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	Wigner energy - Wikipedia, the free encyclopedia
		Wigner energy is created inside nuclear reactors that use graphite, a form of carbon, as neutron moderator.
		When the graphite is bombarded with neutrons from the reactor core, crystalline dislocations occur as a result of the Wigner effect, causing the graphite rods to swell and begin storing the energy.
		This energy is problematic for nuclear reactors because it can be spontaneously and rapidly released from the graphite in the form of heat, and unplanned excess heat is not a desirable situation within a nuclear reactor.
	en.wikipedia.org /wiki/Wigner_energy (278 words)

	Physics Today October 2002
		Wigner and Szilard, whose European-Hungarian background taught them what happens when a country is run by dictators such as Adolf Hitler, became obsessed in their desire to push forward the development of the atomic bomb.
		But Wigner had so much confidence in the accuracy of his calculations (backed, of course, by Fermi's experiments) that he insisted that, though the presence of water in the reactor would reduce the multiplication factor by perhaps 3%, enough reactivity would be left to make a reactor of modest size.
		Wigner's reactor was a cylindrical block of graphite with 1695 process tubes and Compton's mandated 200 tons of uranium.
	www.physicstoday.org /vol-55/iss-10/p42.html (3140 words)

	wiki/Wigner energy Definition / wiki/Wigner energy Research (Site not responding. Last check: 2007-11-05)
		Wigner energy is created inside nuclear reactors A nuclear reactor is a device in which nuclear chain reactions are initiated, controlled, and sustained at a steady rate (as opposed to a nuclear explosion, where the chain reaction occurs in a split second).
		As a result of the Wigner effect, the physical dimensions of the crystalline solid are changed and energy is stored in its structure; this is known as Wigner energy.
		This energy is problematic for nuclear reactors because it can be spontaneously and rapidly released from the graphite in the form of heat Heat (abbreviated Q, also called heat change) is the transfer of thermal energy between two bodies which are at different temperatures.
	www.elresearch.com /wiki/Wigner_energy (916 words)

	Wigner energy
		Energy stored in the irradiated graphite of a graphite reactor.
		The graphite atoms located at the interstitials cause this energy storage ( Wigner effect).
		At graphite temperatures of more than 250° C these voids recombine releasing energy, the Wigner energy.
	www.euronuclear.org /info/encyclopedia/w/wigner-energy.htm (48 words)

	wigner
		The problem is a type of energy called Wigner energy, which becomes trapped in the reactor's graphite moderator when neutrons dislodge carbon atoms from their crystalline lattice.
		Wigner energy was the main cause of the accident at Windscale in 1957.
		BNFL claims that there has not been a significant build-up of Wigner energy in the Magnox reactors because their high operating temperatures return the graphite crystal lattice to its original state through a process called annealing.
	www.mothersalert.org /wigner.html (679 words)

	ORNL Review Vol. 25, Nos. 3 and 4, 2002
		Wigner also acquired an assistant for the administration of research and development, Edgar Murphy, a scientist who had served as Army major in the Manhattan Engineer District office during the war.
		Wigner's best-known contribution was the curved design of the aluminum fuel plates in the reactor core.
		Wigner insisted the tests were completely safe, but Leber required that the debilitating regulations, which brought the tests to a virtual standstill, be meticulously observed.
	www.ornl.gov /info/ornlreview/rev25-34/chapter2.shtml (6993 words)

	Nat' Academies Press, Biographical Memoirs V.74 (1998)
		Technische Hochschule, Berlin While Wigner was strongly attracted to the field of physics, his father, who was of a very practical mind, insisted that instead he attend the Technische Hochschule in Berlin and focus on chemical engineering, so that he might be in a better position to earn a living in Hungary.
		Immediately after the discovery of the neutron in 1932, Wigner studied the early measurements of neutron-proton scattering, the properties of the deuteron, the connection between the saturation property of nuclear binding energies and the short range nature of the inter-nucleon force, and the symmetry properties of the force.
		Wigner's vital forces began to display attrition for the first time only when he was well into his eighties, the principal sign being partial, but significant memory loss.
	www.nap.edu /books/0309060869/html/364.html (5564 words)

	Eugene Paul Wigner, November 17, 1902 — January 1, 1995 \| By Frederick Seitz, Erich Vogt, and Alvin M. Weinberg \| ...
		While Wigner was strongly attracted to the field of physics, his father, who was of a very practical mind, insisted that instead he attend the Technische Hochschule in Berlin and focus on chemical engineering, so that he might be in a better position to earn a living in Hungary.
		When the results associated with it were joined with calculations of the exchange and correlation energies of a gas of free electrons carried out by Wigner, the so-called binding energy or energy of sublimation of the metal could be derived essentially from fundamentals using quantum mechanics.
		Although Wigner's non-tenured appointment at Princeton was extended beyond the initial five years, and he was promoted from visiting lecturer to visiting professor, it was not the tenured position he was looking for.
	bob.nap.edu /html/biomems/ewigner.html (6117 words)

	[No title]
		Although the electron correlation energy is just a few percent of the total energy of a chemical system, it is still about the same, sometimes even larger than the magnitude of energy changes in important physical and chemical processes.
		Recall that the Wigner form was resulted from the analytical parameterization of high- and low-density limits of the homogeneous electron gas for the intermediate density range, while Eq.
		Prediction of the conventional correlation energies for 21 diatomic and polyatomic molecules.
	www.unc.edu /~shubin/part4/thesis3.htm (2084 words)

	CERN Courier - Research highlights - IOP Publishing - article
		Wigner became Viki's mentor and the collaboration led to two papers published in 1930 (Weisskopf and Wigner, 1930a, 1930b).
		Instead, he worked out the theory of resonance fluorescence, that is, the absorption and re-emission of light by atoms, especially with the frequency of the incident beam near that of a difference frequency between two energy levels of the atom.
		The preliminaries had yielded three infinite quantities in field-free space - the total energy of the vacuum electrons, their charge and current densities, and the constant field-independent electric and magnetic polarizabilities of the vacuum.
	www.cerncourier.com /main/article/42/10/21 (2020 words)

	1 Nuclear Place - Nuclear Energy Books for Sale
		Eugene Wigner is one of the very few scientists that may safely be described as creators of 20th-century physics.
		Wigner himself gave a lively and critical account, which is published in this volume for the first time.
		It was a key factor in Germany's bid to harness atomic energy primarily as a source of electric power; its acute shortage was a factor in Japan's decision not to pursue seriously nuclear weaponry; its very existence was a nagging thorn in the side of the Allied powers.
	www.1nuclearplace.com /Nuclear-Energy-Books.htm (552 words)

	Implementation of the Cone Kernel for Speech Signal Analysis
		Since the TFR represents the amount of energy present in a signal as a function of time and frequency, it should be nonnegative everywhere.
		This smoothing is performed by convolving the Wigner distribution with a function referred to as the kernel of the TFR.
		After normalizing the burst amplitudes (Figures 5b, 5d, and 5e), we can see that most of the energy in the "t" and "k" bursts comes early in the burst, whereas the energy in the "p" burst is larger later in the burst than earlier.
	www.fink.com /papers/sphsc525.html (3140 words)

	Green's Functions
		Because the Wigner function measures the state of the device at a particular time, and its evolution is described by a first-order differential equation, it can only comprehend external interactions which occur instantaneously in time.
		Such behavior is termed ``Markovian.'' The energy dependence of the Green's functions permits a description of processes which are not local in time, or ``non-Markovian'' processes, because the energy argument provides a way to include convolution integrals over the past history of the system.
		In order for the energy of the phonon to be well-defined, the interaction must occur over a time greater than the oscillation period of the phonon.
	www.utdallas.edu /~frensley/technical/qtrans/node16.html (677 words)

	[No title]
		As a result of this calculation, Wigner stated (earlier) that "it would be unscientific to claim a useful life (for the reactor) of more than 100 days." Fortunately the lattice is able to readily recover its original form by a controlled temperature rise and annealing.
		Seitz and Wigner ended their brief article by saying "it is gratifying that a phenomenon which originated as a pure nuisance promises to provide us useful information about the solid state in general." But also radiation damage studies are done to be sure that the material in question can survive intensive radiation bombardment.
		Wigner was certainly well aware that there was a positive void coefficient in a water cooled reactor - boiling of water in a channel would increase the reactivity - and the report has a whole paragraph showing how the water reduced the reactivity constant from 1.10 to 1.07.
	phys4.harvard.edu /~wilson/publications/ppaper848.html (3181 words)

	Seitz (Site not responding. Last check: 2007-11-05)
		Soon after Wigner published his first work in the field, the mathematician Hermann Weyl, became interested in the topic and wrote a book on the subject, which was rather inaccessible for most physicists.
		Wigner, angry and now somewhat seasoned in vernacular terminology, terminated the negotiation abruptly by saying, "Go to Hell, please!" He often received requests from other individuals to read a research paper written by the latter.
		When the results associated with it were joined with calcula tions of the exchange and correlation energies of a gas of free electrons carried out by Wigner, the so-called binding energy or energy of sublimation of the metal could be derived essentially from fundamentals using quantum mechanics.
	www.physics.umd.edu /robot/wigner/seitz.html (6187 words)

	The Wigner-Seitz Method - Introduction
		Wigner and Seitz have developed a simple and fairly accurate method of calculating u( r) if the ion core potential is known.
		Bragg reflection leads to the existence of energy gaps in the distribution in energy of the states of conduction electrons.
		That is there are regions of energy in which solutions of the wave equation do not exist These gaps arise because the wave reflected from the neighbouring atom interferes constructively with the original wave of the home atom.
	www.chembio.uoguelph.ca /educmat/chm729/wscells/wigner.htm (684 words)

	Wigner (Site not responding. Last check: 2007-11-05)
		This energy is a problem for nuclear reactors because it can be spontaneous...
		Wigner's friend Wigner's friend is a quantum mechanics.
		In the Schrödinger's cat experiment while Wigner is out of the r...
	www.brainyencyclopedia.com /topics/wigner.html (79 words)

	U.S. Department of Energy Research News
		One is A. Baha Balantekin, who came to Oak Ridge as a Wigner Fellow in 1984-86 and now, somewhat ironically, holds the Wigner Chair at the University of Wisconsin, where the Nobel Laureate Eugene P. Wigner was once a professor.
		Because a large portion of American oil imports is used for transportation, the Department of Energy makes substantial investments at ORNL in several technologies designed both to improve fuel efficiency and reduce carbon emissions into the atmosphere.
		As U.S. researchers focus on domestic energy issues, they could easily miss the century's dominant energy challenge: to increase energy supplies for the world's growing population without contributing further to environmental degradation.
	www.eurekalert.org /doe/features.php?labs=282 (1084 words)

	AllRefer.com - Eugene Paul Wigner (Physics, Biography) - Encyclopedia (Site not responding. Last check: 2007-11-05)
		Eugene Paul Wigner [wig´n u r] Pronunciation Key, 1902–95, American physicist, b.
		After beginning his association with the Atomic Energy Commission in 1947, he served as a member of its general advisory committee from 1952 to 1957 and from 1959 to 1964.
		Wigner also received other major awards, including the National Science Medal and Atoms for Peace Award.
	reference.allrefer.com /encyclopedia/W/Wigner-E.html (223 words)

	Kent Against a Radioactive Environment
		The two component parts of British Energy, BEG Ltd in England and BEG (UK) Ltd in Scotland still operate as different licensees, and were preparing to integrate many functions such as management and technical support until late in 1998 when commercial obstacles to becoming one licensee emerged.
		In May, British Energy's profits and earnings fell by 19 and 15 per cent respectively, and the dividend was cut by 50%.
		Apprehension about Wigner energy is still evident, with NIREX refusing to allow graphite from the Windscale piles to be placed in its specially designed boxes on the basis that its behaviour is still ‘not clearly understood’.
	www.kare-uk.org /wana-june2000.htm (2985 words)

	Article in TCM-Manchester99: Technical assessment of the significance of Wigner energy for disposal of graphite wastes ... (Site not responding. Last check: 2007-11-05)
		Unless it can be shown that Wigner energy will not be released at a significant rate during operations such as waste packaging or handling of the package, or after disposal, future safety cases may be undermined.
		By appropriate selection of the range of activation energies and stored energies attributable to each population of defects, experimentally determined releases of stored energy as a function of temperature can be reproduced by the model.
		The Wigner energy release model has been used in combination with finite element thermal modelling to assess the temperature evolution of stacks of waste packages located within hypothetical disposal vaults.
	www.iaea.org /inis/aws/htgr/abstracts/abst_manchester_02.html (445 words)

	Article in TCM-Manchester99: The description of Wigner energy and its release from Windscale pile graphite for ... (Site not responding. Last check: 2007-11-05)
		These retain substantial amounts of Wigner energy and thus to support their packaging, storage and ultimate disposal, it is necessary to understand the release of the Wigner energy in slow, low temperature cycles, driven by the exothermic curing of the grout.
		The release of energy from each type of site can be described by a rate expression which is first order in the stored energy of the site, S, and has an associated activation energy, E, of decay.
		Simulation of stored energy release in anticipated storage conditions, where the graphite is subjected to a slow temperature cycle driven by the exothermic curing of the grout, shows that only a small portion of the total stored energy is released.
	www.iaea.org /inis/aws/htgr/abstracts/abst_manchester_03.html (398 words)

	Energy Dependent Breit-Wigner Width (Site not responding. Last check: 2007-11-05)
		The particular choice of the special function, where is the energy dependent Breit-Wigner width is discussed below.
		The total energy of a resonance produced at rest in colliding beams is m, and therefore the time dependence of its wave function is according to Eq.
		As is well known, the consequences of the imaginary pole in the propagator, or equivalently an imaginary part of the mass, is the exponential decay of the wave function.
	hep.bu.edu /~brown/phd/node109.html (568 words)

	Windscale Nuclear Incident
		During normal operation, neutrons striking the graphite result in distortion of the crystal structure of the graphite.
		Standard procedure after a normal reactor shutdown was to release the Wigner energy and restore the graphite to its original form.
		The releases of the Winger energy in the unmonitored areas got high enough to allow the graphite to catch fire.
	www.nucleartourist.com /events/windscal.htm (1058 words)

	Pebble bed reactor Article, Pebblebedreactor Information (Site not responding. Last check: 2007-11-05)
		PBRs are intentionally operated above the annealing temperature of graphite,so that Wigner energy is not accumulated.
		The Windscale reactor in England (not a PBR) hada fire from the release of energy stored as crystalline dislocations (Wigner energy) in the graphite.
		The lowdensity layer of graphite is surrounded by a higher-density nonporous layer of pyrolytic graphite.
	www.anoca.org /power/fuel/pebble_bed_reactor.html (3293 words)

	[No title]
		Wigner spent a brief time as research director of Clinton Laboratories (now Oak Ridge National Laboratory) beginning in 1946.
		Wigner was attending ceremonies in November 1963 to shut down ORNL's Graphite Reactor 20 years to the day after its historic criticality on November 4, 1943, when he learned that he had been awarded the Nobel prize.
		But unless such expressions as Wigner crystals, Wigner theorems, Wigner energy, and Wigner rules are struck from the scientific canon, he will not be forgotten by students of science.--Alice Rice ================================================================= CHANGES TO THE COMPUTER CODE COLLECTION Four changes were made to the computer code collection during the month.
	www-rsicc.ornl.gov /Newsletters/news.95/news95.jan (4189 words)

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