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physical phenomena > event > atomic process > collision > scattering

scattering
subject			fact

scattering	has definition Collision between a photon and a particle
	has definition The process whereby light is absorbed and reemitted in all directions, with essentially no change in frequency. Scattering by free electrons was the dominant source of opacity in the early universe.
	is a kind of collision
	is a kind of radiation direction modification
radiation direction modification	changes property direction
atomic process	has domain atomic physics
event	has duration
	has synonym world point
	has time of occurrence

Kinds of scattering :

• backscatter (1 kind, 7 facts) - Scattering of radiation (or particles) through angles greater than 90° with respect to the original direction of motion.
• Brillouin scattering (2 facts) - Slight changes in the frequency of radiation, caused by reflection or scattering from the high-frequency sound waves that arise from thermal vibrations of atoms in the medium.
• coherent scattering (2 facts) - A scattering process that leaves atoms in the same energy state after the scattered photon departs in a direction different from that of the incident photon. The energy of the scattered photon is the same (in the rest frame of the atom) as that of the incident photon.
• Compton scattering (2 kinds, 9 facts) - Decrease in the frequency of high-energy radiation (such as X-rays) caused when a photon loses some of its energy to a free electron by collision., The scattering of photons by free electrons in an ionized medium., Scattering of a photon due to the Compton effect (see also noncoherent scattering).
• conservative scattering (2 facts) - Scattering that occurs in the absence of absorption.
• inverse Compton effect (3 facts) - The collision between a photon and an energetic (cosmic-ray) electron, in which some of the energy of the electron is transferred to the photon.
• Mie scattering (2 facts) - Scattering of light (without regard to wavelength) by larger particles, such as those of dust or fog in Earth's atmosphere.
• non-coherent scattering (2 facts) - Absorption of a photon and reemission at a different frequency (as seen by an observer) by scattering atoms. The natural width of the lines, Doppler broadening, and pressure broadening are the main processes that give rise to noncoherent scattering.
• Raman effect (3 facts) - In spectroscopy, the change in the wavelength of light scattered by molecules., The change of wavelength on scattering. It arises from radiation exciting (or de-exciting) atoms or molecules from their initial states.
• Rayleigh scattering (2 facts) - Selective scattering (i.e., preferential scattering of shorter wavelengths) of light by very small particles suspended in the Earth's atmosphere, or by molecules of the air itself. The scattering is inversely proportional to the fourth power of the wavelength.
• Rocard scattering (2 facts) - Linearly anisotropic scattering.
• Umklapp scattering (2 facts) - The contribution to scattering caused when the exchange of momentum crosses the boundary of a Brillouin zone.
• Zodiacal Light (2 facts) - A faint glow that extends away from the Sun in the ecliptic plane of the sky, visible to the naked eye in the western sky shortly after sunset or in the eastern sky shortly before sunrise. Its spectrum indicates it to be sunlight scattered by interplanetary dust. (Pioneer 10 has determined that its brightness varies inversely as the square of the distance out to 2.25 AU and then decreases more rapidly.) The zodiacal light contributes about a third of the total light in the sky on a moonless night.