pair production

Formation of an electron and a positron from high-energy electromagnetic radiation traveling through matter, usually in the vicinity of an atomic nucleus. It is a direct conversion of radiant energy into matter in accordance with the equation math.E = math.mmath.c², where math.E is the amount of energy, math.m is the mass, and math.c is the speed of light. It is one of the principal ways in which high-energy gamma rays are absorbed in matter. The positrons quickly disappear by being reconverted into photons in the process of annihilation with other electrons. Pair production may sometimes refer to the formation of other particle/antiparticle pairs as well.

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• 2 (number), two of something
• Topological pair, an inclusion of topological spaces.
• Au pair, a work agreement
• Couple, various senses for two joined things
• Even number, in roulette etc.
• Ordered pair, in Mathematics and set theory
• Twisted pair, a couple of electric wires twisted together
• Pair (parliamentary convention), matching of members unable to attend, so as not to change the voting margin
• pair, the French equivalent of peer, holder of a French Pairie, French high title roughly equivalent to a member of the British peerage
• pair, a member of the Prussian House of Lords
• Pair (Cricket): "getting a pair" means being out for 0 in both innings of a match
• A handshaking process in Bluetooth communications
• P_air, Pressure of air in a system

See also

• Pairing
• Pear - fruit
• Pare - Tanzanian ethnic group
• Paired test in statistical hypothesis testing