Based on the isospin-dependent Boltzmann–Uehling–Uhlenbeck (IBUU04) transport model, we explored effects of in-medium $NN$ elastic scattering cross section and nuclear symmetry energy on the subthreshold pion production in the ${}^{132}\mathrm{Sn}+{}^{124}\mathrm{Sn}$ reaction. We find that, with the decrease of the incident beam energy, the effects of the in-medium $NN$ elastic scattering cross section on the ${\pi }^{-}/{\pi }^{+}$ ratio are larger than that of the symmetry energy, although the latter may be also larger. While keeping the effect of symmetry energy, the double ratio of ${\pi }^{-}/{\pi }^{+}$ from neutron-rich and neutron-poor reaction systems (with the same mass number of system) ${}^{132}\mathrm{Sn}+{}^{124}\mathrm{Sn}$ and ${}^{128}\mathrm{Pm}+{}^{128}\mathrm{Pm}$ almost fully cancels out the effects of the in-medium $NN$ elastic scattering cross section.

We compute the temporal evolution of the pressure anisotropy and bulk pressure of a massive gas using second-order viscous hydrodynamics and anisotropic hydrodynamics. We then compare our results with an exact solution of the Boltzmann equation for a massive gas in the relaxation time approximation. We demonstrate that, within second-order viscous hydrodynamics, the inclusion of the full set of kinetic coefficients, particularly the shear-bulk couplings, is necessary to properly describe the time evolution of the bulk pressure. We also compare the results of second-order hydrodynamics with those obtained using the anisotropic hydrodynamics approach. We find that anisotropic hydrodynamics and second-order viscous hydrodynamics including the shear-bulk couplings are both able to reproduce the exact evolution with comparable accuracy.

Measurements of two-particle correlation functions and the first five azimuthal harmonics, $v_1$ to $v_5$, are presented, using 28 ${\mathrm{nb}}^{-1}$ of $p+\text{Pb}$ collisions at a nucleon-nucleon center-of-mass energy of $\sqrt{s_{NN}}=5.02$ TeV measured with the ATLAS detector at the LHC. Significant long-range “ridgelike” correlations are observed for pairs with small relative azimuthal angle ($\left|\Delta \varphi \right|<\pi /3$) and back-to-back pairs ($\left|\Delta \varphi \right|>2\pi /3$) over the transverse momentum range $0.4<p_{\mathrm{T}}<12$ GeV and in different intervals of event activity. The event activity is defined by either the number of reconstructed tracks or the total transverse energy on the Pb-fragmentation side. The azimuthal structure of such long-range correlations is Fourier decomposed to obtain the harmonics $v_n$ as a function of $p_{\mathrm{T}}$ and event activity. The extracted $v_n$ values for $n=2$ to 5 decrease with $n$. The $v_2$ and $v_3$ values are found to be positive in the measured $p_{\mathrm{T}}$ range. The $v_1$ is also measured as a function of $p_{\mathrm{T}}$ and is observed to change sign around $p_{\mathrm{T}}\approx 1.5$–2.0 GeV and then increase to about 0.1 for $p_{\mathrm{T}}>4$ GeV. The $v_2\left(p_{\mathrm{T}}\right)$, $v_3\left(p_{\mathrm{T}}\right)$, and $v_4\left(p_{\mathrm{T}}\right)$ are compared to the $v_n$ coefficients in $\mathrm{Pb}+\mathrm{Pb}$ collisions at $\sqrt{s_{NN}}=2.76$ TeV with similar event multiplicities. Reasonable agreement is observed after accounting for the difference in the average $p_{\mathrm{T}}$ of particles produced in the two collision systems.

High spin states in neutron-rich ${}^{147}\mathrm{Ce}$ have been reinvestigated by measuring the triple- and fourfold $\gamma -\gamma$ coincidence data observed in the spontaneous fission of ${}^{252}\mathrm{Cf}$. The positive-parity band is expanded to spin (45/2) $\hslash$ and the negative-parity side band is expanded to spin (39/2) with a new third band connected to it. An octupole band structure with $s=+i$ was proposed. The systematic characteristics of the octupole correlations have been discussed. Reflection asymmetric shell model calculations for the octupole band structure of ${}^{147}\mathrm{Ce}$ are in good agreement with the experimental data.

The simple, longitudinal, and transverse wobblers are systematically studied within the framework of a collective Hamiltonian, where the collective potential and mass parameter included are obtained based on the tilted axis cranking approach. Solving the collective Hamiltonian by diagonalization, the energies and the wave functions of the wobbling states are obtained. The obtained results are compared with those by the harmonic approximation formula and particle rotor model. The wobbling energies calculated by the collective Hamiltonian are closer to the exact solutions by the particle rotor model than the harmonic approximation formula. It is confirmed that the wobbling frequency increases with the rotational frequency in simple and longitudinal wobbling motions while decreases in transverse wobbling motion. These variation trends are related to the stiffness of the collective potential in the collective Hamiltonian.

High-precision mass measurements of neutron-deficient Tl ($A=184$, 186, 190, 193–195, 198) isotopes as well as Pb ($A=202,208$), Fr ($A=207,208$), and Ra ($A=224$) are performed with the Penning-trap mass spectrometer ISOLTRAP at ISOLDE/CERN. The improved precision of the mass data now allows the study of subtle odd-even effects. The gradual development of collectivity with the removal of protons from the magic $Z=82$ core is analyzed by combining the new mass results with nuclear charge-radii data and mean-field model predictions.

Entrance channel effect is studied in the dynamics of ${}^{200}\mathrm{Pb}{}^{*}$ formed in ${}^{16}\mathrm{O}+{}^{184}\mathrm{W}$, ${}^{19}\mathrm{F}+{}^{181}\mathrm{Ta}$, and ${}^{30}\mathrm{Si}+{}^{170}\mathrm{Er}$ reactions over a wide range of excitation energies using the dynamical cluster-decay model (DCM) and Wong model. The effect of deformations up to ${\beta }_2$ along with optimum orientation is investigated in both formalisms. The fusion cross section is studied using the Wong model, which overestimates experimental data for ${}^{19}\mathrm{F}+{}^{181}\mathrm{Ta}$ and ${}^{30}\mathrm{Si}+{}^{170}\mathrm{Er}$ reactions and underestimates the data at few energies for ${}^{16}\mathrm{O}+{}^{184}\mathrm{W}$. However with the use of the extended $\ell$-summed Wong model, the overestimation is taken care and the cross sections are fitted nicely. The Wong-based calculations suggest that there might be some noncompound nucleus contribution at few energies for the ${}^{16}\mathrm{O}+{}^{184}\mathrm{W}$ channel, as the underestimation of the cross section persists even after the inclusion of deformation effects. This lead us to conclude that the formation of ${}^{200}\mathrm{Pb}{}^{*}$ compound nucleus depends on the choice of the incoming channel. In addition to this, the decay path of ${}^{200}\mathrm{Pb}{}^{*}$ is investigated using DCM. Although the overall decay pattern of compound nucleus ${}^{200}\mathrm{Pb}{}^{*}$ seems similar for all the chosen reactions, some signatures of variation are observed in fission and in the intermediate mass fragment region for the deformed fragmentation process. It is to be noted that with the inclusion of deformation, the decay pattern changes from symmetric to asymmetric, thereby suggesting that the deformation and orientation of decaying fragment are equally important in the formation as well as in the decay process of proton magic nuclear system ${}^{200}\mathrm{Pb}{}^{*}$. Prediction of the evaporation residue and fission cross sections at higher as well as at lower incident energies is also worked out. In addition to this, the dynamics of neighboring nuclei ${}^{192}{\mathrm{Pb}}^{*}$ and ${}^{202}{\mathrm{Pb}}^{*}$ is also analyzed.

We explore the influence of a temperature-dependent shear viscosity over entropy density ratio ${\eta }_s/s$ on the azimuthal anisotropies $v_2$ and $v_4$ of hadrons at various rapidities. We find that in $\mathrm{Au}+\mathrm{Au}$ collisions at full Relativistic Heavy Ion Collider energy, $\sqrt{s_{\mathrm{NN}}}=200\mathrm{GeV}$, the flow anisotropies are dominated by hadronic viscosity at all rapidities, whereas in $\mathrm{Pb}+\mathrm{Pb}$ collisions at the Large Hadron Collider energy, $\sqrt{s_{\mathrm{NN}}}=2760\mathrm{GeV}$, the flow coefficients are affected by the viscosity in both the plasma and hadronic phases at midrapidity, but the further away from midrapidity, the more dominant the hadronic viscosity becomes. We find that the centrality and rapidity dependence of the elliptic and quadrangular flows can help to distinguish different parametrizations of $({\eta }_s/s)\left(T\right)$. We also find that at midrapidity the flow harmonics are almost independent of the decoupling criterion, but they show some sensitivity to the criterion at backward and forward rapidities.

The lifetime of the $2_1^{+}$ state in ${}^{178}\mathrm{Pt}$ was measured by using fast-timing techniques with the high-purity Ge and ${\mathrm{LaBr}}_3:\mathrm{Ce}$ array using the ${}^{154}\mathrm{Gd}$(${}^{28}\mathrm{Si},4n$) reaction at a beam energy of 146 MeV. The deduced $B(E2,2_1^{+}\to 0_1^{+})$ strength is discussed in relation to the systematics of the previously reported $B(E2,2_1^{+}\to 0_1^{+})$ strengths in the light even-even ${}^{176–184}\mathrm{Pt}$ isotopes and compared with calculations of the generator coordinate method. The present results support a configuration-mixing interpretation for low-spin states in these light Pt isotopes.

We study antihalo effects on reaction cross sections ${\sigma }_{\mathrm{R}}$ for ${}^{14,15,16}\mathrm{C}$ scattering from a ${}^{12}\mathrm{C}$ target at 83 MeV/nucleon, using the $g$-matrix double-folding model. ${}^{15}\mathrm{C}$ is described by the ${}^{14}\mathrm{C}+n$ two-body model that reproduces the measured large $s$-wave spectroscopic factor, i.e., the shell inversion that the $1s_{1/2}$ orbital is lower than the $0d_{5/2}$ orbital in energy. ${}^{16}\mathrm{C}$ is described by the ${}^{14}\mathrm{C}+n+n$ three-body model with the phenomenological three-body force (3BF) that explains the measured small $s$-wave spectroscopic factor. The 3BF allows the single-particle energies of the ${}^{14}\mathrm{C}+n$ subsystem to depend on the position $r$ of the second neutron from the center of mass of the subsystem. The $1s_{1/2}$ orbital is lower than the $0d_{5/2}$ orbital for large $r$, but the shell inversion is restored for small $r$. Antihalo effects due to the “partial shell inversion” make ${\sigma }_{\mathrm{R}}$ for ${}^{16}\mathrm{C}$ smaller than that for ${}^{15}\mathrm{C}$. We also investigate projectile breakup effects on the mass-number dependence of ${\sigma }_{\mathrm{R}}$ with the continuum-discretized coupled-channel method.

We calculate the energy dependence of the asymmetry in the cross sections for circularly polarized photons on an unpolarized deuteron target in $d\vec{\gamma }\to np$ in pionless effective field theory. By matching the parity-violating low-energy constants to different sets of corresponding model parameters we obtain estimates for the asymmetry. In addition we calculate two possible figures of merit for the asymmetry in order to assess the preferred photon energy at which to perform a possible future experiment at a high-intensity photon source.

The structure of the Borromean nucleus ${}^9\mathrm{Be}$ ($\alpha +\alpha +n$) is addressed within a three-body approach using the analytical transformed harmonic oscillator method. The three-body formalism provides an accurate description of the radiative capture reaction rate for the entire temperature range relevant in astrophysics. At high temperatures, results match the calculations based on two-step sequential processes. At low temperatures, where the particles have no access to intermediate two-body resonances, the three-body direct capture leads to reaction rates larger than the sequential processes. These results support the reliability of the method for systems with several charged particles.

The characteristic properties of the hot nuclear matter existing at the time of fragment formation in multifragmentation events produced in the reaction ${}^{64}\mathrm{Zn}+{}^{112}\mathrm{Sn}$ at 40 MeV/nucleon are studied. A kinematical focusing method is employed to determine the multiplicities of evaporated light particles, associated with isotopically identified intermediate-mass fragments. From these data the primary isotopic yield distributions are reconstructed using a Monte Carlo method. The reconstructed yield distributions are in good agreement with the primary isotope distributions obtained from antisymmetrized molecular dynamics transport model simulations. Utilizing the reconstructed yields and power distribution, characteristic properties of the emitting source are examined. The primary mass distribution exhibits a power-law distribution with the critical exponent $A^{-2.3}$ for $A\ge 15$ isotopes but significantly deviate from that for lighter isotopes. Based on the modified Fisher model, the ratios of the Coulomb and symmetry energy coefficients relative to the temperature, $a_c/T$ and $a_{\mathrm{sym}}/T$, are extracted as a function of A. The extracted $a_{\mathrm{sym}}/T$ values are compared with results of the antisymmetrized molecular dynamics simulations using Gogny interactions with different density dependencies of the symmetry energy term. The calculated $a_{\mathrm{sym}}/T$ values show a close relation to the symmetry energy at the density at the time of fragment formation. From this relation the density of the fragmenting source is determined to be $\rho /{\rho }_0=0.63\pm 0.03$. Using this density, the symmetry energy coefficient and the temperature of fragmenting source are determined in a self-consistent manner as $a_{\mathrm{sym}}=24.7\pm 3.4$ MeV and $T=4.9\pm 0.2$ MeV.

We construct a model of baryon diffusion which has the desired properties of causality and analyticity. The model also has the desired property of colored noise, meaning that the noise correlation function is not a Dirac delta function in space and time; rather, it depends on multiple time and length constants. The model can readily be incorporated in 3+1-dimensional second-order viscous hydrodynamical models of heavy-ion collisions, which is particularly important at beam energies where the baryon density is large.

I extract the electrical conductivity ${\sigma }_0$ of the quark gluon plasma (QGP) and study the effects of magnetic field and chiral anomaly on soft photon azimuthal anisotropy, $v_2$, based on the thermal photon spectrum at $0.4\mathrm{GeV}<p_{\perp }<0.6\mathrm{GeV}$ at the Brookhaven Relativistic Heavy Ion Collider energy. As a basis for my analysis, I derive the behavior of retarded photon self-energy of a strongly interacting neutral plasma in hydrodynamic regime in the presence of magnetic field and chiral anomaly. By evolving the resulting soft thermal photon production rate over the realistic hydrodynamic background and comparing the results with the data from the PHENIX Collaboration, I found that the electrical conductivity at QGP temperature is in the range: $0.4<{\sigma }_0/\left(e^{2}T\right)<1.1$, which is comparable with recent studies on lattice. I also compare the contribution from the magnetic field and chiral anomaly to soft thermal photon $v_2$ with the data. I argue that at the CERN Large Hadron Collider, the chiral magnetic wave would give negative contribution to photon $v_2$.

Electromagnetic form factors of the nucleon in the spacelike region are investigated within the framework of a covariant and confining Nambu–Jona-Lasinio model. The bound-state amplitude of the nucleon is obtained as the solution of a relativistic Faddeev equation, where diquark correlations appear naturally as a consequence of the strong coupling in the color $\overline{3} qq$ channel. Pion degrees of freedom are included as a perturbation to the “quark-core” contribution obtained using the Poincaré covariant Faddeev amplitude. While no model parameters are fit to form-factor data, excellent agreement is obtained with the empirical nucleon form factors (including the magnetic moments and radii) where pion loop corrections play a critical role for $Q^2\lesssim 1{\mathrm{GeV}}^2$. Using charge symmetry, the nucleon form factors can be expressed as proton quark sector form factors. The latter are studied in detail, leading, for example, to the conclusion that the $d$-quark sector of the Dirac form factor is much softer than the $u$-quark sector, a consequence of the dominance of scalar diquark correlations in the proton wave function. On the other hand, for the proton quark sector Pauli form factors we find that the effect of the pion cloud and axial-vector diquark correlations overcomes the effect of scalar diquark dominance, leading to a larger $d$-quark anomalous magnetic moment and a form factor in the $u$-quark sector that is slightly softer than in the $d$-quark sector.

We compute the binding energy of triton with realistic statistical errors stemming from $NN$ scattering data uncertainties and the deuteron and obtain $E_t=-7.638\left(15\right)\mathrm{MeV}$. Setting the numerical precision as $\Delta E_t^{\mathrm{num}}\lesssim 1\mathrm{keV}$ we obtain the statistical error $\Delta E_t^{\mathrm{stat}}=15\left(1\right)\mathrm{keV}$ which is mainly determined by the channels involving relative $S$ waves. This figure reflects the uncertainty of the input $NN$ data, more than two orders of magnitude larger than the experimental precision $\Delta E_t^{\exp }=0.1\mathrm{keV}$, and sets a limit on the realistic precision that can be reached. This suggests an important reduction in the numerical precision and hence in the computational effort.

We present a lambda-nucleon Skyrme force suitable for reproducing the observed binding energies of the whole range of known light and heavy single-lambda hypernuclei with $A=5,...,208$. Notable exceptions such as ${}_{\Lambda }^9\mathrm{Be}$, featuring a well-developed cluster structure, are identified and examined in comparison with a cluster approach for the hypernuclear structure.