The proton elastic-scattering data on ${}^{4,6,8}$He and ${}^{6,7,9,11}$Li nuclei are analyzed over a wide range of incident energies below 160 MeV/nucleon using the single-folding optical model. The real part of the folding optical potential (OP) is calculated using the M3Y nucleon-nucleon interaction and microscopic densities. The Green's function Monte Carlo density is used for the stable nuclei, whereas the large-scale shell model density is used for the exotic nuclei. The high-energy approximation calculation is used for the volume imaginary OP. The spin-orbit and surface imaginary parts of the OP are constructed from the derivatives of the real and volume imaginary parts of the folded potentials, respectively. The volume integrals of the OPs are studied, and it is found that they show clear dependencies on energy and root-mean-square radii. Hence, it can be considered an important constraint for the choice of the optical potential. A new empirical formula is assumed and successfully applied for the real volume integrals. The obtained results of the differential and the reaction cross sections are in good agreement with the available experimental data. In general, this OP with few and limited fitting parameters, which have systematic behavior with incident energy, successfully describes the proton elastic-scattering data with stable and exotic light nuclei at energies below 160 MeV/nucleon.

Using a nonrelativistic potential model, we calculate the cross section for the leading-order gluon dissociation of $J/\psi$ by including the full gluon wave function. We find that the resulting cross section as a function of gluon energy is reduced by about a factor of three at its maximum value compared to that calculated in the dipole approximation that is usually adopted in theoretical studies. The effect of the reduced cross section on the $J/\psi$ dissociation width is, however, small at finite temperature.

The experimental rapidity distributions of negative pions were studied in minimum bias $d+{}^{12}$C, ${}^{12}$C + ${}^{12}$C, and ${}^{12}$C + ${}^{181}$Ta collisions at 4.2 GeV/$c$ per nucleon with 4π acceptance. The quantitative analysis of centrality dependence of the rapidity as well as transverse momentum versus rapidity spectra of the negative pions in the above collisions was performed by fitting the pion spectra with a Gaussian function. The widths of the rapidity spectra of ${\pi }^{-}$ mesons decreased in going from peripheral to central $d+{}^{12}$C, ${}^{12}$C + ${}^{12}$C, and ${}^{12}$C + ${}^{181}$Ta collisions. With an increase in collision centrality, the centers of the rapidity distributions of the negative pions shifted towards the target fragmentation region in the case of asymmetric $d+{}^{12}$C and ${}^{12}$C + ${}^{181}$Ta collisions and remained at the midrapidity position for symmetric ${}^{12}$C + ${}^{12}$C collisions. The extracted widths and locations of the centers of transverse momentum versus rapidity spectra of the negative pions did not depend within uncertainties on the masses of the projectile and target nuclei as well as the collision centrality. The experimental results were compared systematically with the corresponding results extracted by using a version of the quark-gluon-string model adapted to intermediate energies.

Short-lived radionuclides (SLRs) with lifetimes $\tau$ $<$ 100 Myr are known to have been extant when the Solar System formed over 4.5 billion years ago. Identifying the sources of SLRs is important for understanding the time scales of Solar System formation and processes that occurred early in its history. Extinct ${}^{36}$Cl ($t$${}_{1/2}=$ 0.301 Myr) is thought to have been produced by interaction of solar energetic particles, emitted by the young Sun, with gas and dust in the nascent Solar System. However, models that calculate SLR production in the early Solar System lack experimental data for the ${}^{36}$Cl production reactions. We present here the first measurement of the cross section of one of the main ${}^{36}$Cl production reactions, ${}^{33}$S($\alpha$,$p$)${}^{36}$Cl, in the energy range 0.70–2.42 MeV/nucleon. The cross-section measurement was performed by bombarding a target and collecting the recoiled ${}^{36}$Cl atoms produced in the reaction, chemically processing the samples, and measuring the ${}^{36}$Cl/Cl ratio of the activated samples with accelerator mass spectrometry. The experimental results were found to be systematically higher than the cross sections used in previous local irradiation models and other Hauser-Feshbach calculated predictions. However, the effects of the experimentally measured cross sections on the modeled production of ${}^{36}$Cl in the early Solar System were found to be minimal. Reaction channels involving S targets dominate ${}^{36}$Cl production, but the astrophysical event parameters can dramatically change each reaction's relative contribution.

$\Lambda$-hypernuclear magnetic moments have been studied self-consistently in time-odd triaxial relativistic mean-field approach with newly proposed $\Lambda$-meson interactions. The $\omega \Lambda \Lambda$ tensor coupling highly reduces the polarized Dirac magnetic moment. The deviation of the magnetic moment from the Schmidt value $\Delta \mu$ is related to effective nucleon-meson interaction. A large deviation $\Delta \mu$ with $l_{\Lambda }\ne 0$ is found to exist only in medium-mass hypernuclei.

Ground-state phase transitions in odd nuclei are examined. Especially, the phase transitions in odd-odd nuclei are revealed. It is found that odd-even effects may reach their maximal or minimal values around the critical point at $N=90$; the signals of phase transition in odd nuclei are greatly enhanced relative to those in the adjacent even-even species. Moreover, a pairing model analysis of the phase transition in Sm isotopes indicates that the critical behaviors related to pairing may be driven by the decrease in the pair strength $G$ with a sudden flattening in $\Delta G$ around the critical point.

We investigate the effects of finite baryon chemical potential on the transport properties of a hadron resonance gas. We find that a hadron resonance gas with large baryon number density is closer to the ideal fluid limit than the corresponding gas with zero baryon number. This suggests that the system created at the Relativistic Heavy Ion Collider (RHIC) at lower collision energies may behave as a fluid, with an effective fluidity close to the one found at RHIC's highest energy near phase transition. This might explain why the differential elliptic flow coefficient measured at lower collisional energies at RHIC is similar to the one observed at high energies.

We have calculated the shear viscosity coefficient $\eta$ of the strongly interacting matter in the relaxation time approximation, where a quasiparticle description of quarks with their dynamical masses is considered from the Nambu-Jona-Lasinio model. Due to the thermodynamic scattering of quarks with pseudoscalar-type condensate (i.e., pion), a nonzero Landau damping will be acquired by the propagating quarks. This Landau damping may be obtained from the Landau cut contribution of the in-medium self-energy of a quark-pion loop, which is evaluated in the framework of real-time thermal field theory.

We present results of calculations based on the Skyrme energy density functional that include arbitrary mixing between protons and neutrons. In this framework, single-particle states are superpositions of proton and neutron components and the energy density functional is fully invariant with respect to three-dimensional rotations in the isospin space. The isospin of the system is controlled by means of the isocranking method, which carries the standard cranking approach over to isospin space. We show numerical results of the isocranking calculations performed for isobaric analog states in the $A=14$ and $A=40–56$ nuclei. We also present results obtained for high-isospin states in ${}^{48}$Cr, with constraints on the isospin implemented using the augmented Lagrange method.

The band-head systematic ground-state spins and parities of one-quasineutron states along an odd-$A$ Mo isotopic chain are studied by using the quasiparticle-phonon coupling plus rotor model. Within this model, the individual excitation is retained in a deformed Nilsson average field and a monopole pairing interaction from BCS. The vibrational collective motion is derived from the quadrupole phonon term of the Tamm-Dancoff approximation. The two effects of recoil and Coriolis forces are included with the assumption of a symmetric rotational motion. To determine the intrinsic states of an odd nucleus, we have adopted an exact diagonalization in the basis of one-quasiparticle and quasiparticle-phonon states. The structural evolution via the ground and low-lying one-quasineutron states is systematically studied for ${}^{103,105,107}$Mo with comparison to the available experimental data.

The excited states in the odd-$A$ ${}^{197}$Tl nucleus have been studied by populating them using the ${}^{197}$Au($\alpha$, 4$n$)${}^{197}$Tl reaction at a beam energy of 48 MeV. The $\gamma -\gamma$ coincidence data were taken using a combination of clover, low-energy photon spectrometer (LEPS), and single-crystal high-purity germanium (HPGe) detectors. Precise spin and parity assignments of the excited states have been done through polarization and directional correlation from oriented states (DCO) measurements. A new band structure has been identified and evidence for a possible intruder $\pi i_{13/2}$ state has been found for the first time. Possible configurations of the observed bands have been discussed. The total Routhian surface calculations have been performed to study the shape of ${}^{197}$Tl for different configurations.

Applying the sum rule approach, we investigate the energy of a soft dipole motion in $\Lambda$ hypernuclei, which results from a dipole oscillation of a $\Lambda$ hyperon against the core nucleus. To this end, we systematically study single-$\Lambda$ hypernuclei, from ${}_{\Lambda }^{16}$O to ${}_{\Lambda }^{208}$Pb, for which the ground-state wave function is obtained in the frame-work of Hartree-Fock method with several Skyrme-type $\Lambda N$ interactions. Our results indicate that the excitation energy of the soft dipole $\Lambda$ mode, $E_{sd\Lambda }$, decreases as the mass number increases. We find that the excitation energy is well parametrized as $E_{sd\Lambda }=26.6A^{-1/3}+11.2A^{-2/3}$ MeV for the SkM* $NN$ interaction and $E_{sd\Lambda }=21.3A^{-1/3}+22.6A^{-2/3}$ MeV for the SIII $NN$ interaction as a function of mass number $A$.

Sub-barrier capture reactions following neutron-pair transfer are proposed to be used for the indirect study of the neutron-neutron correlation in the surface region of a nucleus. The strong effect of dineutron-like cluster transfer stemming from the surface of magic and nonmagic nuclei ${}^{18}$O, ${}^{48}$Ca, ${}^{64}$Ni, ${}^{94,96}$Mo, ${}^{100,102,104}$Ru, ${}^{104,106,108}$Pd, and ${}^{112,114,116,118,120,124,132}$Sn is demonstrated. The dominance of the two-neutron transfer channel in the vicinity of the Coulomb barrier is further supported by time-dependent mean-field approaches.

Among the oscillatory modes of neutron stars or quark stars, the $r$-mode is particularly interesting since it couples strongly to gravitational waves, which rapidly remove angular momentum from the star and spin it down. The $r$-mode can also provide a penetrating probe into the composition of such objects, where matter is compressed to the most extreme densities possible in nature. At these densities, exotic matter composed of subatomic particles—quarks—can manifest many interesting phases. We construct a model for quark stars that is a step towards resolving the puzzle of rapidly spinning pulsars in low mass X-ray binaries. The explanation makes use of a crystalline superconducting quark crust that is sufficiently robust to damp the $r$-mode, keeping the star spinning quickly. A crust made of neutrons or non-superconducting quark matter cannot damp the $r$-mode as effectively, thus, the fast spin rates observed in some LMXB pulsars may be an astrophysical signature of superconducting quark matter.

Fission dynamics properties of the Barcelona-Catania-Paris-Madrid energy density functional are explored with mean-field techniques. Potential energy surfaces as well as collective inertias relevant in the fission process are computed for several nuclei where experimental data exist. Inner and outer barrier heights as well as fission isomer excitation energies are reproduced quite well in all the cases. The spontaneous fission half-lives $t_{\mathrm{sf}}$ are also computed using the standard semiclassical approach and the results are compared with the experimental data. The experimental trend with mass number is reasonably well reproduced over a range of 27 orders of magnitude. However, the theoretical predictions suffer from large uncertainties when the quantities that enter the spontaneous fission half-life formula are varied. Modifications of only a few per cent in the pairing correlation strengths strongly modify the collective inertias with a large impact on the spontaneous fission lifetimes in all the nuclei considered. Encouraged by the quite satisfactory description of the trend of fission properties with mass number, we explore the fission properties of the even-even uranium isotope chain from ${}^{226}$U to ${}^{282}$U. Very large lifetimes are found beyond $A=256$ with a peak at neutron number $N=184$.

We extend the self-consistent Green's functions formalism to take into account three-body interactions. We analyze the perturbative expansion in terms of Feynman diagrams and define effective one- and two-body interactions, which allows for a substantial reduction of the number of diagrams. The procedure can be taken as a generalization of the normal ordering of the Hamiltonian to fully correlated density matrices. We give examples up to third order in perturbation theory. To define nonperturbative approximations, we extend the equation-of-motion method in the presence of three-body interactions. We propose schemes that can provide nonperturbative resummation of three-body interactions. We also discuss two different extensions of the Koltun sum rule to compute the ground state of a many-body system.

The universality of the critical-temperature-included fluctuation model (CTFM) in explaining the evolution of the giant dipole resonance (GDR) width as a function of angular momentum is examined in light of recent experimental data on ${}^{144}$Sm and ${}^{152}$Gd. We compare both data sets with the phenomenological formula based on the CTFM and the thermal shape fluctuation model (pTSFM). The CTFM describes both data sets reasonably well using the actual ground state GDR width (${\Gamma }_0$), whereas the pTSFM describes the ${}^{144}$Sm data well but is unable to explain the ${}^{152}$Gd data using a single value of ${\Gamma }_0$ for the two excitation energies. These interesting results clearly indicate that the phenomenological CTFM can be used universally to describe the evolution of the GDR width with both angular momentum and temperature in the entire mass region. Moreover, it should provide insights into the modification of the TSFM.

Recent ground-state-focused studies of the tensor effects in the mean-field framework are our starting point. On the basis of phenomenological arguments, we indicate regions for acceptable values of the parameters that are associated with the tensor effective forces within both the Skyrme and the Gogny models. We identify acceptable signs and values of the parameters by making an adjustment on the neutron $1f$ spin-orbit splitting for the nuclei ${}^{40}$Ca, ${}^{48}$Ca, and ${}^{56}$Ni. The first nucleus is not used to adjust the tensor parameters because it is spin-saturated, but is employed to tune the spin-orbit strength. One of the main conclusions of this work is that some existing Skyrme parametrizations containing the tensor force should not be employed because the wrong sign of the tensor parameters does not lead to the correct behavior (by comparing with the experimental results). This study also allows us to better constrain the tensor parameters in the Gogny case, where much less work is published and boundaries and signs for the parameters have not been analyzed so far.