scholarly journals Analytical relations between nuclear symmetry energy and single-nucleon potentials in isospin asymmetric nuclear matter

2011 ◽  
Vol 865 (1) ◽  
pp. 1-16 ◽  
Author(s):  
Chang Xu ◽  
Bao-An Li ◽  
Lie-Wen Chen ◽  
Che Ming Ko
2011 ◽  
Vol 21 (2) ◽  
pp. 117
Author(s):  
Tran Huu Phat ◽  
Le Viet Hoa ◽  
Nguyen Van Long ◽  
Nguyen Tuan Anh ◽  
Nguyen Van Thuan

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.


2012 ◽  
Vol 22 (2) ◽  
pp. 183
Author(s):  
Nguyen Tuan Anh ◽  
Tran Huu Phat ◽  
Dinh Thanh Tam

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.


2003 ◽  
Vol 12 (06) ◽  
pp. 755-770 ◽  
Author(s):  
FÁBIO L. BRAGHIN

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.


1969 ◽  
Vol 47 (20) ◽  
pp. 2171-2209 ◽  
Author(s):  
Richard A. Weiss ◽  
A. G. W. Cameron

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.


2012 ◽  
Vol 21 (09) ◽  
pp. 1250079 ◽  
Author(s):  
S. CHAKRABORTY ◽  
B. SAHOO ◽  
S. SAHOO

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.


Sign in / Sign up

Export Citation Format

Share Document