Abstract
The symmetry energy of a nucleus is determined in a local density approximation and integrating over the entire density distribution of the nucleus, calculated utilizing the relativistic density-dependent Thomas-Fermi approach. The symmetry energy is found to decrease with increasing neutron excess in the nucleus. The isovector coupling channel reduces the symmetry energy, and this effect increases with increased neutron excess. The isovector coupling channel increases the symmetry energy integral in \(^{40}\hbox {Ca}\) and reduces it in \(^{48}\hbox {Ca}\), and the interplay between the isovector and the isoscalar channels of the nuclear force explains this isotope effect.
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The author acknowledges support by the Atomic Energy Commission of Syria.
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Haddad, S. Symmetry energy of the nucleus in the relativistic Thomas–Fermi approach with density-dependent parameters. Pramana - J Phys 89, 74 (2017). https://doi.org/10.1007/s12043-017-1477-x
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DOI: https://doi.org/10.1007/s12043-017-1477-x
Keywords
- Symmetry energy of a nucleus
- isovector coupling channel
- relativistic Thomas–Fermi approximation
- lead isotopes
- isotones \(N=126\)
- \(^{40}\)Ca
- \(^{48}\)Ca