PaperPanorama
FAQ

Nuclear Theory·nucl-th

Wednesday·August 14, 2019

7 papers—3 primary·4 cross-listed

All7Primary3Cross-lists4
  1. 01

    Benchmark calculations of pure neutron matter with realistic nucleon-nucleon interactions

    M. Piarulli🇺🇸 · I. Bombaci🇮🇹 · D. Logoteta🇮🇹 · A. Lovato🇺🇸 · R. B. Wiringa🇺🇸

    We report benchmark calculations of the energy per particle of pure neutron matter as a function of the baryon density using three independent many-body methods: Brueckner-Bethe-Goldstone, Fermi hypernetted chain/single-operator chain, and auxiliary-field diffusion Monte Carlo. Significant technical improvements are implemented in the latter two methods. The calculations are made for two distinct families of realistic coordinate-space nucleon-nucleon potentials fit to scattering data, including the standard Argonne interaction and two of its simplified versions, and four of the new Norfolk -full chiral effective field theory potentials. The results up to twice nuclear matter saturation density show some divergence among the methods, but improved agreement compared to earlier work. We find that the potentials fit to higher-energy nucleon-nucleon scattering data exhibit a much smaller spread of energies.

    nucl-thastro-ph.HEastro-ph.SRPRC(2020)·76 citations
  2. 02

    Setting nonperturbative uncertainties on finite-temperature properties of neutron matter

    Arianna Carbone

    We present an error band on neutron matter properties at finite temperature (finite-T) which comprehends uncertainties on the nuclear interaction, the many-body method convergence, and the thermodynamical consistency of the approach. This study provides nonperturbative predictions for finite-T neutron matter employing chiral interactions which are selected on the basis of their performance in both finite nuclei and infinite matter at zero temperature. Since proper theoretical uncertainties at finite-T are still generally lacking, the band provided here represents a first step towards setting first-principles constraints on thermal aspects of the nuclear matter equation of state.

    nucl-thastro-ph.HEgr-qcnucl-exPRResearch(2020)·22 citations
  3. 03

    First-order phase transition from hypernuclear matter to deconfined quark matter obeying new constraints from compact star observations

    M. Shahrbaf🇮🇷 · D. Blaschke🇵🇱 · A. G. Grunfeld🇦🇷 · H. R. Moshfegh🇮🇷

    We reconsider the problem of the hyperon puzzle and its suggested solution by quark deconfinement within the two-phase approach to hybrid compact stars with recently obtained hadronic and quark matter equations of state. For the hadronic phase we employ the hypernuclear equation of state from the lowest order constrained variational method and the quark matter phase is described by a sufficiently stiff equation of state based on a color superconducting nonlocal Nambu-Jona-Lasinio model with constant (model nlNJLA) and with density-dependent (model nlNJLB) parameters. We study the model dependence of the phase transition obtained by a Maxwell construction. Our study confirms that also with the present set of equations of state quark deconfinement presents a viable solution of the hyperon puzzle even for the new constraint on the lower limit of the maximum mass from PSR J0740+6620. In this work we provide with model nlNJLB for the first time a hybrid star EoS with an intermediate hypernuclear matter phase between the nuclear and color superconducting quark matter phases, for which the maximum mass of the compact star reaches , in accordance with most recent constraints. In model nlNJLA such a phase cannot be realised because the phase transition onset is at low densities, before the hyperon threshold density is passed. We discuss possible consequences of the hybrid equation of state for the deconfinement phase transition in symmetric matter as it will be probed in future heavy-ion collisions at FAIR, NICA and corresponding energy scan programs at the CERN and RHIC facilities.

    nucl-thastro-ph.HEhep-phPRC(2020)·45 citations

Affiliations

first authorsco-authorsvia INSPIRE