Auger effect

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Auger effect

One of the two principal processes for the relaxation of an inner-shell electron vacancy in an excited or ionized atom. The Auger effect is a two-electron process in which an electron makes a discrete transition from a less bound shell to the vacant, but more tightly bound, electron shell. The energy gained in this process is transferred, via the electrostatic interaction, to another bound electron which then escapes from the atom. This outgoing electron is referred to as an Auger electron and is labeled by letters corresponding to the atomic shells involved in the process. For example, a KLILIII Auger electron corresponds to a process in which an LI electron makes a transition to the K shell and the energy is transferred to an LIII electron (illus. a). By the conservation of energy, the Auger electron kinetic energy E is given by E = E(K) - E(LI) - E(LIII) where E(K,L) is the binding energy of the various electron shells. Since the energy levels of atoms are discrete and well understood, the Auger energy is a signature of the emitting atom. See Electron configuration, Energy level (quantum mechanics)

The other principal process for the filling of an inner-shell hole is a radiative one in which the transition energy is carried off by a photon (illus. b). Inner-shell vacancies in elements with large atomic number correspond to large transition energies and usually decay by such radiative processes; vacancies in elements with low atomic number or outer-shell vacancies with low transition energies decay primarily by Auger processes.

Two principal processes for the filling of an inner-shell electron vacancyenlarge picture
Two principal processes for the filling of an inner-shell electron vacancy

Auger effect

[ō′zhā i‚fekt]
(atomic physics)
A two-electron process in which an electron makes a discrete transition from a less bound shell to a vacant electron shell and the energy gained in this process is tranferred via the electrostatic interaction to another bound electron which escapes the atom. Also known as Auger transition; internal absorption; internal photoionization.
References in periodicals archive ?
Detection of the Auger electrons is difficult as scattered primary electrons from the excitation source contribute to a large background in the spectrum.
Analysis of Materials by Electron-Excited Auger Electrons," J.
This article provides an overview of the Auger electron spectroscopy technique and includes examples of its use for studying coatings.
Auger electron spectroscopy (AES) is a surface sensitive analysis method for determining the elemental composition of solid materials.
By building a novel instrument capable of measuring Auger electrons from any angular perspective, the Cincinnati chemists say they have uncovered a more likely origin for the angular distribution of Auger electrons.
They used ADAM to map the angular distribution of silver's Auger electrons.
He says the silhouette interpretation flies in the face of several independent quantum mechanical explanations of the distribution of Auger electrons.
s materials laboratory adjusts the Auger electron energy spectrometer (C) in the whole-disk analyzer.