PaperPanorama

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
  4. 04

    From Non-interacting to Interacting Picture of Thermodynamics and Transport Coefficients for Quark Gluon Plasma

    Sarthak Satapathy🇮🇳 · Souvik Paul🇮🇳 · Ankit Anand🇮🇳 · Ranjesh Kumar🇮🇳 · Sabyasachi Ghosh🇮🇳

    We have attempted to build first some simplified model to map the interaction of quarks and gluons, which can be contained by their thermodynamical quantity like entropy density, obtained from calculation of lattice quantum chromo dynamics (LQCD). With respect to entropy density of the standard non-interacting massless quark gluon plasma (QGP), its interacting values from LQCD simulation are reduced as we go from higher to lower temperature through the cross-over of quark-hadron phase transition. By parameterizing increasing degeneracy factor or increasing interaction-fugacity or decreasing thermal width of quarks and gluons with temperature, we have matched LQCD data.Using that interaction picture, shear viscosity and electrical conductivity are calculated. For getting nearly perfect fluid nature of QGP, interaction might have some role when we consider temperature dependent thermal width.

    ↳ hep-phnucl-thJ.Phys.G(2020)·12 citations
  5. 05

    From Non-interacting to Interacting Picture of Quark Gluon Plasma in presence of magnetic field and its fluid property

    Jayanta Dey🇮🇳 · Sarthak Satapathy🇮🇳 · Ankita Mishra🇮🇳 · Souvik Paul🇮🇳 · Sabyasachi Ghosh🇮🇳

    We have attempted to build a parametric based simplified and analytical model to map the interaction of quarks and gluons in presence of magnetic field, which has been constrained by quark condensate and thermodynamical quantities like pressure, energy density etc., obtained from the calculation of lattice quantum chromodynamics. To fulfill that mapping, we have assumed a parametric temperature and magnetic field dependent degeneracy factor, average energy, momentum and velocity of quarks and gluons. Implementing this QCD interaction in calculation of transport coefficient at finite magnetic field, we have noticed that magnetic field and interaction both are two dominating sources, for which the values of transport coefficients can be reduced. Though the methodology is not so robust, but with the help of its simple parametric expressions, one can get a quick rough estimation of any phenomenological quantity, influenced by temperature and magnetic field dependent QCD interaction.

    ↳ hep-phnucl-thIJMPE(2021)·40 citations
  6. 06

    Light particle and quark chemical potentials from negatively to positively charged particle yield ratios corrected by removing strong and weak decays

    Hai-Ling Lao🇨🇳 · Ya-Qin Gao🇨🇳 · Fu-Hu Liu🇨🇳

    The yield ratios of negatively to positively charged pions (), negatively to positively charged kaons (), and anti-protons to protons () produced in mid-rapidity interval in central gold-gold (Au-Au) collisions, central lead-lead (Pb-Pb) collisions, and inelastic (INEL) or non-single-diffractive (NSD) proton-proton () collisions, as well as in forward rapidity region in INEL collisions are analyzed in the present work. Over an energy range from a few GeV to above 10 TeV, the chemical potentials of light flavor particles (pion, kaon, and proton) and quarks (up, down, and strange quarks) are extracted from the mentioned yield ratios in which the contributions of strong decay from high-mass resonance and weak decay from heavy flavor hadrons are removed. Most energy dependent chemical potentials show the maximum at about 4 GeV, while the energy dependent yield ratios do not show such an extremum.

    ↳ hep-phhep-exnucl-exnucl-thAdv.High Energy Phys.(2020)·4 citations
  7. 07

    Pairing in two-dimensional Fermi gases with a coordinate-space potential

    Tash Zielinski · Bernard Ross · Alexandros Gezerlis

    In this work we theoretically study pairing in two-dimensional Fermi gases, a system which is experimentally accessible using cold atoms. We start by deriving the mean-field pairing gap equation for a coordinate-space potential with a finite interaction range, and proceed to solve this numerically. We find that for sufficiently short effective ranges the answer is identical to the zero-range one. We then use Diffusion Monte Carlo to evaluate the total energy for many distinct particle numbers; we employ several variational parameters to produce a good ground-state energy and then use these results to extract the pairing gap across a number of interaction strengths in the strongly interacting two-dimensional crossover. Extracting the gap via the odd-even energy staggering, our microscopic results can be used as benchmarks for other theoretical approaches.

    ↳ cond-mat.quant-gasnucl-thPRA(2020)·4 citations

Affiliations

first authorsco-authorsvia INSPIRE