Creation
Charged particles such as electrons, positrons, and protons may be separated from their common surrounding. This can be accomplished by e.g. thermionic emission or arc discharge. The following devices are commonly used as sources for particle beams:
- ion source
- cathode ray tube, or more specifically in one of its parts called electron gun. This is also part of traditional television and computer screens.
- photocathodes may also be built in as a part of an electron gun, using the photoelectric effect to separate particles from their substrate.
- Neutron beams may be created by energetic proton beams which impact on a target, e.g. of beryllium material. (see article Particle therapy).
Read more about this topic: Particle Beam
Famous quotes containing the word creation:
“Some collaboration has to take place in the mind between the woman and the man before the art of creation can be accomplished. Some marriage of opposites has to be consummated. The whole of the mind must lie wide open if we are to get the sense that the writer is communicating his experience with perfect fullness.”
—Virginia Woolf (1882–1941)
“We hold these truths to be sacred and undeniable; that all men are created equal and independent, that from that equal creation they derive rights inherent and inalienable, among which are the preservation of life, and liberty, and the pursuit of happiness.”
—Thomas Jefferson (1743–1826)
“Man is a masterpiece of creation if for no other reason than that, all the weight of evidence for determinism notwithstanding, he believes he has free will.”
—G.C. (Georg Christoph)