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A deuterium nucleus evolves by the catching of a neutron and proton.What is meant by catching or colliding in the context of upquarks,downquarks and the gluons.
This is a standard low energy nuclear reaction, n + p --> d.+ gamma. The gamma ray has about 2.2 MeV worth of energy, equal to the binding energy of the deuterium system. The constituent quarks of the neutron and of the proton pretty much ignore each other and go about their own business. At much, much higher interaction energies the quarks and gluons might come into play and produce other particles such as pi mesons.
(published on 05/21/09)
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