![]() Compton's experiment convinced physicists that light can be treated as a stream of particle-like objects (quanta called photons), whose energy is proportional to the light wave's frequency.Īs shown in Fig. the comment below on elastic scattering of X-rays being from that effect). Or the assumption that the electron can be treated as free is invalid resulting in the effectively infinite electron mass equal to the nuclear mass (see e.g. Thus, if we are to explain low-intensity Compton scattering, light must behave as if it consists of particles. Thomson scattering, the classical theory of an electromagnetic wave scattered by charged particles, cannot explain shifts in wavelength at low intensity: classically, light of sufficient intensity for the electric field to accelerate a charged particle to a relativistic speed will cause radiation-pressure recoil and an associated Doppler shift of the scattered light, but the effect would become arbitrarily small at sufficiently low light intensities regardless of wavelength. The effect is significant because it demonstrates that light cannot be explained purely as a wave phenomenon. Compton was awarded the 1927 Nobel Prize in Physics for the discovery. ![]() Louis and further verified by his graduate student Y. The Compton effect was observed by Arthur Holly Compton in 1923 at Washington University in St. Although nucleus Compton scattering exists, Compton scattering usually refers to the interaction involving only the electrons of an atom. The amount by which the light's wavelength changes is called the Compton shift. 1), the energy of the X ray photon (≈17 keV) was significantly larger than the binding energy of the atomic electron, so the electrons could be treated as being free after scattering. In Compton's original experiment (see Fig. Whether Compton scattering is considered elastic or inelastic depends on the specific definition of these terms being used. From this perspective, Compton scattering could be considered elastic because the internal state of the electron does not change during the scattering process. The electron gains no internal energy, respective masses remain the same, the mark of an elastic collision. Energy of the incident photon is transferred to the electron (recoil) but only as kinetic energy in the laboratory frame. The energy of a scattered photon is measured using Bragg scattering in the crystal on the right in conjunction with ionization chamber the chamber could measure total energy deposited over time, not the energy of single scattered photons.Ĭompton scattering is commonly described as inelastic scattering, because the energy in the scattered photon is less than the energy of the incident photon. The slit passes X-ray photons scattered at a selected angle. ![]() Compton scattering occurs in the graphite target on the left. ![]() 1: Schematic diagram of Compton's experiment. Inverse Compton scattering has the opposite effect, occurring when a high-energy charged particle transfers part of its energy to a photon, resulting in an increase in energy (decrease in wavelength) of the photon. Part of the energy of the photon is transferred to the recoiling particle. It results in a decrease in energy (increase in wavelength) of the photon (which may be an X-ray or gamma ray photon), called the Compton effect. ![]() Compton scattering (also called the Compton effect) discovered by Arthur Holly Compton, is the scattering of a high frequency photon after an interaction with a charged particle, usually an electron. ![]()
0 Comments
Leave a Reply. |
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |