When a beam of monochromatic X-rays(or Gama-rays) is scattered by a light element such as carbon, the scattered radiation in a particular direction consists not only of the unmodified incident primary radiation , as expected classically , but also of another new modified radiation of slightly shorter frequency ( or longer wavelength) ― the satellite line. Scattering with a modified wavelength is called incoherent scattering. This type of incoherent X-ray (or Gamma-ray) scattering is known as the Compton effect.
Characteristics – It is found that the wavelength-shift (also called Compton-shift) between the two radiations ― primary and the satellite ― varies with the angle of scattering but is independent of the wavelength of the primary radiation and also of the nature of the scatterer.
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| Compton effect : Kinetics of Compton scattering |
In Compton effect , the incident radiation is scattered by the free electron at rest. The scattered radiation has longer wavelength compared to incident radiation.
The Big Bang 