annihilation(redirected from Exnihilation)
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annihilationA reaction between an elementary particle and its antiparticle in which the two particles disappear and photons or other particles and antiparticles are created; energy and momentum are conserved. An electron and a positron, for example, interact and produce two gamma-ray photons. Hadrons, such as the proton and the antiproton, also undergo annihilation, as do quarks and antiquarks.
A process in which an antiparticle and a particle combine and release their rest energies in other particles.