Pair production

The pair production process is one of the most interesting demonstrations for the presence of space matter in atoms. When higher energy photons (1.022 MeV and above) are passed through near a heavy nucleus (that is, the innermost transitory shells) it can result the production of one electron and one positron. The quantity of space matter that closer to a heavy nucleus is equal to or more than the mass of one electron and one positron, because of its high density. When such energetic gamma ray photons are passed through the high-density space matter region, the individual space matter units will be bonded together to produce the electron-positron pair.