Question

Compare and contrast the Fermi and Shell models for the nucleus.

Answer 1

In the Fermi model protons and neutrons are considered as moving freely. It treats nucleus as a liquid. The nuclear potential well is considered as rectangular. The potential is constant inside the nucleus and stops sharply at its edge. The protons and neutron have two separated well. this model gives rise to semi-empirical binding energy formula.

while in shell model more realistic potential is considered for the nucleus and the energy of states is obtained. the nucleus can be seen in terms of orbits and shell. the nucleons fill each energy state with nucleon with definite angular momentum.