Symmetry Energy in the Equation of State of Asymmetric Nuclear Matter
Abstract
The symmetry energy is an important quantity in the equation of state of isospin asymmetric nuclear matter. This currently unknown quantity is key to understanding the structure of systems as diverse as the neutronrich nuclei and neutron stars. At TAMU, we have carried out studies, aimed at understanding the symmetry energy, in a variety of reactions such as, the multifragmentation of 40Ar, 40Ca + 58Fe, 58Ni and 58Ni, 58Fe + 58Ni, 58Fe reactions at 25  53 AMeV, and deepinelastic reactions of 86Kr + 124,112Sn, 64,58Ni (25 AMeV), 64Ni + 64,58Ni, 112,124Sn, 232Th, 208Pb (25 AMeV) and 136Xe + 64,58Ni, 112,124Sn, 232Th, 197Au (20 AMeV). Here we present an overview of some of the results obtained from these studies. The results are analyzed within the framework of statistical and dynamical models, and have important implications for future experiments using beams of neutronrich nuclei.
 Authors:
 Cyclotron Institute, Texas A and M University, College Station, TX 77843 (United States)
 Publication Date:
 OSTI Identifier:
 21054840
 Resource Type:
 Journal Article
 Resource Relation:
 Journal Name: AIP Conference Proceedings; Journal Volume: 884; Journal Issue: 1; Conference: 6. Latin American symposium on nuclear physics and applications, Iguazu (Argentina), 37 Oct 2005; Other Information: DOI: 10.1063/1.2710604; (c) 2007 American Institute of Physics; Country of input: International Atomic Energy Agency (IAEA)
 Country of Publication:
 United States
 Language:
 English
 Subject:
 73 NUCLEAR PHYSICS AND RADIATION PHYSICS; ARGON 40; ASYMMETRY; CALCIUM 40; DEEP INELASTIC HEAVY ION REACTIONS; EQUATIONS OF STATE; GOLD 197; IRON 58; ISOSPIN; KRYPTON 86; LEAD 208; NEUTRON STARS; NEUTRONRICH ISOTOPES; NICKEL 58; NICKEL 64; NUCLEAR FRAGMENTATION; NUCLEAR MATTER; STATISTICAL MODELS; SYMMETRY; THORIUM 232; XENON 136
Citation Formats
Yennello, S. J., Shetty, D. V., and Souliotis, G. A. Symmetry Energy in the Equation of State of Asymmetric Nuclear Matter. United States: N. p., 2007.
Web. doi:10.1063/1.2710604.
Yennello, S. J., Shetty, D. V., & Souliotis, G. A. Symmetry Energy in the Equation of State of Asymmetric Nuclear Matter. United States. doi:10.1063/1.2710604.
Yennello, S. J., Shetty, D. V., and Souliotis, G. A. Mon .
"Symmetry Energy in the Equation of State of Asymmetric Nuclear Matter". United States.
doi:10.1063/1.2710604.
@article{osti_21054840,
title = {Symmetry Energy in the Equation of State of Asymmetric Nuclear Matter},
author = {Yennello, S. J. and Shetty, D. V. and Souliotis, G. A.},
abstractNote = {The symmetry energy is an important quantity in the equation of state of isospin asymmetric nuclear matter. This currently unknown quantity is key to understanding the structure of systems as diverse as the neutronrich nuclei and neutron stars. At TAMU, we have carried out studies, aimed at understanding the symmetry energy, in a variety of reactions such as, the multifragmentation of 40Ar, 40Ca + 58Fe, 58Ni and 58Ni, 58Fe + 58Ni, 58Fe reactions at 25  53 AMeV, and deepinelastic reactions of 86Kr + 124,112Sn, 64,58Ni (25 AMeV), 64Ni + 64,58Ni, 112,124Sn, 232Th, 208Pb (25 AMeV) and 136Xe + 64,58Ni, 112,124Sn, 232Th, 197Au (20 AMeV). Here we present an overview of some of the results obtained from these studies. The results are analyzed within the framework of statistical and dynamical models, and have important implications for future experiments using beams of neutronrich nuclei.},
doi = {10.1063/1.2710604},
journal = {AIP Conference Proceedings},
number = 1,
volume = 884,
place = {United States},
year = {Mon Feb 12 00:00:00 EST 2007},
month = {Mon Feb 12 00:00:00 EST 2007}
}

The density dependence of the symmetry energy in the equation of state of isospin asymmetric nuclear matter is studied using the isoscaling of the fragment yields and the antisymmetrized molecular dynamic calculation. It is observed that the experimental data at low densities are consistent with the form of symmetry energy, E{sub sym}{approx_equal}31.6({rho}/{rho}{sub circle}){sup 0.69}, in close agreement with those predicted by the results of variational manybody calculation. A comparison of the present result with those reported recently using the NSCLMSU data suggests that the heavy ion studies favor a dependence of the form, E{sub sym}{approx_equal}31.6({rho}/{rho}{sub circle}){sup {gamma}}, where {gamma}=0.61.05. Thismore »

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