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In the professional literature, the effect is often named Radiation Induced Attenuation (RIA), or Radiation-induced darkening. The loss of power or 'darkening' occurs because the chemical bonds forming the optical fiber core are disrupted by the impinging high energy resulting in the appearance of new electronic transition states giving rise to additional absorption in the wavelength regions ...
The scintillator must be shielded from all ambient light so that external photons do not swamp the ionization events caused by incident radiation. To achieve this a thin opaque foil, such as aluminized mylar, is often used, though it must have a low enough mass to minimize undue attenuation of the incident radiation being measured.
Accounting for attenuation effects in ultrasound is important because a reduced signal amplitude can affect the quality of the image produced. By knowing the attenuation that an ultrasound beam experiences traveling through a medium, one can adjust the input signal amplitude to compensate for any loss of energy at the desired imaging depth. [2]
Solid countermeasures to radiation damage consist of three approaches. Firstly, saturating the matrix with oversized solutes. This acts to trap the swelling that occurs as a result of the creep and dislocation motion. They also act to help prevent diffusion, which restricts the ability of the material to undergo radiation induced segregation. [26]
In condensed matter physics, scintillation (/ ˈ s ɪ n t ɪ l eɪ ʃ ən / SIN-til-ay-shun) is the physical process where a material, called a scintillator, emits ultraviolet or visible light under excitation from high energy photons (X-rays or gamma rays) or energetic particles (such as electrons, alpha particles, neutrons, or ions).
Radium-based luminescent paint is no longer used due to the radiation hazard posed to persons manufacturing the dials. These phosphors are not suitable for use in layers thicker than 25 mg/cm 2, as the self-absorption of the light then becomes a problem. Zinc sulfide undergoes degradation of its crystal lattice structure, leading to gradual ...
Radiation chemistry is a subdivision of nuclear chemistry which studies the chemical effects of ionizing radiation on matter. This is quite different from radiochemistry , as no radioactivity needs to be present in the material which is being chemically changed by the radiation.
Mass attenuation coefficients of selected elements for X-ray photons with energies up to 250 keV. The mass attenuation coefficient, or mass narrow beam attenuation coefficient of a material is the attenuation coefficient normalized by the density of the material; that is, the attenuation per unit mass (rather than per unit of distance).