The martini numerical simulation allows for direct comparison of theoretical model calculations and the latest results for dijet asymmetry from the ATLAS and CMS collaborations. In this paper, partons are simulated as undergoing radiative and collisional processes throughout the evolution of central lead-lead collisions at the Large Hadron Collider. Using hydrodynamical background evolution determined by a simulation which fits well with the data on charged particle multiplicities from ALICE and a value of ${\alpha }_s\approx 0.25$–0.3, the dijet asymmetry is found to be consistent with partonic energy loss in a hot, strongly interacting medium.

The space-time propagation of heavy quarks in ultrarelativistic heavy ion collisions is studied within the partonic transport model Boltzmann approach of multiparton scatterings (BAMPS). In this model heavy quarks interact with the partonic medium via binary scatterings. The cross sections for these interactions are calculated with leading-order perturbative QCD, but feature a more precise Debye screening derived within the hard thermal loop approximation and obey the running of the coupling. Within this framework the elliptic flow and the nuclear modification factor of heavy quarks are computed for the BNL Relativistic Heavy Ion Collider (RHIC) and the CERN Large Hadron Collider (LHC) energies and compared to available experimental data. It is found that binary scatterings alone cannot reproduce the data and therefore radiative corrections have to be taken into account.

Monte Carlo simulations are used to compute the centrality dependence of the odd moments of the initial eccentricity ${\varepsilon }_{n+1}$, relative to the even-order ($n$) participant planes ${\Psi }_n$ in Au + Au collisions. The results obtained for two models of the eccentricity—the Glauber and the factorized Kharzeev-Levin-Nardi (fKLN) models—indicate magnitudes which are essentially zero. They suggest that a possible correlation between the orientations of the the odd and even participant planes (${\Psi }_{n+1}$ and ${\Psi }_n$, respectively) does not have a significant influence on the calculated eccentricities. An experimental verification test for correlations between the orientations of the the odd and even participant planes is also proposed.

Jet production in PbPb collisions at a nucleon-nucleon center-of-mass energy of 2.76 TeV was studied with the Compact Muon Solenoid (CMS) detector at the LHC, using a data sample corresponding to an integrated luminosity of $6.7\mu$b${}^{-1}$. Jets are reconstructed using the energy deposited in the CMS calorimeters and studied as a function of collision centrality. With increasing collision centrality, a striking imbalance in dijet transverse momentum is observed, consistent with jet quenching. The observed effect extends from the lower cutoff used in this study (jet $p_{\mathrm{T}}=120$ GeV/c) up to the statistical limit of the available data sample (jet $p_{\mathrm{T}}\approx 210$ GeV/c). Correlations of charged particle tracks with jets indicate that the momentum imbalance is accompanied by a softening of the fragmentation pattern of the second most energetic, away-side jet. The dijet momentum balance is recovered when integrating low transverse momentum particles distributed over a wide angular range relative to the direction of the away-side jet.

Shell-model calculations using realistic interactions reveal that the ground and low-lying yrast states of the $N=Z$ nucleus ${}_{46}^{92}$Pd are mainly built upon isoscalar neutron-proton pairs, each carrying the maximum angular momentum $J=9$ allowed by the shell $0g_{9/2}$, which is dominant in this nuclear region. This structure is different from that found in the ground and low-lying yrast states of all other even-even nuclei studied so far. The low-lying spectrum of excited states generated by such correlated neutron-proton pairs has two distinctive features: (i) the levels are almost equidistant at low energies and (ii) the transition probability $I\to I-2$ is approximately constant and strongly selective. This unique mode is shown to replace normal isovector pairing as the dominant coupling scheme in $N=Z$ nuclei approaching the doubly magic nucleus ${}^{100}$Sn.

Covariant density functional theory is used to investigate quantum shape fluctuation in ${}^{16}$C and other even-even carbon isotopes. Long-range correlations beyond the mean-field approximation are taken into account by configuration mixing of wave functions with triaxial shapes and by restoring the spontaneously broken rotational symmetry through a three-dimensional angular-momentum projection. The systematics of the excitation energy of the $2_1^{+}$ state and the $B(E2:2_1^{+}\to 0_1^{+})$ values in carbon isotopes are reproduced rather well. Decoupled structures with rather different deformations for neutrons and protons have been found in ${}^{16,18,20}$C. In addition, the effects of shape fluctuations in $\beta$ and $\gamma$ deformations on the low-lying excited states of these nuclei are examined.

Changes in the nuclear charge radii of lithium isotopes were determined using a combination of precise isotope shift measurements and theoretical atomic structure calculations. We discuss the choice of the reference isotope for absolute charge radii determinations in the lithium isotopic chain and report a new value for the charge radius of ${}^6$Li, based on the analysis of the world scattering data. A summary of the lithium nuclear charge radii obtained in this way is presented. Additionally, new calculations in fermionic molecular dynamics for the lithium isotopes were performed. We summarize the status of the lithium nuclear charge radii, magnetic dipole and electric quadrupole moments from experimental investigations and compare them to the results of various microscopic and three-body nuclear models.

A set of states in ${}^{10}$Be have very large α widths and very small neutron strengths. We review the data and investigate whether they are ($sd$)${}^2$ states and/or α clusters.

Excited states of neutron-rich nucleus ${}^{82}$Ge were studied from the spontaneous fission of ${}^{252}$Cf. Eleven new transitions and seven new levels in ${}^{82}$Ge were identified by using $X$(Dy)-$\gamma$-$\gamma$ and $\gamma$-$\gamma$-$\gamma$ triple coincidences. Possible excited deformed rotational bands are observed, for the first time, in this nuclear region. Coexistence of the spherical ground and deformed excited shapes is proposed in ${}^{82}$Ge. These deformed rotational bands can be formed by two-particle, two-hole excitations with the 0${}^{+}$ pairing energy states of the $\nu 9/2{\left[404\right]}^{-2}\otimes 1/2{\left[431\right]}^2$ configuration across the $N=50$ closed shell.

The ratio of shear viscosity ($\eta$) to entropy density ($s$) for an equilibrated system is investigated in intermediate-energy heavy-ion collisions below 100$A$ MeV within the framework of the Boltzmann-Uehling-Uhlenbeck model. After the collision system almost reaches a local equilibration, the temperature, pressure and energy density are obtained from the phase-space information and $\eta /s$ is calculated using the Green-Kubo formulas. The results show that $\eta$/$s$ decreases with incident energy and tends toward a smaller value around 0.5, which is not so drastically different from the BNL Relativistic Heavy Ion Collider results in the present model.

A measurement for studying the mass dependence of dilepton interferometry in relativistic heavy-ion collision experiments as a tool to characterize the quark gluon phase is proposed. In calculations involving dileptons, we show that the mass dependence of radii extracted from the virtual photon (dilepton) interferometry provide access to the development of collective flow with time. It is argued that the nonmonotonic variation of Hanbury Brown-Twiss radii with invariant mass of the lepton pairs signals the formation of quark gluon plasma in heavy ion collisions. Our proposal of experimentally measuring the ratio, $R_{\mathrm{out}}/R_{\mathrm{side}}$ for dileptons can be used to estimate the average lifetimes of the partonic as well as the hadronic phases.

Pair correlations between large transverse momentum neutral pion triggers ($p_T=4\text{--}7$ GeV/$c$) and charged hadron partners ($p_T=3\text{--}7$ GeV/$c$) in central (0%–20%) and midcentral (20%–60%) $\text{Au}+\text{Au}$ collisions at $\sqrt{s_{{}_{NN}}}=200$ GeV are presented as a function of trigger orientation with respect to the reaction plane. The particles are at larger momentum than where jet shape modifications have been observed, and the correlations are sensitive to the energy loss of partons traveling through hot dense matter. An out-of-plane trigger particle produces only $26\pm 20\%$ of the away-side pairs that are observed opposite of an in-plane trigger particle for midcentral (20%–60%) collisions. In contrast, near-side jet fragments are consistent with no suppression or dependence on trigger orientation with respect to the reaction plane. These observations are qualitatively consistent with a picture of little near-side parton energy loss either due to surface bias or fluctuations and increased away-side parton energy loss due to a long path through the medium. The away-side suppression as a function of reaction-plane angle is shown to be sensitive to both the energy loss mechanism and the space-time evolution of heavy-ion collisions.

We employ the UrQMD transport + hydrodynamics hybrid model to estimate the effects of a separation of the hot equilibrated core and the dilute corona created in high-energy heavy-ion collisions. It is shown that the fraction of the system that can be regarded as an equilibrated fireball changes over a wide range of energies. This has an impact, especially on strange particle abundances. We show that such a core corona separation allows for an improvement in the description of strange particle ratios and flow as a function of beam energy as well as strange particle yields as a function of centrality.

Skyrme-like energy density functionals are built upon new ab initio calculations of nuclear matter which reproduce the empirical saturation properties. These calculations are performed in the framework of the Brueckner-Hartree-Fock approximation with consistent two- and three-body forces. The Skyrme parametrizations are obtained from a simultaneous fit of the spin-isospin components of the potential energy of symmetric nuclear matter and of the experimental energies and charge radii of a number of closed-shell and closed-subshell nuclei. These parametrizations are tested on the energies and charge radii of the Sn isotopic chain and on the ${}^{208}$Pb giant resonances, showing a substantial improvement of the LNS functional obtained in a previous fit. The comparison with standard Skyrme forces can give some hints on how to reconcile nuclear matter and finite nuclei.

The interrelation of the quadrupole deformation and clusterization is investigated in the example of the ${}^{56}$Ni nucleus. The shape isomers, including superdeformed and hyperdeformed states, are obtained as stability regions of the quasidynamical U(3) symmetry based on a Nilsson calculation. Their possible binary clusterizations are investigated by considering both the consequences of the Pauli exclusion principle and the energetic preference.

Laser spectroscopy was performed on the ${}^{72,74,76,78}$Ga isotopes at On-Line Isotope Mass Separator (ISOLDE) facility, CERN. Ground-state nuclear spins and moments were extracted from the measured hyperfine spectra. The results are compared to shell-model calculations, which provide a detailed probe of the nuclear wave function. The spin is established from the shape of the hyperfine structure and the parity inferred from a comparison of shell-model calculations with the measured nuclear moments. The ground states of ${}^{76,78}$Ga are both assigned a spin and parity of $I^{\pi }=2^{-}$, while ${}^{74}$Ga is tentatively assigned as $I^{\pi }=3^{-}$. For ${}^{72}$Ga, the results are consistent with the previous $I=3$ assignment.

Cross sections were measured by the activation technique for the nuclear processes ${}^{192}$Os(α,$d$+$\mathit{pn}$+$\mathit{np}$)${}^{194}$Ir${}^m$${}^{,\mathrm{g}}$ up to α-particle energies of 39 MeV. From the measured data the isomeric cross-section ratio was deduced as a function of projectile energy. The present experimental data as well as those for the ${}^{194}$Pt($n$,$p$)${}^{194}$Ir${}^m$${}^{,\mathrm{g}}$ reaction, given in the literature, were compared with the results of nuclear model calculations using the code talys, which combines the statistical, precompound, and direct interactions. In general, the experimental data were reproduced well by the model calculations, which were done using relatively low values of η (i.e., ${\Theta }_{\mathrm{eff}}/{\Theta }_{\mathrm{rigid}}$). The results provide more evidence for the mass dependence of η. The level density parameter for ${}^{194}$Ir was determined unambiguously.

The relation between the low-energy constants appearing in the effective field theory description of the $\Lambda N\to NN$ transition potential and the parameters of the one-meson-exchange model previously developed is obtained. We extract the relative importance of the different exchange mechanisms included in the meson picture by means of a comparison to the corresponding operational structures appearing in the effective approach. The ability of this procedure to obtain the weak baryon-baryon-meson couplings for a possible scalar exchange is also discussed.

An incomplete particle identification distorts the observed event-by-event fluctuations of the hadron chemical composition in nucleus-nucleus collisions. A new experimental technique called the identity method was recently proposed. It eliminated the misidentification problem for one specific combination of the second moments in a system of two hadron species. In the present paper, this method is extended to calculate all the second moments in a system with an arbitrary number of hadron species. Special linear combinations of the second moments are introduced. These combinations are presented in terms of single-particle variables and can be found experimentally from the event-by-event averaging. The mathematical problem is then reduced to solving a system of linear equations. The effect of incomplete particle identification is fully eliminated from the final results.

Shear and bulk viscosities of deconfined gluonic matter are investigated within an effective kinetic theory by describing the strongly interacting medium phenomenologically in terms of quasiparticle excitations with medium-dependent self-energies. We show that the resulting transport coefficients reproduce the parametric dependencies on temperature and coupling obtained in perturbative QCD at large temperatures and small running coupling. The extrapolation into the nonperturbative regime results in a decreasing specific shear viscosity with decreasing temperature, exhibiting a minimum in the vicinity of the deconfinement transition, while the specific bulk viscosity is sizable in this region, falling off rapidly with increasing temperature. The temperature dependence of specific shear and bulk viscosities found within this quasiparticle description of the pure gluon plasma is in agreement with available lattice QCD results.