Surface structure of deformed nuclei by radical and angular localization in heavy-ion scattering

Theoretical and experimental methods for studying heavy-ion inelastic scattering from deformed nuclei are described. The theoretical methods involve classical-limit approximations, while particle-γ-ray spectroscopy techniques are employed experimentally. With these approaches, heavy-ion excitation in the Coulomb-nuclear interference region acquires a transparent interpretation, despite the apparent complexity of the multistep excitation processes involved. Radial and angular localization effects in such collisions are discussed. The sensitivity of the inelastic scattering to details of the surface ion-ion potential due to radial and angular localization is exploited to introduce a method of determining the equipotential contours in a direct manner which bypasses particular model-dependent parametrizations. Adiabatic giant resonance polarization potentials are included explicitly in the prescription.

Experimental inelastic excitation functions for the scattering of ⁴⁰Ar projectiles from ¹⁵⁶Gd, ¹⁶⁰Gd, ¹⁶²Dy, ¹⁶⁴Dy, and ¹⁸⁰Hf are reported. Ion-ion potential contours for these systems are obtained with the aforementioned method. These contours agree well with calculations which employ deformed double-folding potentials and deformed proximity potentials. Electric quadrupole and hexadecapole moments deduced for ¹⁸⁰Hf disagree with previous Coulomb-excitation measurements with α-particle projectiles.

The examples discussed provide a good illustration of the relationship between classical and quantum physics. The general nature of the localization effects for any system which has dynamical variables which take on large quantum numbers is emphasized.