Nuclear Sizes and Shapes
Friday, April 1, 2022
The density of a nucleus is fairly constant (it does not increase in density drastically towards the center). Additionally, the density at the center of the nucleus is not correlated with mass number ; atoms tend to have approximately the same density:
Assuming the nucleus is a sphere of radius , the constant of proportionality is therefore defined as
Experimentally, this value is found to be approximately .
The size of the nucleus can be measured using Rutherford scattering, where alpha particles are sent into atoms. If the alpha particle is outside the nucleus, the Rutherford scattering formula is relatively accurate, however, it begins to deviate when the closest approach is less than the nuclear radius.