emitting medium
21Light — For other uses, see Light (disambiguation). Visible light redirects here. For other uses, see Visible light (disambiguation) …
22Astronomy — (from the Greek words astron (ἄστρον), star , and nomos (νόμος), law ) is the scientific study of celestial objects (such as stars, planets, comets, and galaxies) and phenomena that originate outside the Earth s atmosphere (such as the cosmic… …
23Gamma ray burst emission mechanisms — are theories that explain how the energy from a gamma ray burst progenitor (regardless of the actual nature of the progenitor) is turned into radiation. These mechanisms are a major topic of research as of 2007. Neither the light curves nor the… …
24radiation measurement — ▪ technology Introduction technique for detecting the intensity and characteristics of ionizing radiation, such as alpha, beta, and gamma rays or neutrons, for the purpose of measurement. The term ionizing radiation refers to those… …
25electricity — /i lek tris i tee, ee lek /, n. 1. See electric charge. 2. See electric current. 3. the science dealing with electric charges and currents. 4. a state or feeling of excitement, anticipation, tension, etc. [1640 50; ELECTRIC + ITY] * * *… …
26information processing — Acquisition, recording, organization, retrieval, display, and dissemination of information. Today the term usually refers to computer based operations. Information processing consists of locating and capturing information, using software to… …
27Laser diode — Top: a packaged laser diode shown with a penny for scale. Bottom: the laser diode chip is removed from the above package and placed on the eye of a needle for scale …
28Galaxy groups and clusters — are the largest known gravitationally bound objects to have arisen thus far in the process of cosmic structure formation.[1] They form the densest part of the large scale structure of the universe. In models for the gravitational formation of… …
29Annus Mirabilis papers — Einstein, in 1905, when he wrote the Annus Mirabilis papers The Annus Mirabilis papers (from Latin annus mīrābilis, extraordinary year ) are the papers of Albert Einstein published in the Annalen der Physik scientific journal in 1905. These four… …
30LED lamp — An LED lamp (LED light bulb) is a solid state lamp that uses light emitting diodes (LEDs) as the source of light. The LEDs involved may be conventional semiconductor light emitting diodes, organic LEDs (OLED), or polymer light emitting diodes… …
