alpha +{}^{40}\mathrm{C}\mathrm{a}$ light-ion system, where a similar mechanism dominates elastic scattering at low energy, reveals the persistence in inelastic scattering of the interference mechanism between the barrier-wave and internal-wave components of the scattering amplitude which underlies the Airy structure in the elastic channel. These calculations seem to point to new phase rules between the elastic and inelastic angular distributions.

Thermal-neutron-induced fission of ${}^{243}\mathrm{Cm}$ was studied at the Lohengrin mass separator. The light-mass peak of the fission-yield curve was investigated, and yields of masses from $A=72$ to $A=120$ were obtained. Independent-product yields were determined for nuclear charges $Z=28–37$. The yield of masses in the superasymmetric region was found to be identical to other fission reactions studied at Lohengrin. The multimodal approach to fission and the macroscopic-microscopic method for the calculation of charge-distribution parameters in isobaric chains were used to analyze experimental results from the fission of ${}^{243}\mathrm{Cm}$ and ${}^{245}\mathrm{Cm}$. A systematics on fission modes was derived from the analysis and extended to the ${}^{247}\mathrm{Cm}$ case. The weight of the ${}^{132}\mathrm{Sn}$ mode was found to decrease in ${}^{243}\mathrm{Cm}$, relative to the ${}^{245}\mathrm{Cm}$ nucleus. A prediction of the ${}^{78}\mathrm{Ni}$ yield in the fission of Cm isotopes was made. The feasibility of the study of ${}^{78}\mathrm{Ni}$ at Lohengrin has been demonstrated.

Based on the hadronic model with the gauge prescription suggested by Ohta and Haberzettl, we investigate the possibility of determining the parity state of the ${ϴ}^{+}$ baryon using photon induced processes, $\gamma n\to K^{-}{ϴ}^{+}$ and $\gamma p\to {\overline{K}}^0{ϴ}^{+}$. The total and differential cross sections are simulated in two versions of pseudovector (PV) and pseudoscalar (PS) coupling schemes and the results are reported both on the positive and negative parity states of the ${ϴ}^{+}$ baryon. It is found that in both coupling schemes the total cross sections from the neutron target are in general larger than those from the proton target, regardless of the ${ϴ}^{+}$ parity. The cross sections of the ${ϴ}^{+}$ production however depend largely on the value of the ${ϴ}^{+}$ decay width which is not yet well established. Moreover, there is a wide theoretical uncertainty associated with the different assumption on the gauge prescription in model calculations. We discuss these points by comparing theoretical predictions with the existing experimental data. Our analysis suggests that the observation of the angular distribution rather than just the total cross section in the photoproduction process may be a useful tool to distinguish the parity of the ${ϴ}^{+}$ baryon.

The onset of intruder ground states in $\mathrm{Na}$ isotopes is investigated by comparing experimental data and shell-model calculations. This onset is one of the consequences of the disappearance of the $N=20$ magic structure, and the $\mathrm{Na}$ isotopes are shown to play a special role in clarifying the change of this magic structure. Both the electromagnetic moments and the energy levels clearly indicate an onset of ground state intruder configurations at neutron number $N=19$ already, which arises only with a narrow $N=20$ shell gap in $\mathrm{Na}$ isotopes resulting from the spin-isospin dependence of the nucleon-nucleon interaction (as compared to a wider gap in stable nuclei like ${}^{40}\mathrm{Ca}$). It is shown why the previous report based on the mass led to a wrong conclusion.

An angular momentum dependence of the yrast $E2$ transition probabilities and the spectra of the low-lying states in the even-even collective nuclei are analyzed. It is shown that in the interacting boson model (IBM) it is possible to describe simultaneously the transitionlike low-lying level scheme with the rotational-like yrast $B\left(E2\right)$ values. For some values of the parameters of the general IBM-1 Hamiltonian, the values of the ratio $B\left(E2;{\left(I+2\right)}_1\to I_1\right)∕B\left(E2;2_1^{+}\to 0_1^{+}\right)$ can fall down below the rotational limit of the geometrical model and also below the prediction of the $\mathrm{SU}\left(3\right)$ limit of the IBM.

We study the occurrence of factorization in polarized and unpolarized observables in coincidence quasielastic electron scattering. Starting with the relativistic distorted wave impulse approximation, we reformulate the effective momentum approximation and show that the latter leads to observables which factorize under some specific conditions. Within this framework, the role played by final state interactions and, in particular, by the spin-orbit term is explored. Connection with the nonrelativistic formalism is studied in depth. Numerical results are presented to illustrate the analytical derivations and to quantify the differences between factorized and unfactorized approaches.

The pion decay constants of the lowest orbitally excited states of the nucleon and the $\Delta \left(1232\right)$ along with the corresponding axial transition form factors are calculated with Poincaré covariant constituent-quark models with instant, point, and front forms of relativistic kinematics. The model wave functions are chosen such that the calculated electromagnetic and axial form factors of the nucleon represent the empirical values in all three forms of kinematics, when calculated with single-constituent currents. The pion decay widths calculated with the three forms of kinematics are smaller than the empirical values. Front and instant form kinematics provide a similar description, with a slight preference for front form, while the point form values are significantly smaller in the case of the lowest positive parity resonances.

The medium modification of kaon and antikaon masses, compatible with low-energy kaon-nucleon scattering data, are studied in a chiral SU(3) model. The mutual interactions with baryons in hot hadronic matter and the effects from the baryonic Dirac sea on the $K\left(\overline{K}\right)$ masses are examined. The in-medium masses from the chiral SU(3) effective model are compared to those from chiral perturbation theory. Furthermore, the influence of these in-medium effects on kaon rapidity distributions and transverse energy spectra, as well as the $K,\overline{K}$ flow pattern in heavy-ion collision experiments at $1.5\text{–}2A\mathrm{GeV}$ are investigated within the hadron-string-dynamics transport approach. Detailed predictions on the transverse momentum and rapidity dependence of directed flow $v_1$ and the elliptic flow $v_2$ are provided for $\mathrm{Ni}+\mathrm{Ni}$ at $1.93A\mathrm{GeV}$ within the various models, that can be used to determine the in-medium $K^{\pm }$ properties from the experimental side in the near future.

The shell correction method is revisited. Contrary to the traditional Strutinsky method, the shell energy is evaluated by an averaging over the number of particles and not over the single-particle energies, which is more consistent with the definition of the macroscopic energy. In addition, the smooth background is subtracted before averaging the sum of single-particle energies, which significantly improves the plateau condition and allows one to apply the method also for nuclei close to the proton or neutron drip lines. A significant difference between the shell correction energy obtained with the traditional and the new method is found in particular for highly degenerated single-particle spectra (as, e.g., in magic nuclei) while for deformed nuclei (where the degeneracy is lifted to a large extent) both estimates are close, except in the region of super or hyper-deformed states.

The compound nucleus ${}^{76}\mathrm{Kr}*$ was populated at the excitation energy of $75\mathrm{MeV}$ and angular momentum of $39\hslash$ in fusion reactions with two complementary, mass-symmetric $({}^{31}\mathrm{P}+{}^{45}\mathrm{Sc})$ and mass-asymmetric $({}^{12}\mathrm{C}+{}^{64}\mathrm{Zn})$ entrance channels. The neutron evaporation spectra were measured and compared with the predictions of statistical model calculations using the transmission coefficients for the spherical nuclei in the inverse absorption channel, the rotating liquid drop model moment of inertia, and the normal systematic value of $A∕8$ for the level density parameter $a$. The results for the mass-asymmetric reaction are found to be consistent with the predictions of the statistical model calculations. However, for the mass-symmetric reaction $({}^{31}\mathrm{P}+{}^{45}\mathrm{Sc})$, the experimental spectra are found to be harder than the theoretical neutron spectra and the statistical model calculations require a lower value of $A∕10$ for the parameter $a$ to reproduce the shape of the experimental spectra, indicating the neutron to be evaporated at higher temperature for the same excitation energy and angular momentum in symmetric system. According to the dynamical model, the formation time $(37\times {10}^{-22}\sec )$ of the compound nucleus for the symmetric ${}^{31}\mathrm{P}+{}^{45}\mathrm{Sc}$ system is significantly higher than that $(29\times {10}^{-22}\sec )$ for the asymmetric ${}^{12}\mathrm{C}+{}^{64}\mathrm{Zn}$ system. This may probably lead to the formation of a temperature-equilibrated dinuclear complex that may be responsible for neutron emission at higher temperature in the case of the symmetric system.

The isoscalar and isovector scattering lengths $(b_0,b_1)$ are determined using a unitarized coupled channel approach based on chiral Lagrangians. Using experimental values of pionic hydrogen and deuterium as well as low energy $\pi N$ scattering data, the free parameters of the model are calculated. Isospin violation is incorporated to a certain extent by working with physical particle masses. For the deuterium scattering length $a_{{\pi }^{-}d}$ new significant corrections concerning real and imaginary parts are evaluated, putting new constraints from ${\pi }^{-}d$ scattering on the values of $(b_0,b_1)$. In particular, dispersion corrections, the influence of the $\Delta \left(1232\right)$ resonance, crossed terms and multiple scattering in a Faddeev approach are considered.