beam cross-section
91Diffraction topography — (short: topography ) is an X ray imaging technique based on Bragg diffraction. Diffraction topographic images ( topographs ) record the intensity profile of a beam of X rays (or, sometimes, neutrons) diffracted by a crystal. A topograph thus… …
92Attenuation coefficient — For attenuation coefficient as it applies to electromagnetic theory and telecommunications see propagation constant. For the mass attenuation coefficient , see the article mass attenuation coefficient. The attenuation coefficient is a quantity… …
93Airbus A380 — A380 redirects here. For other uses, see A380 (disambiguation). A380 A Singapore Airlines …
94Permanent way — The permanent way means the physical elements of the railway line itself: generally the pairs of rails typically laid on sleepers embedded in ballast, intended to carry the ordinary trains of a railway. This page describes British practice and… …
95Two-photon absorption — (TPA) is the simultaneous absorption of two photons of identical or different frequencies in order to excite a molecule from one state (usually the ground state) to a higher energy electronic state. The energy difference between the involved… …
96nuclear fusion — fusion (def. 4). [1895 1900] * * * Process by which nuclear reactions between light elements form heavier ones, releasing huge amounts of energy. In 1939 Hans Bethe suggested that the energy output of the sun and other stars is a result of fusion …
97Optical fiber — A bundle of optical fibers A TOSLINK fiber optic audio c …
98Low-energy ion scattering — LEIS redirects here; for the Hawaiian garland see Lei (Hawaii). Low energy ion scattering spectroscopy (LEIS), sometimes referred to simply as ion scattering spectroscopy (ISS), is a surface sensitive analytical technique used to characterize the …
99electromagnetic radiation — Physics. radiation consisting of electromagnetic waves, including radio waves, infrared, visible light, ultraviolet, x rays, and gamma rays. [1950 55] * * * Energy propagated through free space or through a material medium in the form of… …
100Rayleigh scattering — This article is about the optical phenomenon. For the magnetic phenomenon, see Rayleigh law. For the stochastic distribution, see Rayleigh distribution. For the wireless multipath propagation model, see Rayleigh fading. Rayleigh scattering causes …
