Definition: | of a substance, for a parallel beam of specified radiation, the quantity μ in the expression μdх for the fraction of a radiation quantity removed by attenuation in passing through a thin layer dx of that substance. It is a function of the energy of the radiation. According as to whether dx is expressed in terms of length, mass per unit area, moles per unit area, or atoms per unit area μ is called the linear, mass, molar, or atomic attenuation coefficient
|