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physical phenomena > process > physical process > optical process > radiation modification > radiation intensity modification > absorption

absorption
subject			fact

absorption	has inverse process emission
	has definition Decrease in the intensity of radiation, representing energy converted into excitation or ionization of electrons in the region through which the radiation travels. As contrasted with monochromatic scattering (in which reemission occurs in all directions at the same frequency), the inverse process of emission refers to radiation that is reemitted in general in all directions and at all frequencies.
	is a kind of radiation intensity modification
radiation intensity modification	changes property intensity
optical process	has domain optics

Kinds of absorption :

• attenuation (2 facts) - The falling off of the energy density of radiation with distance from the source, or with passage through an absorbing or scattering medium.
• inverse bremsstrahlung (4 facts) - Absorption of a photon by an electron in the field of a nucleus.
• selective absorption (1 kind, 6 facts) (reddening) - The reddening of starlight in passing through fine particles of interstellar dust., The process by which light from an astronomical object grows red as the light travels through interstellar dust. Dust scatters blue light more than red, thus leaving predominantly red light transmitted.