Nuclear symmetry energy and incompressibility of hot asymmetric nuclear matter in the Thomas-Fermi model

2011 ◽  
Vol 6 (35) ◽  
Author(s):  
S. Mohammadpour Lima
Keyword(s):  
Nuclear Matter ◽  
Symmetry Energy ◽  
Nuclear Symmetry Energy ◽  
Fermi Model ◽  
Asymmetric Nuclear Matter ◽  
Thomas Fermi

scholarly journals On Phase Transitions of Nuclear Matter in the Nambu-Jona-Lasinio Model

2011 ◽  
Vol 21 (2) ◽  
pp. 117
Author(s):  
Tran Huu Phat ◽  
Le Viet Hoa ◽  
Nguyen Van Long ◽  
Nguyen Tuan Anh ◽  
Nguyen Van Thuan
Keyword(s):  
Phase Transitions ◽  
Nuclear Matter ◽  
Density Dependence ◽  
Symmetry Energy ◽  
Nuclear Symmetry Energy ◽  
Double Bubble ◽  
Bulk Properties ◽  
Asymmetric Nuclear Matter ◽  
Njl Model ◽  
Good Agreement

Within the Cornwall - Jackiw - Tomboulis (CJT) approach a general formalism is established for the study of asymmetric nuclear matter (ANM) described by the Nambu-Jona-Lasinio (NJL) model. Restricting to the double-bubble approximation (DBA)we determine the bulk properties of ANM, in particular, the density dependence of the nuclear symmetry energy, which is in good agreement with data of recent analyses.

scholarly journals Nuclear Symmetry Energy in Chiral Model of Nuclear Matter

2012 ◽  
Vol 22 (2) ◽  
pp. 183
Author(s):  
Nguyen Tuan Anh ◽  
Tran Huu Phat ◽  
Dinh Thanh Tam
Keyword(s):  
Physical Properties ◽  
Nuclear Matter ◽  
Density Dependence ◽  
Symmetry Energy ◽  
Degrees Of Freedom ◽  
Chiral Model ◽  
Nuclear Symmetry Energy ◽  
Asymmetric Nuclear Matter ◽  
Good Agreement

The physical properties of asymmetric nuclear matter are studied in the Extended Nambou-Jona-Lasinio (ENJL) model formulated directly in the nucleon degrees of freedom. It results that the density dependence of the nuclear symmetry energy and its related quantities are basically in good agreement with data of recent analyses.

scholarly journals ISOSPIN AND DENSITY DEPENDENCIES OF NUCLEAR MATTER SYMMETRY ENERGY COEFFICIENTS

2003 ◽  
Vol 12 (06) ◽  
pp. 755-770 ◽  
Author(s):  
FÁBIO L. BRAGHIN
Keyword(s):  
Nuclear Matter ◽  
Symmetry Energy ◽  
Heavy Ions ◽  
High Energy ◽  
Asymmetry Coefficient ◽  
Asymmetric Nuclear Matter ◽  
Common Features ◽  
Astrophysical Objects ◽  
Alternative Behaviors ◽  
Analytical Expressions

Symmetry energy coefficients of explicitly isospin asymmetric nuclear matter at variable densities (from 0.5ρ0 up to 2ρ0) are studied as generalized screening functions. An extended stability condition for asymmetric nuclear matter is proposed. We find the possibility of obtaining stable asymmetric nuclear matter even in some cases for which the symmetric nuclear matter limit is unstable. Skyrme-type forces are extensively used in analytical expressions of the symmetry energy coefficients derived as generalized screening functions in the four channels of the particle hole interaction producing alternative behaviors at different ρ and b (respectively, the density and the asymmetry coefficient). The spin and spin-isospin coefficients, with corrections to the usual Landau Migdal parameters, indicate the possibility of occurring instabilities with common features depending on the nuclear density and n–p asymmetry. Possible relevance for high energy heavy ions collisions and astrophysical objects is discussed.

Equilibrium theory of the nuclear symmetry energy of infinite nuclear matter

1969 ◽  
Vol 47 (20) ◽  
pp. 2171-2209 ◽  
Author(s):  
Richard A. Weiss ◽  
A. G. W. Cameron
Keyword(s):  
Kinetic Energy ◽  
Nuclear Matter ◽  
Symmetry Energy ◽  
Density Variation ◽  
Average Kinetic Energy ◽  
Constant Density ◽  
Nuclear Symmetry Energy ◽  
Neutron Excess ◽  
Order Coefficient ◽  
Excess Parameter

A set of generalized nuclear matter curves is calculated as a function of density and ξ = 1−(2Z/A), which maps out the energy versus density plane for 0 ≤ ξ ≤ 1 and determines the nuclear matter equilibrium curve (NMEC) as the locus of their saturation points. The NMEC immediately determines the equilibrium energy and density as a function of the neutron excess, and thereby automatically gives the nuclear symmetry energy. The component parts of the equilibrium energy are also determined, and we find that the average kinetic energy per nucleon is a decreasing function of the neutron excess parameter, so that the contribution of the kinetic energy to the second order coefficient, β2∞, is negative. By noting that the density variation along the NMEC is determined by kFE = k∞(1−F2ξ2 + F4ξ4−… ) f−1 with k∞ = 1.4 f−1, F2 ~ 0.45, and F4 ~ 0.07, we find a general connection between the equilibrium and nonequilibrium symmetry energy coefficients, i.e. β0∞ = β0NE(k∞), β2∞ = β2NE(k∞), β4∞ = β4NE(k∞)[Formula: see text], etc., where K0(2) is the standard nuclear compressibility. We find a large negative value for the fourth order coefficient, β4∞ ~ −25 MeV, and a large positive value for the sixth order coefficient, β6∞ ~ 15 MeV, while the corresponding nonequilibrium values of these two coefficients are small and positive. Nuclear matter systems with neutron excess are found to be more bound than is predicted by constant density calculations, and we find that a negative isospin compression energy term is required to be added to the previous constant density calculations.

ISOSPIN DEPENDENCE OF THE SATURATION PROPERTIES OF ASYMMETRIC NUCLEAR MATTER IN NONRELATIVISTIC MEAN FIELD MODEL

2012 ◽  
Vol 21 (09) ◽  
pp. 1250079 ◽  
Author(s):  
S. CHAKRABORTY ◽  
B. SAHOO ◽  
S. SAHOO
Keyword(s):  
Nuclear Matter ◽  
Fourth Order ◽  
Symmetry Energy ◽  
Mean Field ◽  
Saturation Density ◽  
Order Effects ◽  
Mean Field Model ◽  
Isospin Asymmetry ◽  
Asymmetric Nuclear Matter ◽  
Isospin Dependence

A phenomenological momentum dependent interaction (MDI) is considered to describe the equation of state (EOS) for isospin asymmetric nuclear matter (ANM), where the density dependence of the nuclear symmetry is the basic input. In this interaction, the symmetry energy shows soft dependence of density. Within the nonrelativistic mean field approach we calculate the nuclear matter fourth-order symmetry energy E sym, 4 (ρ). Our result shows that the value of E sym, 4 (ρ) at normal nuclear matter density ρ0( = 0.161 fm -3) is less than 1 MeV conforming the empirical parabolic approximation to the EOS of ANM at ρ0. Then the higher-order effects of the isospin asymmetry on the saturation density ρ sat (β), binding energy per nucleon K sat (β) and isobaric incompressibility K sat (β) of ANM is being studied, where [Formula: see text] is the isospin asymmetry. We have found that the fourth-order isospin asymmetry β cannot be neglected, while calculating these quantities. Hence the second-order K sat , 2 parameter basically characterizes the isospin dependence of the incompressibility of ANM at saturation density.

scholarly journals A Modern View of the Equation of State in Nuclear and Neutron Star Matter

Symmetry ◽  
2021 ◽  
Vol 13 (3) ◽  
pp. 400
Author(s):  
G. Fiorella Burgio ◽  
Hans-Josef Schulze ◽  
Isaac Vidaña ◽  
Jin-Biao Wei
Keyword(s):  
Neutron Star ◽  
Equation Of State ◽  
Nuclear Matter ◽  
Symmetry Energy ◽  
Quantum Monte Carlo ◽  
Mean Field ◽  
Nuclear Symmetry Energy ◽  
Relativistic Mean Field ◽  
Monte Carlo Techniques ◽  
Nuclear Incompressibility

Background: We analyze several constraints on the nuclear equation of state (EOS) currently available from neutron star (NS) observations and laboratory experiments and study the existence of possible correlations among properties of nuclear matter at saturation density with NS observables. Methods: We use a set of different models that include several phenomenological EOSs based on Skyrme and relativistic mean field models as well as microscopic calculations based on different many-body approaches, i.e., the (Dirac–)Brueckner–Hartree–Fock theories, Quantum Monte Carlo techniques, and the variational method. Results: We find that almost all the models considered are compatible with the laboratory constraints of the nuclear matter properties as well as with the largest NS mass observed up to now, 2.14−0.09+0.10M⊙ for the object PSR J0740+6620, and with the upper limit of the maximum mass of about 2.3–2.5M⊙ deduced from the analysis of the GW170817 NS merger event. Conclusion: Our study shows that whereas no correlation exists between the tidal deformability and the value of the nuclear symmetry energy at saturation for any value of the NS mass, very weak correlations seem to exist with the derivative of the nuclear symmetry energy and with the nuclear incompressibility.

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