PaperPanorama

Nuclear Theory·nucl-th

Monday·November 19, 2018

3 papers3 primary·0 cross-listed

  1. 01

    Parameter Optimisation for the Latest Quark-Meson Coupling Energy Density Functional

    Kay Marie L. Martinez🇦🇺 · Anthony William Thomas🇦🇺 · Jirina R. Stone🇬🇧 · Pierre A. M. Guichon🇫🇷

    The Quark--Meson--Coupling (QMC) model self-consistently relates the dynamics of the internal quark structure of a hadron to the relativistic mean fields arising in nuclear matter. It offers a natural explanation to some open questions in nuclear theory, including the origin of many-body nuclear forces and their saturation, the spin-orbit interaction and properties of hadronic matter at a wide range of densities. The QMC energy density functionals QMC-I and QMC-I have been successfully applied to calculate ground state observables of finite nuclei in the Hartree-Fock + BCS approximation, as well as to predict properties of dense nuclear matter and cold non-rotating neutron stars. Here we report the latest development of the model, QMC-II, extended to include higher order self-interaction of the meson. A derivative-free optimization algorithm has been employed to determine a new set of the model parameters and their statistics, including errors and correlations. QMC-II predictions for a wide range of properties of even-even nuclei across the nuclear chart, with fewer adjustable parameters, are comparable with other models. Predictions of ground state binding energies of even-even isotopes of superheavy elements with Z96 are particularly encouraging.

    nucl-thPRC(2019)·24 citations
  2. 02

    Nuclear symmetry energy and hadron-quark mixed phase in neutron stars

    X. H. Wu🇨🇳 · H. Shen🇨🇳

    We study the hadron-quark mixed phase, which may occur in the interior of neutron stars. The relativistic mean-field model is employed to describe the hadronic phase, while the Nambu--Jona-Lasinio model is used for the quark phase. We examine the effects of nuclear symmetry energy in the hadronic phase and repulsive vector interaction in the quark phase. For the treatment of hadron-quark mixed phase, we describe and compare four methods: (1) energy minimization method; (2) coexisting phases method; (3) Gibbs construction; and (4) Maxwell construction. The finite-size effects like surface and Coulomb energies are taken into account in the energy minimization and coexisting phases methods, which play a key role in determining the pasta configuration during the hadron-quark phase transition. It is found that massive neutron stars may contain hadron-quark pasta phases, but pure quark matter is unlikely to occur in the interior of neutron stars.

    nucl-thPRC(2019)·44 citations
  3. 03

    Relaxation of baryon diffusion flow in QGP medium and its impact on thermal photon spectra

    Sukanya Mitra🇺🇸

    In the current work the time evolution of baryon diffusion flow within the scope of second order relativistic hydrodynamic theory has been studied for a 2-component quark-gluon system. The relaxation time for diffusion flow is estimated using the Grad's moment method of many particle kinetic theory. The temperature dependence of relaxation time for diffusion flow has been obtained for different quark chemical potentials. Finally, the diffusion equation has been solved for a dimensional boost invariant system and the effect of diffusion flow has been studied on the thermal photon spectra in a baryon rich environment. The present analysis on the role of baryon number diffusion in influencing the properties of hot QCD medium could be relevant for the baryon rich matter explorations in upcoming experimental facilities.

    nucl-th0 citations

Affiliations

first authorsco-authorsvia INSPIRE