= Nuclear radius scaling
{title2=$R\simeq r_0A^{1/3}$}
The approximate mass-number dependence of a sharp equivalent nuclear radius. Near-constant interior <nucleon> number density gives $A\simeq(4\pi/3)n_0R^3$, hence $R\propto A^{1/3}$. A conventional matter-radius scale is $r_0\simeq1.2\,\mathrm{fm}$, with isotope and definition dependence. A charge-weighted root-mean-square radius is a different observable: for a uniform sphere it is $\sqrt{3/5}R$. Diffuse surfaces and <neutron> skins prevent interpreting the scaling as a universal hard boundary.
Back to article page
