Symmetry energy, unstable nuclei, and neutron star crusts

Phenomenological approach to inhomogeneous nuclear matter is useful to describe fundamental properties of atomic nuclei and neutron star crusts in terms of the equation of state of uniform nuclear matter. We review a series of researches that we have developed by following this approach. We start with more than 200 equations of state that are consistent with empirical masses and charge radii of stable nuclei and then apply them to describe matter radii and masses of unstable nuclei, proton elastic scattering and total reaction cross sections off unstable nuclei, and nuclei in neutron star crusts including nuclear pasta. We finally discuss the possibility of constraining the density dependence of the symmetry energy from experiments on unstable nuclei and even observations of quasi-periodic oscillations in giant flares of soft gamma-ray repeaters.Comment: 17 pages, 16 figures, to appear in EPJA special volume on symmetry energy. arXiv admin note: text overlap with arXiv:1303.450

The symmetry energy at subnuclear densities and nuclei in neutron star crusts

We examine how the properties of inhomogeneous nuclear matter at subnuclear densities depend on the density dependence of the symmetry energy. Using a macroscopic nuclear model we calculate the size and shape of nuclei in neutron star matter at zero temperature in a way dependent on the density dependence of the symmetry energy. We find that for smaller symmetry energy at subnuclear densities, corresponding to larger density symmetry coefficient L, the charge number of nuclei is smaller, and the critical density at which matter with nuclei or bubbles becomes uniform is lower. The decrease in the charge number is associated with the dependence of the surface tension on the nuclear density and the density of a sea of neutrons, while the decrease in the critical density can be generally understood in terms of proton clustering instability in uniform matter.Comment: 13 pages, 9 figures; Fig. 6 corrected, typos correcte

Synthesis of thin-long heavy nuclei in ternary collisions

We illustrate the formation of a thin-long structure of heavy nuclei by three-nucleus simultaneous collisions within time-dependent density functional theory. The impact parameter dependence for such formation is systematically demonstrated through clarifications of the difference between binary and ternary collision events. A new method for producing thin-long heavy nuclei in the laboratory is suggested, as well as the possible formation of the thin-long structure in hot dense matter such as that encountered in core collapse supernovae.Comment: submitte