$M_P$ denotes the mass of a proton and $M_n$ that a neutron. A given nucleus, of binding energy $\mathrm{B}$…
$M_P$ denotes the mass of a proton and $M_n$ that a neutron. A given nucleus, of binding energy $\mathrm{B}$, contains $Z$ protons and $N$ neutrons. The mass $M(N, Z)$ of the nucleus is given by $(c$ is the velocity of light):