Time-Dependent Statistical Mechanics 16. Scattering of particles and radiation by macroscopic systems
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چکیده
Many scattering experiments in which a beam radiation or particles are sent into a material that scatters them have a number of features in common. (We shall use the word radiation to refer to the thing that is scattered.) • The radiation is a wave that satisfies a wave equation. • The incident beam is collimated (moving in one particular direction). • The incident beam is monochromatic (a narrow range of frequencies and energies). • The radiation interacts weakly with the sample and only a small fraction of the radiation is scattered. Most of the scattered radiation leaves the sample without being scattered again. • The detector is shielded so that it detects only that radiation coming out in a narrow range of directions. This applies to • scattering of electromagnetic radiation, including – visible light
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