We study charm production in ultrarelativistic heavy-ion collisions by using the parton-hadron-string dynamics (PHSD) transport approach. The initial charm quarks are produced by the pythia event generator tuned to fit the transverse-momentum spectrum and rapidity distribution of charm quarks from fixed-order next-to-leading logarithm calculations. The produced charm quarks scatter in the quark-gluon plasma (QGP) with the off-shell partons whose masses and widths are given by the dynamical quasiparticle model (DQPM), which reproduces the lattice QCD equation of state in thermal equilibrium. The relevant cross sections are calculated in a consistent way by employing the effective propagators and couplings from the DQPM. Close to the critical energy density of the phase transition, the charm quarks are hadronized into $D$ mesons through coalescence and fragmentation. The hadronized $D$ mesons then interact with the various hadrons in the hadronic phase with cross sections calculated in an effective Lagrangian approach with heavy-quark spin symmetry. Finally, the nuclear modification factor $R_{AA}$ and the elliptic flow $v_2$ of $D^0$ mesons from PHSD are compared with the experimental data from the STAR Collaboration for $\mathrm{Au}+\mathrm{Au}$ collisions at $\sqrt{s_{NN}}=200$ GeV. We find that in the PHSD the energy loss of $D$ mesons at high $p_T$ can be dominantly attributed to partonic scattering while the actual shape of $R_{AA}$ versus $p_T$ reflects the heavy-quark hadronization scenario, i.e., coalescence versus fragmentation. Also, the hadronic rescattering is important for the $R_{AA}$ at low $p_T$ and enhances the $D$-meson elliptic flow $v_2$.

We obtain a new equation of state for the nucleonic and hyperonic inner core of neutron stars that fulfils the 2 M _⊙ observations as well as the recent determinations of stellar radii below 13 km. The nucleonic equation of state is obtained from a new parameterization of the FSU2 relativistic mean-field functional that satisfies these latest astrophysical constraints and, at the same time, reproduces the properties of nuclear matter and finite nuclei while fulfilling the restrictions on high-density matter deduced from heavy-ion collisions. On the one hand, the equation of state of neutron star matter is softened around saturation density, which increases the compactness of canonical neutron stars leading to stellar radii below 13 km. On the other hand, the equation of state is stiff enough at higher densities to fulfil the 2 M _⊙ limit. By a slight modification of the parameterization, we also find that the constraints of 2 M _⊙ neutron stars with radii around 13 km are satisfied when hyperons are considered. The inclusion of the high magnetic fields present in magnetars further stiffens the equation of state. Hyperonic magnetars with magnetic fields in the surface of ∼10¹⁵ G and with values of ∼10¹⁸ G in the interior can reach maximum masses of 2 M _⊙ with radii in the 12–13 km range.

CompOSE (CompStar Online Supernovae Equations of State) is an online repository of equations of state (EoS) for use in nuclear physics and astrophysics, e.g., in the description of compact stars or the simulation of core-collapse supernovae and neutron-star mergers, see . The main services, offered via the website, are: a collection of data tables in a flexible and easily extendable data format for different EoS types and related physical quantities with extensive documentation and referencing; software for download to extract and to interpolate these data and to calculate additional quantities; webtools to generate EoS tables that are customized to the needs of the users and to illustrate dependencies of various EoS quantities in graphical form. This manual is an update of previous versions that are available on the CompOSE website, at , and that was originally published in the journal “Physics of Particles and Nuclei” with . It contains a detailed description of the service, containing a general introduction as well as instructions for potential contributors and for users. Short versions of the manual for EoS users and providers will also be available as separate publications. Graphical

We study dense nuclear matter and the chiral phase transition in a SU(2) parity doublet model at zero temperature. The model is defined by adding the chiral partner of the nucleon, the $N^{\prime }$, to the linear sigma model, treating the mass of the $N^{\prime }$ as an unknown free parameter. The parity doublet model gives a reasonable description of the properties of cold nuclear matter, and avoids unphysical behavior present in the standard SU(2) linear sigma model. If the $N^{\prime }$ is identified as the $N^{\prime }(1535)$, the parity doublet model shows a first order phase transition to a chirally restored phase at large densities, $\rho \approx 10{\rho }_0$, defining the transition by the degeneracy of the masses of the nucleon and the $N^{\prime }$. If the mass of the $N^{\prime }$ is chosen to be 1.2 GeV, then the critical density of the chiral phase transition is lowered to three times normal nuclear matter density, and for physical values of the pion mass, the first order transition turns into a smooth crossover.

We re-examine the equation of state for the nucleonic and hyperonic inner core of neutron stars that satisfies the 2M_⊙ observations as well as the recent determinations of stellar radii below 13 km, while fulfilling the saturation properties of nuclear matter and finite nuclei together with the constraints on the high-density nuclear pressure coming from heavy-ion collisions. The recent nucleonic FSU2R and hyperonic FSU2H models are updated in order to improve the behaviour of pure neutron matter at subsaturation densities. The corresponding nuclear matter properties at saturation, the symmetry energy, and its slope turn out to be compatible with recent experimental and theoretical determinations. We obtain the mass, radius, and composition of neutron stars for the two updated models and study the impact on these properties of the uncertainties in the hyperon–nucleon couplings estimated from hypernuclear data. We find that the onset of appearance of each hyperon strongly depends on the hyperon–nuclear uncertainties, whereas the maximum masses for neutron stars differ by at most 0.1M_⊙, although a larger deviation should be expected tied to the lack of knowledge of the hyperon potentials at the high densities present in the centre of 2M_⊙ stars. For easier use, we provide tables with the results from the FSU2R and FSU2H models for the equation of state and the neutron star mass–radius relation.

We study charmed baryon resonances that are generated dynamically within a unitary meson-baryon coupled-channel model that treats the heavy pseudoscalar and vector mesons on equal footing as required by heavy-quark symmetry. It is an extension of recent SU(4) models with $t$-channel vector-meson exchanges to an SU(8) spin-flavor scheme, but differs considerably from the SU(4) approach in how the strong breaking of the flavor symmetry is implemented. Some of our dynamically generated states can be readily assigned to recently observed baryon resonances, while others do not have a straightforward identification and require the compilation of more data as well as an extension of the model to $d$-wave meson-baryon interactions and $p$-wave coupling in the neglected $s$- and $u$-channel diagrams. Of several novelties, we find that the ${\Lambda }_c(2595)$, which emerged as a $ND$ quasibound state within the SU(4) approaches, becomes predominantly a $N{D}^{*}$ quasibound state in the present SU(8) scheme.