Evolution of the symmetry energy of hot neutron-rich matter formed in heavy-ion reactions

Abstract

It is shown that the experimentally observed decrease of the nuclear symmetry energy with the increasing centrality or the excitation energy in isotopic scaling analyses of heavy-ion reactions can be well understood analytically within a degenerate Fermi gas model. The evolution of the symmetry energy is found to be mainly due to the variation in the freeze-out density rather than temperature. The isoscaling analyses are useful for probing the interaction part of the nuclear symmetry energy, provided that both the freeze-out temperature and density of the fragments can be inferred simultaneously from the experiments.

6 pages, 2 figures. Title changed little, comments on extracting the symmetry energy from the isoscaling phenomenon are added. Revised version to appear in PRC

References in corpus (3)

• Neutron-Rich Nuclei in Heaven and Earth
• Isospin Diffusion in Heavy-Ion Collisions and the Neutron Skin Thickness of Lead
• Temperature dependence of single-particle properties in nuclear matter

Cited by in corpus (17)

• Isospin dependent multifragmentation of relativistic projectiles
• Temperature effects on the nuclear symmetry energy and symmetry free energy with an isospin and momentum dependent interaction
• Effects of isospin and momentum dependent interactions on thermal properties of asymmetric nuclear matter
• Thermal effects on nuclear symmetry energy with a momentum-dependent effective interaction
• Isoscaling as a measure of Symmetry Energy in the Lattice Gas Model
• Temperature dependence of the symmetry energy and neutron skins in Ni, Sn, and Pb isotopic chains
• Temperature and momentum dependence of single-particle properties in hot asymmetric nuclear matter
• Isospin dependent thermodynamics of fragmentation
• N/Z Dependence of Projectile Fragmentation
• Isospin effect in the statistical sequential decay
• Density dependence of symmetry free energy of hot nuclei
• Temperature effects in the nuclear isoscaling
• Isoscaling, Symmetry Energy and Thermodynamic Models
• The role of bulk energy in nuclear multifragmentation
• Density dependence of the "symmetry energy" in the lattice gas model
• Isoscaling in statistical fragment emission in an extended compound nucleus model
• Isobar correlations bearing information on the properties of hot disassembling nuclear sources