The kinetic energy of the ejected photoelectron (E e) is equal to the incident photon energy (hν) minus the binding energy of the photoelectron in its original shell (E b). In this interaction the incident photon completely disappears and an energetic photoelectron is ejected by the atom from one of its bound shells. In the photoelectric effect, a photon undergoes an interaction with an electron which is bound in an atom. Rayleigh scattering Photoelectric Absorption of X-rays Gamma absorption by an atom.The photoelectric absorbtion dominates at low-energies of X-rays, while Compton scattering dominates at higher energies. The strength of these interactions depends on the energy of the X-rays and the elemental composition of the material, but not much on chemical properties, since the X-ray photon energy is much higher than chemical binding energies.

Interaction of X-rays with MatterĪlthough a large number of possible interactions are known, there are three key interaction mechanisms with matter. X-rays can travel thousands of feet in air and can easily pass through the human body. Since the X-rays (especially hard X-rays) are in substance high-energy photons, they are very penetrating matter and are thus biologically hazardous. According to the currently valid definition, X-rays are emitted by electrons outside the nucleus, while gamma rays are emitted by the nucleus. The distinction between X-rays and gamma rays is not so simple and has changed in recent decades. X-ray wavelengths are shorter than those of UV rays and typically longer than those of gamma rays. Most X-rays have a wavelength ranging from 0.01 to 10 nanometers (3×10 16 Hz to 3×10 19 Hz), corresponding to energies in the range 100 eV to 100 keV. Photons are categorized according to the energies from low-energy radio waves and infrared radiation, through visible light, to high-energy X-rays and gamma rays. The radiation frequency is key parameter of all photons, because it determines the energy of a photon. X-rays are high-energy photons with short wavelengths and thus very high frequency. X-rays, also known as X-radiation, refers to electromagnetic radiation (no rest mass, no charge) of high energies.

Intraction subsume main effect