High precision excitation functions of large-angle quasi-elastic scattering for the systems of ${}^{16}\mathrm{O}+{}^{208}\mathrm{Pb}$, ${}^{196}\mathrm{Pt}$, ${}^{184}\mathrm{W}$, and ${}^{154,152}\mathrm{Sm}$ at energies well below the Coulomb barrier were measured. The surface diffuseness parameters of the real part of the Woods-Saxon potential have been extracted from the single-channel and coupled-channels calculations, respectively. By considering the effect of couplings, the extracted diffuseness parameters are in the range from 0.64 to 0.69 fm, which is close to the values extracted from the systematic analyses of elastic and inelastic scattering data. On the other hand, single-channel calculations give somewhat larger values in the range from 0.68 to 0.77 fm, especially for systems with deformed target nuclei.

In heavy-ion collisions, isoscaling provides a method for studying the evolution of nuclear symmetry energy as a function of excitation energy. One challenge in using isoscaling is to accurately determine the neutron-to-proton ratio ($N/Z$) of the fragmenting source. Isoscaling results are presented for the reactions of ${}^{86,78}\mathrm{Kr}+{}^{64,58}\mathrm{Ni}$ at 35 MeV/nucleon taken on the NIMROD-ISiS array at Texas A&M University. The $N/Z$ of the source was calculated from the isotopically identified fragments and experimentally measured neutrons emitted from reconstructed quasiprojectiles. These data exhibit isoscaling for elements with $Z=1\text{−}17$ over a broad range of isotopes. The isoscaling parameter $\alpha$ is shown to increase with increasing difference in the neutron composition (Δ) of the compared sources. For a selected Δ, the ratio $\alpha$/Δ is also shown to decrease with increasing excitation energy. This may reflect a corresponding decrease in the nuclear symmetry energy.

The $\gamma$ decay associated with the warm rotation of the superdeformed nuclei ${}^{151}\mathrm{Tb}$ and ${}^{196}\mathrm{Pb}$ has been measured with the Euroball IV array. Several experimental quantities are presented, putting strong constraints on the decay dynamics in the superdeformed well. The data are successfully reproduced using a Monte Carlo simulation of the $\gamma$ decay based on microscopically calculated energy levels, $E2$ decay probabilities, collective mass parameters, and potential energy barriers between the wells associated with normal and super deformation. This allows one to test the basic ingredients of the physical process, such as the strength of the two-body residual interaction and the potential barriers as a function of spin and excitation energy. We also show that the data probe the $E1$ strength function, indicating an enhancement around 1–2 MeV $\gamma$ rays, which might be related to octupole vibrations.

A Monte Carlo simulation of the $\gamma$ decay of superdeformed nuclei has been developed. It is based on microscopic calculations for the energy levels, $E2$ decay probabilities, collective mass parameters, and potential energy barriers. The use of microscopically calculated quantities largely reduces the parameters of the simulation, allowing one to focus on the basic ingredients of the physical processes. Calculations are performed for the warm rotating superdeformed nuclei ${}^{151}\mathrm{Tb}$ and ${}^{196}\mathrm{Pb}$, for which high statistics Euroball IV data are available. The dependence on the simulation parameters is investigated, together with the basic features of the microscopic calculations.

The short-range and tensor components of the bare nucleon-nucleon interaction induce a sizable depletion of low momenta in the ground state of a nuclear many-body system. The self-consistent Green's function method within the ladder approximation provides an ab initio description of correlated nuclear systems that accounts properly for these effects. The momentum distribution predicted by this approach is analyzed in detail, with emphasis on the depletion of the lowest momentum state. The temperature, density, and nucleon asymmetry (isospin) dependence of the depletion of the Fermi sea is clarified. A connection is established between the momentum distribution and the time-ordered components of the self-energy, which allows for an improved interpretation of the results. The dependence on the underlying nucleon-nucleon interaction provides quantitative estimates of the importance of short-range and tensor correlations in nuclear systems.

Excited states of the nucleus ${}^{167}\mathrm{Os}$ have been populated by the reaction ${}^{92}\mathrm{Mo}({}^{78}\mathrm{Kr},2\mathit{pn})$. The JUROGAM $\gamma$-ray detector array has been used in conjunction with the RITU gas-filled separator and the GREAT spectrometer to observe prompt $\gamma$ rays in coincidence with recoiling fusion-evaporation residues and their subsequent decay by $\alpha$ particle emission. By correlating prompt $\gamma$ radiation with the characteristic $\alpha$ radioactivity of ${}^{167}\mathrm{Os}$, it has been possible to extend the level scheme for this nucleus significantly. In particular, an extension of the yrast band and four previously unobserved bands are reported. In addition, the recoil distance Doppler-shift method was used to determine a lifetime of $\tau =20(4)$ ps for The $I^{\pi }=17/2^{+}$ state in ${}^{167}\mathrm{Os}$. Hence, the level of collectivity and magnitude of deformation of the low spin yrast band of this nucleus is established.

We calculate the low-lying spectra and several high-spin states of zirconium isotopes ($Z=40$) with neutron numbers from $N=50$ to $N=58$ using a large valence space with the ${}^{78}\mathrm{Ni}$ inert core, which a priori allows one to study the interplay between spherical and deformed configurations, necessary for the description of nuclides in this part of the nuclear chart. The effective interaction is derived by monopole corrections of the realistic $G$ matrix. We reproduce essential nuclear properties, such as subshell closures in ${}^{96}\mathrm{Zr}$ and ${}^{98}\mathrm{Zr}$. The spherical-to-deformed shape transition in ${}^{100}\mathrm{Zr}$ is addressed as well.

A new approach based on the wave-packet continuum discretization method recently developed by the present authors for solving quantum-mechanical scattering problems for atomic and nuclear scattering processes and few-body physics is described. The formalism uses the complete continuum discretization scheme in terms of the momentum stationary wave-packet basis, which leads to formulation of the scattering problem on a lattice in the momentum space. The solution of the few-body scattering problem can be found in the approach from linear matrix equations with nonsingular matrix elements, averaged on energy over lattice cells. The developed approach is illustrated by the solution of numerous two- and three-body scattering problems with local and nonlocal potentials below and well above the three-body breakup threshold.

A microscopic helium-3 optical potential is obtained by Green function method through nuclear matter approximation and local density approximation based on the effective Skyrme interaction. The reaction cross sections and the elastic scattering angular distributions are calculated by the microscopic optical potential for nuclides in the mass range $12⩽A⩽208$ with incident helium-3 energies from threshold up to 200 MeV. The results of theoretical calculations are compared with the experimental data.

We determine the $u$ and $d$ quark contributions to the proton magnetic form factor at finite momentum transfer by applying chiral corrections to quenched lattice data. Heavy baryon chiral perturbation theory is applied at next-to-leading order in the quenched and full QCD cases for the valence sector using finite range regularization. Under the assumption of charge symmetry these values can be combined with the experimental values of the proton and neutron magnetic form factors to deduce a relatively accurate value for the strange magnetic form factor at $Q^2=0.23\hspace{0.5em}{\mathrm{GeV}}^2$, namely, $G_M^s=-0.034\pm 0.021\hspace{0.5em}{\mu }_N$.

The configuration-fixed constrained triaxial relativistic mean-field approach is extended by including time-odd fields and applied to the study of the candidate multiple chiral doublets (MχD) nucleus ${}^{106}\mathrm{Rh}$. The energy contribution from time-odd fields and microscopical evaluation of center-of-mass correction as well as the modification of triaxial deformation parameters $\beta ,\gamma$ due to the time-odd fields are investigated. The contributions of the time-odd fields to the total energy are 0.1–0.3 MeV, and they modify slightly the $\beta ,\gamma$ values. However, the previously predicted multiple chiral doublets still exist.

The nuclear magnetic moment of the ground state of ${}^{55}\mathrm{Ni}$ ($I^{\pi }=3/2^{-}$, $T_{1/2}=204$ ms) has been deduced to be $|\mu ({}^{55}\mathrm{Ni})|=(0.976\pm 0.026)\hspace{0.5em}{\mu }_N$ using the $\beta$-ray detecting nuclear magnetic resonance technique. Results of a shell model calculation in the full $\mathit{fp}$ shell model space with the GXPF1 interaction reproduce the experimental value. Together with the known magnetic moment of the mirror partner ${}^{55}\mathrm{Co}$, the isoscalar spin expectation value was extracted as $\langle \sum {\sigma }_z\rangle =0.91\pm 0.07$. The $\langle \sum {\sigma }_z\rangle$ shows a trend similar to that established in the $\mathit{sd}$ shell. The present theoretical interpretations of both $\mu ({}^{55}\mathrm{Ni})$ and $\langle \sum {\sigma }_z\rangle$ for the $T=1/2$, $A=55$ mirror partners support the softness of the ${}^{56}\mathrm{Ni}$ core.

We argue that measurements of identified-particle elliptic flow in a wide energy range could shed light on the possible phase change in high-energy heavy ion collisions at the BNL Relativistic Heavy Ion Collider (RHIC). When the hadronization process is dominated by quark coalescence, the number-of-constituent-quark (NCQ) scaling for the identified-particle elliptic flow can serve as a probe for studying the strong interacting partonic matter. In the upcoming RHIC low-energy runs, the NCQ scaling behavior may be broken because of the change of the effective degrees of freedom of the hot dense matter, which corresponds to the transition from the dominant partonic phase to the dominant hadronic phase. A multiphase transport model is used to present the dependence of NCQ scaling behavior on the different hadronization mechanisms.

A new upper limit of $2.3\times {10}^{-4}$ on the branching ratio of the decay $\omega \to \eta {\pi }^0$ has been obtained using the Crystal Ball multiphoton spectrometer at the Mainz Microtron MAMI. This decay is forbidden by charge-conjugation invariance of the strong and electromagnetic interactions. We have also obtained the upper limit of $2.3\times {10}^{-4}$ for the forbidden decay $\omega \to 3{\pi }^0$ and the upper limit of $2.4\times {10}^{-4}$ for $\omega \to 2{\pi }^0$.

A new rotational band has been identified in ${}^{103}\mathrm{Zr}$ with a proposed $3/2^{+}$ band head located at 26.8 keV. Quasiparticle rotor model calculations performed in the present work suggest a $\nu 3/2^{+}$ [411] dominant configuration for this band. The calculations also indicate that ${}^{103}\mathrm{Zr}$ has axial prolate deformation.

We present calculations of fission properties for heavy elements. The calculations are based on the macroscopic-microscopic finite-range liquid-drop model with a 2002 parameter set. For each nucleus we have calculated the potential energy in three different shape parametrizations: (1) for 5 009 325 different shapes in a five-dimensional deformation space given by the three-quadratic-surface parametrization, (2) for 10 850 different shapes in a three-dimensional deformation space spanned by ${\epsilon }_2$, ${\epsilon }_4$, and $\gamma$ in the Nilsson perturbed-spheroid parametrization, supplemented by a densely spaced grid in ${\epsilon }_2$, ${\epsilon }_3$, ${\epsilon }_4$, and ${\epsilon }_6$ for axially symmetric deformations in the neighborhood of the ground state, and (3) an axially symmetric multipole expansion of the shape of the nuclear surface using ${\beta }_2$, ${\beta }_3$, ${\beta }_4$, and ${\beta }_6$ for intermediate deformations. For a fissioning system, it is always possible to define uniquely one saddle or fission threshold on the optimum trajectory between the ground state and separated fission fragments. We present such calculated barrier heights for 1585 nuclei from $Z=78$ to $Z=125$. Traditionally, actinide barriers have been characterized in terms of a “double-humped” structure. Following this custom we present calculated energies of the first peak, second minimum, and second peak in the barrier for 135 actinide nuclei from Th to Es. However, for some of these nuclei which exhibit a more complex barrier structure, there is no unique way to extract a double-humped structure from the calculations. We give examples of such more complex structures, in particular the structure of the outer barrier region near ${}^{232}\mathrm{Th}$ and the occurrence of multiple fission modes. Because our complete results are too extensive to present in a paper of this type, our aim here is limited: (1) to fully present our model and the methods for determining the structure of the potential-energy surface, (2) to present fission thresholds for a large number of heavy elements, (3) to compare our results with the two-humped barrier structure deduced from experiment for actinide nuclei, and (4) to compare to additional fission-related data and other fission models.

We study first- and second-order theories of relativistic diffusion coupled to hydrodynamics under the approximation, valid at midrapidity in the BNL Relativistic Heavy Ion Collider (RHIC) and the CERN Large Hadron Collider (LHC), that conserved number densities are much smaller than the entropy density. We identify experimentally accessible quantities of interest and show that the first- and second-order theories may lead to radically different evolutions of these quantities. In the first-order theory the memory of the initial state is almost completely washed out, whereas in the second-order theory it is possible that freeze-out occurs at a time when transient dynamics is still on and the memory of the initial state remains. There are observational consequences that we touch upon. In the first-order theory, and for initial conditions when the second-order theory mimics the first-order theory, one may be able to put a bound on the diffusion constant.

We study the leading electroweak corrections in the precision measurement of the strange form factors. Specifically, we calculate the two-boson exchange (TBE), two-photon exchange (TPE) plus $\gamma Z$ exchange ($\gamma Z$E), and corrections with $\Delta (1232)$ excitation to the parity-violating asymmetry of the elastic electron-proton scattering. The interplay between nucleon and Δ contributions is found to depend strongly on the kinematics, as ${\delta }_{\Delta }$ begins as negligible at backward angles but becomes very large and negative and dominant at forward angles, while ${\delta }_N$ always stays positive and decreases monotonically with increasing $\epsilon$. The total TBE corrections to the extracted values of $G_E^s+\beta G_M^s$ in recent experiments of HAPPEX and G0 are, depending on kinematics, found to be large and range between $13\%$ and $-75\%$, but are found to be small in the case of A4 experiments.