Nuclear charge and mass distribution

The distribution of neutrons and protons in a nucleus can be different. In the majority of experiments, a nucleus behaves as a system possessing a center of symmetry and axis of symmetry of an endless order. Consequently, a nucleus also possesses a mirror plane of symmetry perpendicular to the symmetry axis passing through the center of symmetry. 

The charge distribution can be described by the function of the charge density p(x,y,z). The normalization of the charge to the total nuclear charge gives  

The distinctive features can be mentioned in this description. Firstly, the average density function can differ for charge and mass distribution. If, in particular, protons are distributed at the nucleus periphery and neutrons are concentrated nearer the origin, the characteristic radii of the two can be different. They can differ even for the two energy states of one and the same nucleus. Secondly, the unclear forces are of short-range nature. Therefore, nuclei are sharply outlined in space. There is an empirical expression for spheri cal nuclei size  

---

Nud Phys A 597 188 Wahl AC (1988) At Data Nucl Data Tables 39 1 Wahl AC (1989) Nuclear charge and mass distributions from fission. In Behrens JW, Carlson AD (eds) Fifty... 

---