Nuclear matter

About: Nuclear matter is a research topic. Over the lifetime, 10180 publications have been published within this topic receiving 248261 citations.

Onset Transition to Cold Nuclear Matter from Lattice QCD with Heavy Quarks

Abstract: Lattice QCD at finite density suffers from a severe sign problem, which hasso far prohibited simulations of the cold and dense regime. Here we study theonset of nuclear matter employing a three-dimensional effective theory derivedby combined strong coupling and hopping expansions, which is valid for heavybut dynamical quarks and has a mild sign problem only. Its numericalevaluations agree between a standard Metropolis and complex Langevin algorithm,where the latter is free of the sign problem. Our continuum extrapolated dataclearly show a first order phase transition building up at $\mu_B \approx m_B$as the temperature approaches zero. An excellent description of the data isachieved by an analytic solution in the strong coupling limit.

Half-Skyrmions, Tensor Forces and Symmetry Energy in Cold Dense Matter

Abstract: In a previous article, the four-dimensional (4D) half-Skyrmion (or five-dimensional dyonic salt) structure of dense baryonic matter described in crystalline configuration in the large ${N}_{c}$ limit was shown to have nontrivial consequences on how antikaons behave in compressed nuclear matter with a possible implication for the ``ice-9'' phenomenon of deeply bound kaonic matter and condensed kaons in compact stars. We extend the analysis to make a further prediction on the scaling properties of hadrons that have a surprising effect on the nuclear tensor forces, the symmetry energy, and hence on the phase structure at high density. We treat this problem, relying on certain topological structures of chiral solitons. Combined with what can be deduced from hidden local symmetry for hadrons in a dense medium and the ``soft'' dilatonic degree of freedom associated with the trace anomaly of QCD, we uncover a novel structure of chiral symmetry in the ``supersoft'' symmetry energy that can influence the structure of neutron stars.

The quark-meson coupling model for Lambda, Sigma and Xi hypernuclei

Abstract: The quark-meson coupling (QMC) model, which has been successfully used to describe the properties of both infinite nuclear matter and finite nuclei, is applied to a systematic study of $\Lambda, \Sigma$ and $\Xi$ hypernuclei. Assumptions made in the present study are, (i) the (self-consistent) exchanged scalar, and vector, mesons couple only to the u and d quarks, and (ii) an SU(6) valence quark model for the bound nucleons and hyperon. The model automatically leads to a very weak spin-orbit interaction for the $\Lambda$ in a hypernucleus. Effects of the Pauli blocking at the quark level, particularly in the open, coupled, $\Sigma N - \Lambda N$ channel (strong conversion), is also taken into account in a phenomenological way.

Holographic Quark Matter and Neutron Stars.

Abstract: We use a top-down holographic model for strongly interacting quark matter to study the properties of neutron stars. When the corresponding equation of state (EOS) is matched with state-of-the-art results for dense nuclear matter, we consistently observe a first-order phase transition at densities between 2 and 7 times the nuclear saturation density. Solving the Tolman-Oppenheimer-Volkov equations with the resulting hybrid EOSs, we find maximal stellar masses in excess of two solar masses, albeit somewhat smaller than those obtained with simple extrapolations of the nuclear matter EOSs. Our calculation predicts that no quark matter exists inside neutron stars.