(AC) The attenuation correction is usually applied to achieve count rate values independent from tissue densities.

A lower orbited electron leaves the atom - the reoccupation of this vacancy by a higher orbited electron leads to the emission of energy which in turn leads to the emission of a second electron, the Auger electron.

See also Auger Electron, Electron Excitation, Megaelectron Volt and Auger Pierre Victor.

The Auger electron is emitted caused by the Auger effect. The kinetic energy of the Auger electron depends on the type of atom and the chemical environment. The energy of the Auger electron is in the range between 280 eV (electron volt) and 2100 eV. These different energy levels are utilized for chemical analysis.

See also Auger Effect, Compton Electron, Conversion Electron, Initiating Electron and Auger Pierre Victor.

Auger, Pierre Victor described for the first time the process of the internal transformation of x-rays in photoelectrons.

See also Auger Effect and Auger Electron.

Autoradiography is a method that uses incorporated radioactive material as the source of the radiation. The image on an x-ray film or nuclear emulsion is recorded by direct contact of the object with photo emulsion. Photographic emulsions have a very high efficiency for beta radiation.