scholarly journals Toward a unified equation of state for multi-messenger astronomy

2020 ◽  
Vol 643 ◽  
pp. A82 ◽  
Author(s):  
M. Marczenko ◽  
D. Blaschke ◽  
K. Redlich ◽  
C. Sasaki
Keyword(s):  
Equation Of State ◽  
Degrees Of Freedom ◽  
Chiral Symmetry Breaking ◽  
Light Quark ◽  
Mean Field ◽  
Heavy Ion ◽  
Compact Stars ◽  
Model Parameters ◽  
Nucleon Matter ◽  
Ion Collision

Aims. We aim to present a first step in developing a benchmark equation-of-state (EoS) model for multi-messenger astronomy that unifies the thermodynamics of quark and hadronic degrees of freedom. Methods. A Lagrangian approach to the thermodynamic potential of quark-meson-nucleon matter was used. In this approach, dynamical chiral-symmetry breaking is described by the scalar mean-field dynamics coupled to quarks and nucleons and their chiral partners, whereby its restoration occurs in the hadronic phase by parity doubling, as well as in the quark phase. Quark confinement was achieved by an auxiliary scalar field that parametrizes a dynamical infrared cut-off in the quark sector, serving as an ultraviolet cut-off for the nucleonic phase space. The gap equations were solved for the isospin-symmetric case, as well as for neutron star (NS) conditions. We also calculated the mass-radius (MR) relation of NSs and their tidal deformability (TD) parameter. Results. The obtained EoS is in accordance with nuclear matter properties at saturation density and with the flow constraint from heavy ion collision experiments. For isospin-asymmetric matter, a sequential occurrence of light quark flavors is obtained, allowing for a mixed phase of chirally-symmetric nucleonic matter with deconfined down quarks. The MR relations and TDs for compact stars fulfill the constraints from the latest astrophysical observations for PSR J0740+6620, PSR J0030+0451, and the NS merger GW170817, whereby the tension between the maximum mass and compactness constraints rather uniquely fixes the model parameters. The model predicts the existence of stars with a core of chirally restored but purely hadronic (confined) matter for masses beyond 1.8 M⊙. Stars with pure-quark matter cores are found to be unstable against the gravitational collapse. This instability is shifted to even higher densities if repulsive interactions between quarks are included.

scholarly journals From Heavy-Ion Collisions to Compact Stars: Equation of State and Relevance of the System Size

Universe ◽  
2018 ◽  
Vol 4 (1) ◽  
pp. 14 ◽  
Author(s):  
Sylvain Mogliacci ◽  
Isobel Kolbé ◽  
W. Horowitz
Keyword(s):  
Equation Of State ◽  
Degrees Of Freedom ◽  
Compact Star ◽  
Relativistic Quantum ◽  
Finite Size ◽  
Baryon Number ◽  
System Size ◽  
Heavy Ion ◽  
Compact Stars ◽  
Heavy Ion Physics

In this article, we start by presenting state-of-the-art methods allowing us to compute moments related to the globally conserved baryon number, by means of first principle resummed perturbative frameworks. We focus on such quantities for they convey important properties of the finite temperature and density equation of state, being particularly sensitive to changes in the degrees of freedom across the quark-hadron phase transition. We thus present various number susceptibilities along with the corresponding results as obtained by lattice quantum chromodynamics collaborations, and comment on their comparison. Next, omitting the importance of coupling corrections and considering a zero-density toy model for the sake of argument, we focus on corrections due to the small size of heavy-ion collision systems, by means of spatial compactifications. Briefly motivating the relevance of finite size effects in heavy-ion physics, in opposition to the compact star physics, we present a few preliminary thermodynamic results together with the speed of sound for certain finite size relativistic quantum systems at very high temperature.

scholarly journals Hadron resonance gas with van der Waals interactions

2020 ◽  
Vol 29 (05) ◽  
pp. 2040002 ◽  
Author(s):  
Volodymyr Vovchenko
Keyword(s):  
Equation Of State ◽  
Van Der Waals ◽  
Heavy Ion ◽  
Van Der Waals Interactions ◽  
Excluded Volume ◽  
Heavy Ion Collision ◽  
Lattice Quantum Chromodynamics ◽  
Qcd Critical Point ◽  
Lattice Quantum ◽  
Ion Collision

An overview of a hadron resonance gas (HRG) model that includes van der Waals (vdW) interactions between hadrons is presented. Applications of the excluded volume HRG model to heavy-ion collision data and lattice quantum chromodynamics (QCD) equation of state are discussed. A recently developed quantum vdW HRG model is covered as well. Applications of this model in the context of the QCD critical point are elaborated.

scholarly journals Influence of the equation of state on a compact star made of hidden-sector nucleons

2020 ◽  
Vol 2020 (3) ◽  
Author(s):  
Shinji Maedan
Keyword(s):  
Equation Of State ◽  
Cold Dark Matter ◽  
Compact Star ◽  
Mean Field ◽  
Field Approximation ◽  
Compact Stars ◽  
Mean Field Approximation ◽  
Effective Theory ◽  
Hidden Sector ◽  
Two Parameters

Abstract We study a compact star made of degenerate hidden-sector nucleons which will be a candidate for cold dark matter. A hidden sector like quantum chromodynamics is considered, and as the low-energy effective theory we take the (hidden-sector) $ SU(2) $ chiral sigma model including a hidden-sector vector meson. With the mean field approximation, we find that one can treat the equation of state (EOS) of our model analytically by introducing a variable which depends on the Fermi momentum. The EOS is specified by the two parameters $ C'_{\sigma} $, $ C'_{\omega} $, and we discuss how these parameters affect the mass–radius relation for a compact star as well as the EOS. The dependence of the maximum stable mass of compact stars on the parameter $ C'_{\sigma} $ will also be discussed.

Covariant Equation of State for Two Colliding Nuclear Matters in the Relativistic Meson Field Theory

1997 ◽  
Vol 06 (01) ◽  
pp. 151-159 ◽  
Author(s):  
M. Rashdan
Keyword(s):  
Field Theory ◽  
Equation Of State ◽  
Nonlinear Models ◽  
Mean Field Theory ◽  
Mean Field ◽  
Heavy Ion ◽  
Ion Scattering ◽  
Relativistic Mean Field ◽  
Heavy Ion Scattering ◽  
Covariant Equation

The relativistic mean field theory (linear and nonlinear) models are extended to the case of two colliding nuclear matters, relevant to heavy ion scattering and reactions. The effect of vacuum corrections is taken into account through the relativistic Hartree approximation. The Fermi sea is assumed to consist of two colliding Lorentz elongated spheres. A relativistic covariant Pauli correction is considered for the overlap case. This relativistic Pauli correction is found to be very important due to its dependence on the effective nucleon mass which strongly depends on the model equation of state. It is found that by increasing the velocity the energy per baryon increases and saturates at higher densities. The increase in the energy per baryon at low density (the region of no overlap) is much larger than that at high density (the region of large overlap), due to Pauli correction effects. The saturation density of the nonlinear model is shifted to larger values than that of the linear model. Vacuum corrections effects are found to reduce largely te overlap region.

Measurement and Modelling of the Radiation Damage of Silicon by MeV Ag Ions

1998 ◽  
Vol 540 ◽  
Author(s):  
Jörg K.N. Lindner ◽  
Johann Eder ◽  
Bernd Stritzker
Keyword(s):  
Radiation Damage ◽  
Depth Profiling ◽  
Heavy Ion ◽  
Model Parameters ◽  
Heavy Ion Collision ◽  
Depth Profiles ◽  
Long Tails ◽  
Ion Collision ◽  
Dose Dependent ◽  
Dependent Point

AbstractDepth profiles of the radiation damage produced by 4 MeV Ag ions in Si(111) at temperatures of 210-450 K are studied by optical reflectivity depth profiling and TEM for doses between 1012 and 1015 Ag/cm2. For high implantation temperatures, the depth of maximum damage is shown to be dose dependent. Point defect diffusion is shown to result in long tails of defect depth profiles. High-temperature amorphization is observed to proceed via the formation and bridge-like coalescence of isolated amorphous volumina. The damage at the depth of the maximum in the nuclear stopping power is described as a function of dose and temperature by the Hecking model. The model parameters and a comparison with those obtained for lighter ions reflect the particular properties of heavy ion collision cascades.

STRONGLY INTERACTING QGP AND QUARKONIUM SUPPRESSION AT RHIC AND LHC ENERGIES

2012 ◽  
Vol 27 (02) ◽  
pp. 1250009 ◽  
Author(s):  
VINEET AGOTIYA ◽  
LATA DEVI ◽  
UTTAM KAKADE ◽  
BINOY KRISHNA PATRA
Keyword(s):  
Equation Of State ◽  
Degrees Of Freedom ◽  
Heavy Ion ◽  
Gluon Plasma ◽  
Relativistic Heavy Ion Collisions ◽  
Strongly Coupled ◽  
Cornell Potential ◽  
Ion Collisions ◽  
Strongly Interacting ◽  
Strongly Coupled Plasma

We have developed an equation of state for strongly interacting quark–gluon plasma (QGP) in the framework of strongly coupled plasma with appropriate modifications to take account of color and flavor degrees of freedom and the interactions among themselves. For this purpose we used the effective potential to improve the plasma parameter (Γ) by correcting the full Cornell potential with a dielectric function embodying the effects of the deconfined medium and not its Coulomb part alone and obtain the equation of state in terms of Γ. Our results on thermodynamic observables viz. pressure, energy density, speed of sound etc. nicely fit to the results of lattice equation of state for gluon, massless as well massive flavored plasma. We have then employed our equation of state to estimate the quarkonium suppression in an expanding QGP produced in the relativistic heavy-ion collisions. We have found that our predictions matches with the recent PHENIX data on the centrality dependence of J/ψ suppression in Au+Au collisions at BNL RHIC within the limit of other uncertainties. We have also predicted for the ϒ suppression in Pb+Pb collisions at LHC energy which could be tested in the ALICE experiments at CERN LHC.

STELLAR STRUCTURE FROM QCD

2012 ◽  
Vol 18 ◽  
pp. 91-95
Author(s):  
BRUNO FRANZON ◽  
F. S. NAVARRA ◽  
DAVID FOGAÇA
Keyword(s):  
Equation Of State ◽  
Quark Gluon Plasma ◽  
Mean Field ◽  
Gluon Plasma ◽  
Field Approximation ◽  
Compact Stars ◽  
Stellar Structure ◽  
Mean Field Approximation

Using an equation of state based on a mean-field approximation for QCD (MQCD) to describe the cold quark gluon plasma we study the stellar structure of compact stars.

scholarly journals The proton mass and scale-invariant hidden local symmetry for compressed baryonic matter

2017 ◽  
Vol 32 (35) ◽  
pp. 1747012 ◽  
Author(s):  
Mannque Rho
Keyword(s):  
Light Quark ◽  
Goldstone Boson ◽  
Local Symmetry ◽  
Heavy Ion ◽  
High Density ◽  
Compact Stars ◽  
Baryonic Matter ◽  
Solar Mass ◽  
Scale Invariant ◽  
Proton Mass

I discuss how to access dense baryonic matter of compact stars by combining hidden local symmetry (HLS) of light-quark vector mesons with spontaneously broken scale invariance of a (pseudo) Nambu–Goldstone boson, dilaton, in a description that parallels the approach to dilatonic Higgs. Some of the surprising observations are that the bulk of proton mass is not Nambu–Goldstonian, parity doubling emerges at high density and the EoS of baryonic matter can be soft enough for heavy-ion processes at low density and stiff enough at high density for [Formula: see text] solar mass neutron stars.

Sign in / Sign up

Export Citation Format

Share Document