Surface Symmetry Energy of Nuclear Energy Density Functionals

The thesis studies the bulk deformation properties of the Skyrme nuclear energy density
functionals. Following simple arguments based on the leptodermous expansion and
liquid drop model, the current research applies the nuclear density functional theory to
assess the role of the surface symmetry energy in nuclei. To this end, one can validate
the commonly used functional parametrizations against the data on excitation energies of
superdeformed band-heads in Hg and Pb isotopes, and fission isomers in actinide nuclei.
After subtracting shell effects, the results of our self-consistent calculations are consistent
with macroscopic arguments and indicate that experimental data on strongly deformed
congurations in neutron-rich nuclei are essential for optimizing future nuclear energy density
functionals. The resulting survey provides a useful benchmark for further theoretical
improvements. Unlike in nuclei close to the stability valley, whose macroscopic deformability
hangs on the balance of surface and Coulomb terms, the deformability of neutron-rich
nuclei strongly depends on the surface-symmetry energy; hence, its proper determination
is crucial for the stability of deformed phases of the neutron-rich matter and description
of fission rates for r-process nucleosynthesis. The results and consequent discussions from
the thesis were published in Ref. [134].