Atomic nucleus

A model o the atomic nucleus shawin it as a compact bundle o the twa kynds o nucleons: protons (reid) an neutrons (blue). In this diagram, protons an neutrons leuk lik smaa baas stuck thegither, but an actual nucleus (as unnerstood bi modren nuclear physics) canna be explained lik this, but anely bi uisin quantum mechanics. In a nucleus that occupies a certain energy level (fur exemple, the grund state), ilk nucleon haes mony locations at ance.

The nucleus is the verra dense region consistin o protons an neutrons at the centre o an atom. It wis discovert in 1911 as a result o Ernest Rutherford's interpretation o the 1909 Geiger–Marsden gowd foil experiment performed bi Hans Geiger an Ernest Marsden unner Rutherford's direction. The proton–neutron model o nucleus wis proponed bi Dmitry Ivanenko in 1932. Aamaist aa o the mass o an atom is locatit in the nucleus, wi a verra smaa contreibution frae the electron clood.