Nuclear binding energy Only under conditions of extreme pressure and temperature (for example, within the core of a star), can such a process take place. There are around 94 naturally occurring elements on earth. The atoms of each element have a nucleus containing a specific number of protons (always the same number for a given element), and some number of neutrons, which is often roughly a similar number. Two atoms of the same element having different numbers of neutrons are known as isotopes of the element. Different isotopes may have different properties - for example one might be stable and another might be
EMC effect EMC effect The EMC effect is the surprising observation that the cross section for deep inelastic scattering from an atomic nucleus is different from that of the same number of free protons and neutrons (collectively referred to as nucleons). From this observation, it can be inferred that the quark momentum distributions in nucleons bound inside nuclei are different from those of free nucleons. This effect was first observed in 1983 at CERN by the European Muon Collaboration, hence the name "EMC effect". It was unexpected, since the average binding energy of protons and neutrons inside nuclei is insignificant when compared