EMC effect

The EMC effect in nuclear and particle physics is the dependence of the structure functions of the nucleons of the core environment. He was appointed to the European Muon Collaboration ( EMC ), 1983 he was discovered at CERN.

In the deep inelastic scattering of electrons, muons and neutrinos protons and neutrons whose structure functions are measured, in turn, provide information about their internal structure. Since this occurs at very high energy and momentum transfers, far higher than the binding energy of atomic nuclei, one had expected that it does not matter whether these particles are free or components of atomic nuclei are - apart from kinematic effects due to the Fermibewegung. In fact, there was a significant deviation in the region of small momentum fractions up to -20 % showed.

There are different approaches to explain this effect: the interaction of quarks via Nukleongrenzen of time, partial absorption of the interacting virtual photon ( shadowing ) by the fluctuation in virtual hadrons, the formation of multi- quark clusters and others. A generally accepted explanation is still pending.