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physical phenomena > event > atomic process > ionization

ionization
subject			fact

ionization	has antonym recombination
	has definition Loss or gain by an atom of one or more electrons, by which process the atom becomes an ion and instead of being neutral, has a charge: positive if it has lost an electron, negative if it has gained one. High temperature is particularly conducive to ionization.
	is a kind of atomic process
atomic process	has domain atomic physics
event	has duration
	has synonym world point
	has time of occurrence

Kinds of ionization :

• Auger transition (1 kind, 4 facts) - A radiationless quantum jump that occurs in the X-ray region. When a K-electron is removed from an atom and an L-electron drops into the vacancy in the K-shell, the energy released in the latter transition goes not into radiation, but into the liberation of one of the remaining L-electrons.
• autoionization (3 facts) - A phenomenon occurring when a discrete double-excitation state of an atom lies in the ground-state continuum. In the autoionization process one of the excited electrons is ejected, leaving the ion in an excited state (see dielectronic recombination; see also Auger effect). (also called pre-ionization)
• photoionization (2 facts) - The ionization of an atom or molecule by the absorption of a high-energy photon by the particle. It is an important source of opacity in stars.
• pressure ionization (2 facts) - A state found in white dwarfs and other degenerate matter in which the atoms are packed so tightly that the electron orbits encroach on each other to the point where an electron can no longer be regarded as belonging to any particular nucleus and must be considered free.