Spontaneousemission is the process by which a light source such as an atom , molecule , nanocrystal ..., e.g., the ground state and emits a photon . Spontaneousemission of light or luminescence is a fundamental ... math hbar math is the reduced Planck constant . The phase waves phase of the photon in spontaneousemission is random as is the direction the photon propagates in. This is not true for stimulated emission . An energy level diagram illustrating the process of spontaneousemission is shown below Image ... math is the rate of spontaneousemission. In the rate equation math A 21 math is a proportionality ... photon in it. Spontaneousemission in free space depends upon vacuum fluctuations to get started. ref name Yokoyama, cite book author Hiroyuki Yokoyama & Ujihara K title Spontaneousemission and laser ... the atom must decay by spontaneousemission. The time the light source remains in the excited state ... their energy in the absence of any external source of photons. This is not spontaneousemission ... molecules present inside the bulk. Rate of spontaneousemission The rate of spontaneousemission i.e., the radiative rate can be described by Fermi s golden rule . ref B. Henderson and G. Imbusch .... In a homogeneous medium, such as free space , the rate of spontaneousemission in the dipole ... has been used to check the math omega 3 math frequency dependence of the spontaneousemission .... L. Vos and D. Vanmaekelbergh, Frequency dependent spontaneousemission rate from CdSe and CdTe nanocrystals ... panels, lasers for startup normal continuous operation works by stimulated emission instead and light ... Spontaneous transitions was not explainable within the framework of the old quantum theory, that is a theory ... of spontaneous transitions from one stationary state to another, one finds that it is zero. In order to explain spontaneous transitions, quantum mechanics must be extended to a second quantized ... 0849337860 url http books.google.com books?id J 0ZAwf6AQ0C&printsec frontcover&dq 22spontaneous emission ... more details
Amplified spontaneousemission ASE or superluminescence is light , produced by spontaneousemission , that has been optical amplifier optically amplified by the process of stimulated emission in a gain medium . It is inherent in the field of random laser s. Origins and problems ASE is produced when a laser gain medium is laser pumping pumped to produce a population inversion . Feedback of the ASE by the laser s optical cavity may produce laser operation if the lasing threshold is reached. Excess ASE is an unwanted effect in lasers, since it limits the maximum gain that can be achieved in the gain medium. ASE creates serious problems in any laser with high gain and or large size. In this case, a mechanism to absorb or extract the incoherent ASE must be provided, otherwise the excited state excitation of the gain medium will be depleted by the incoherent ASE rather than by the desired Coherence physics coherent laser radiation . ASE is especially problematic in lasers with short and wide optical cavities, such as disk laser s active mirrors . ref name uns cite journal author D.Kouznetsov coauthors J.F.Bisson, K.Takaichi, K.Ueda title Single mode solid state laser with short wide unstable cavity url http josab.osa.org abstract.cfm?id 84730 journal JOSAB volume 22 issue 8 pages 1605 1619 year 2005 doi 10.1364 JOSAB.22.001605 bibcode 2005JOSAB..22.1605K ref . ASE in organic dye lasers ASE in pulsed organic dye laser s can have very broad spectral characteristics as much as 40 50 nm wide and presents, as such, a serious challenge in the design and operation of tunable narrow linewidth dye lasers. In order to suppress ASE, in favor of pure laser emission, researchers use various approaches including optimized laser cavity designs. ref cite book editors F. J. Duarte L. W. Hillman ... amplified spontaneousemission as a probe to study self healing properties. ref Natnael B. Embaye ... ref References reflist See also maser disk laser DEFAULTSORT Amplified SpontaneousEmission Category ... more details
wiktionarypar emissionEmission may refer to Flue gas , also Exhaust gas , flue gas occurring as a result of the combustion of a fuel Emission of Air pollution air pollutant s Greenhouse gas Greenhouse gas emissions Emission of greenhouse gases Emission electromagnetic radiation , the process by which the energy of a photon is released by another entity Emission radiocommunications , the radio signal usually modulated emitted from a radio transmitter Emission coefficient , a coefficient in the power output per unit time of an electromagnetic source Emission factor Emission line , or spectral line , a dark or bright line in an otherwise uniform and continuous spectrum Emission nebula , a cloud of ionized gas emitting light of various colors Emission spectroscopy , mass spectroscopy, photoemission spectroscopy, flame emission spectroscopy and other types of spectroscopy Emission standard Emission theory , a competing theory for the special theory of relativity, explaining the results of the Michelson Morley experiment Emission theory vision , the proposal that visual perception is accomplished by rays of light emitted by the eyes Emissions trading Ejaculation , the ejecting of semen from the penis also, specifically Nocturnal emission , ejaculation experienced during sleep Light emission Thermionic emission , the flow of charged particles called thermions from a charged metal or a charged metal oxide surface, archaically known as the Edison effect Noise emission see Noise Exhalation , especially where the velocity of exhaled air can influence the harmonic generating properties of a vibrating body, such as the reed of a musical instrument like the saxophone. Disambig als Emission bg cs Emise da Emission de Emission fr mission lv Emisija nl Emissie no Emisjon nn Emisjon pl Emisja pt Emiss o rm Emissiun ru simple Emission sr sv Emission ... more details
G. Scharff Goldhaber and G. S. Klaiber year 1946 month title SpontaneousEmission of Neutrons ...Spontaneous fission SF is a form of radioactive decay characteristic of very heavy isotope s. It is theoretically possible for any atomic nucleus whose mass is greater than or equal to 100 atomic mass unit s u , i.e. elements near ruthenium. In practice, however, spontaneous fission is only energetically feasible for atomic mass es above 230 u elements near thorium . The elements most susceptible to spontaneous ... , and the trans actinide elements, such as rutherfordium . For uranium and thorium, the spontaneous ... the activity of a sample containing these elements. Mathematically, the criterion for whether spontaneous ..., 235 for U 235 . As the name suggests, spontaneous fission gives the same result as induced nuclear ... the atom having been struck by a neutron or other particle as in induced nuclear fission. Spontaneous fissions release neutrons as all fissions do, so if a critical mass is present, a spontaneous fission can initiate a chain reaction. Also, radioisotopes for which spontaneous fission is a nonnegligible ..., this is a Poisson process for very short time intervals the probability of a spontaneous fission is proportional to the length of time. The spontaneous fission of uranium 238 leaves trails of damage ... dating . Spontaneous fission rates Spontaneous fission rates ref cite book last Shultis first J ... production. SimpleNuclide Plutonium 240 s high rate of spontaneous fission events makes it an undesirable ... of Nuclear weapon design Implosion type weapon implosion method . Spontaneous fission can occur ... neutrons, it was difficult to distinguish between induced and spontaneous fission events. Cosmic rays can be reliably shielded by a thick layer of rock or water. The spontaneous fission was identified ... 60 m deep underground. ref http n t.ru ri ps pb092.htm K. Petrzhak How the spontaneous fission ... livechart The LIVEChart of Nuclides IAEA with filter on spontaneous fission decay, in http ... more details
Image Album2b.jpg thumbnail right 220px Cover art for Spontaneous Illumination Spontaneous Illumination was Entheogenic band Entheogenic s second and most successful album. It was released in November of 2003 for the Germany German label C.O.R.N. Recordings and went to Number 1 on the German Chill Out Charts, where it remained at number 1 for 8 weeks. Spontaneous Illumination stayed in the Top 10 for an additional 12 weeks. Track listing Ground Luminosity 11 42 Habitual Overtones 8 54 Pagan Dream Machine 9 45 Mindless 9 41 Invisible Landscapes 9 35 Twilight Eyes 12 32 Spaced 9 47 External links http www.cornrecordings.com c.o.r.n. recordings label homepage http www.cdbaby.com entheogenic Spontaneous Illumination at CDBaby.com includes reviews, description, samples and the option to purchase this album http www.psyshop.com shop CDs cor cor1cd001.html Spontaneous Illumination at PsyShop.com Includes a description, samples and the option to purchase this album Category Ambient albums hu Spontaneous Illumination ... more details
Multiple issues orphan September 2010 notability June 2009 unreferenced June 2009 Spontaneous composition is music performed, occurring, or resulting from a sudden natural impulse, tendency, or inclination without effort or premeditation natural and unconstrained unplanned. ref name test http www.spontaneouscomposition.com Link text , additional text. ref Musical improvisation Improvisation is one possible compositional tool used in creating a spontaneous composition . References references Category Musical improvisation Music theory stub ... more details
A spontaneous process is the time evolution of a system in which it releases Gibbs free energy free energy usually as heat and moves to a lower, more thermodynamically stable energy state. ref http www.chem.purdue.edu gchelp gloss sponprocess.html Spontaneous process Purdue University ref ref http cancerweb.ncl.ac.uk cgi bin omd?spontaneous process Spontaneous process University of Newcastle upon Tyne ... in free energy, but a positive change for the surroundings. A spontaneous process is capable of proceeding ... of thermodynamics govern the direction of a spontaneous process, ensuring that if a sufficiently ... and H is negative, a process is spontaneous p When S is positive and H is positive, a process is spontaneous at high temperatures, where exothermic ity plays a small role in the balance. p When S is negative and H is negative, a process is spontaneous at low temperatures, where exothermicity is important. p When S is negative and H is positive, a process is not spontaneous at any temperature, but the reverse process is spontaneous. blockquote The second law of thermodynamics states that for any spontaneous process the S of the system must be greater than or equal to zero, yet a spontaneous chemical reaction can result in a negative change in entropy. This does not contradict ... is still positive. Another way to view the fact that some spontaneous chemical reactions can lead .... For example, the decay of diamonds into graphite is a spontaneous process occurs very slowly, taking ... on the chemical kinetics of the reaction. Every reactant in a spontaneous process has a tendency ... at a time. e.g. Water converting to ice is a spontaneous process because ice is more stable since it is of lower energy. However, the formation of water is also a spontaneous process as water is the more random state. See also Endergonic reaction reactions which are not spontaneous at standard temperature, pressure, and concentrations. Diffusion spontaneous phenomena that minimize Gibbs free ... more details
Spontaneous healing , also called spontaneous remission or spontaneous regression , means an unexpected ... used for unexpected transient or final improvements in cancer . Spontaneous remissions concern cancers of the haematopoietic system blood cancer, e.g. leukemia , while spontaneous regressions concern palpable tumors however, both notions are often used interchangeably. Definition The spontaneous ..., Everson TC Spontaneous Regression of Cancer . WB Saunders, Philadelphia, PA. 1966 Buch ref The partial .... Frequency It has long been assumed that spontaneous regressions, let alone cures, from cancer are rare ... be largely under or overestimated. For one, not all cases of spontaneous regression can be apprehended ... of spontaneous regression most likely was drastically underrated. In a carefully designed study on mammography it was found that 22 of all breast cancer cases underwent spontaneous regression. ref Per ... Mammography, Arch. Intern Med., Vol 168 NO. 21 , Nov 24, 2008 ref Searching for cancer AND spontaneous .... Cause Everson and Cole offered as explanation for spontaneous regression from cancer In many of the collected cases ... it must be acknowledged that the factors or mechanisms responsible for spontaneous ... Everson T., Cole W. 1968 Spontaneous Regression of Cancer Philadelphia, JB Saunder & Co Book ref ... little conclusive data that explains the occurrence of spontaneous regression. . ref name Challis Challis GB, Stam HJ. 1990 The spontaneous regression of cancer. A review of cases from 1900 1987 Acta ... growth of new blood vessels is discussed as cause of spontaneous regression. But both mechanisms ..., Garland Science 2007 ref A great number, if not a majority of spontaneous regressions from cancer ... , Critical Reviews Immunology 2008 Vol 28, 95 107 ref Reviews Rohdenburg 1918 summarizes 185 spontaneous ... reference to spontaneous recession . J Cancer Res 1918 3 193 225 ref Fauvet reports 202 cases between 1960 1964, ref Fauvet J Spontaneous cancer cures and regressions. Rev Prat. 1964 Jun 11 14 2177 ... more details
material which can undergo a kind of spontaneous and potentially very violent explosion when exposed ... fermentation . ref cite web url http www.wa hay.org publications Spontaneous 20Combustion 20in 20Hay 20Stacks.pdf title Spontaneous Combustion in Hay Stacks accessdate 2008 05 09 work ref ref cite web url http www1.agric.gov.ab.ca department deptdocs.nsf all agdex10721 title Spontaneous combustion .... ref cite press release url http www.saftek.net worksafe bull94.txt title EH 93 4 The Fire Below Spontaneous ... 16 ref Pyrite oxidation is often the cause of coal spontaneous ignition in old Mine tailings . Pistachio nuts are highly flammable when stored in large quantities, and are prone to self heating and spontaneous .... People have also been reported as spontaneous human combustion spontaneously combusting . This phenomenon is not considered true spontaneous combustion, as it is largely attributed to the wick ... In internal combustion engine s, spontaneous ignition is called either compression ignition or preignition ... to detonation as in spark ignition engines. In humans Main Spontaneous human combustion The spontanoeus ... means. References Reflist External links http www.saftek.net worksafe bull94.txt Article on the spontaneous ... rbjul05 index.html Spontaneous combustion demonstration Category Combustion da Selvant ndelse de Selbstentz ndung ... more details
Orphan date September 2010 Spontaneous conception may refer to the birth of a second child after the birth of a child conceived through in vitro fertilisation . There is a overall 18 chance of spontaneous conception after an In Vitro Fertilization treatment, but that chance rose to 37 among younger women less than 27 years . But the likelihood also depends of the sperm performance of the man and the egg count of the woman. ref http newsimg.bbc.co.uk 1 hi health 253374.stm ref In Psychology It also can refer to conceptions about the world that we form without any formal education. Often these are connected with physics . They may be wrong concepts, like heavier objects fall faster or bigger objects are heavier . Piaget thinks they are made by introspection. Vygotsky believes they may help the learning of scientific concepts more than having no conception about one event. ref Alberto Gaspar. O ENSINO INFORMAL DE CI NCIAS DE SUA VIABILIDADE E INTERA O COM O ENSINO FORMAL CONCEP O DE UM CENTRO DE CI NCIAS. Depto. de F sica e Qu mica UNESP. Guaratinguet SP. Dispon vel em http www.journal.ufsc.br index.php fisica article viewFile 7493 6872 acesso em 25 09 2010 ref References reflist DEFAULTSORT Spontaneous Conception Category Medicine Category Gynecology Category Childbirth pt Concep o espont nea ... more details
see also Emergence Self organization Spontaneous order is the spontaneous emergence of order out of seeming ... evolved through spontaneous order. ref name rclt1982 http www.econlib.org library Essays LtrLbrty bryTSO.html The Tradition of Spontaneous Order , N. Barry, Institute for Humane Studies Literature of Liberty ... ecosystem s and to the universe itself as ultimate examples of this phenomenon. Spontaneous order is also used as a synonym for any Emergence emergent behavior of which self interested spontaneous ... 369 c. 286 B.c. was the first to work out the idea of spontaneous order, before Pierre Joseph Proudhon ... Principle. ref Proudhon s position was that freedom is prerequisite for spontaneous order to take place, rather than liberty being the result of spontaneous order. Hence his statement, liberty is not the daughter ... develop and inquire into the idea of the market as a spontaneous order the result of human action ... requisite for spontaneous order to take place. Citation needed date June 2008 Examples Markets ... are creative of a spontaneous order a more efficient allocation of societal resources than any design ... of Spontaneous Order and the Scottish Enlightenment. Routledge. 2001. p. 2 ref They claim this spontaneous ... , describes spontaneous order as follows blockquote Spontaneous order is what happens when you ... bureaucracy. ref John Stossel Stossel, John 2011 02 10 http reason.com archives 2011 02 10 spontaneous order singlepage Spontaneous Order , Reason magazine Reason ref blockquote However, some Who date ... studies The concept of spontaneous order is closely related with modern game studies . As early as in the 1940s ... elite, and that true spontaneous order would arise if it was eliminated. Construed by some but not all as the ushering in of organization by anarchist law . In the anarchist view, such spontaneous ... with the anarchist vision, since it harbours a view of society as spontaneous order. ref cite ... of spontaneous order can also be seen in the works of the Russian slavophile movements and in specific ... more details
Spontaneous magnetization is the term used to describe the appearance of an ordered Spin physics spin state magnetization at zero applied magnetic field in a ferromagnetic or ferrimagnetic material below a critical point physics critical point called the Curie temperature or math var T sub C sub var . At temperatures above math var T sub C sub var , the material is paramagnetic and its magnetic behavior is dominated by spin wave s or magnon s, which are boson collective excitations with energies in the meV range. The magnetization that occurs below math var T sub C sub var is a famous example of the spontaneous symmetry breaking spontaneous breaking of a global symmetry, a phenomenon that is described by Goldstone s theorem . The term symmetry breaking refers to the choice of a magnetization direction by the spins, which have spherical symmetry above math var T sub C sub var , but a preferred axis the magnetization direction below math var T sub C sub var . To first order, the temperature dependence of spontaneous magnetization at low temperatures is given by Felix Bloch Bloch s Law ref harvnb Ashcroft Mermin 1976 p 708 ref math M T M 0 left 1 T T c right 3 2 , math where math M 0 is the spontaneous magnetization at absolute zero. The decrease in spontaneous magnetization at higher temperatures is caused by the increasing excitation of spin waves. In a particle description, the spin waves correspond to magnons, which are the massless Goldstone boson s corresponding to the continuous symmetry broken symmetry . Near the Curie temperature, math M T propto left T T c right beta, math where math var &beta var is a critical exponent that depends on composition. The exponent is math 0.34 for iron and math 0.51 for nickel . ref harvnb Chikazumi 1997 pp 128 129 ref See also Magnetization Ferromagnetism Ferrimagnetism Notes references References cite book last Chikazumi first S shin title Physics of Ferromagnetism publisher Clarendon Press year 1997 isbn 0 19 851776 9 ref harvnb ... more details
in the S1 condition where there was a rest period of eight days. Spontaneous recovery may help ... DEFAULTSORT Spontaneous Recovery Category Behavioral concepts psych stub ... more details
Spontaneous Broadway is an advanced long form improvisational theatre improvised performance, usually based on audience suggestions. The audience typically submits titles of songs that have never been written, and the performers choose suggestions to create songs, the audience votes through acclamation on their favourite song, which is then used as the core of a brand new Broadway theatre Broadway musical. The format received a favorable review from The New York Times when it premiered in New York in 1995. ref cite news url http theater2.nytimes.com mem theater treview.html? r 1&res 990CE4D7113BF93BA35750C0A963958260&oref slogin Dead link date September 2010 bot RjwilmsiBot ref Though not required or necessarily encouraged by improv professionals, elements of humor inevitably surface in the performance because of the surprising and playful nature of improvisation and its use of typical Broadway stereotypes. The performers songs are supported by an onstage musician or band that improvises the music, generally in the style of typical show tunes. The format was created in New York City and has been performed by a number of different companies around the US. The Spontaneous Broadway format was created by Kat Koppett in association with Freestyle Repertory Theatre in New York. Koppett is a 20 year improv veteran, having worked with Freestyle Repertory Theatre and San Francisco s BATS Improv . She is currently a performer with and Training director for the Mop & Bucket Company, an improv troupe based in the Capital District of New York State. ref http www.mopco.org ref In 1995, TheaterWeek Magazine named Kat one of the year s Unsung Heroes for her creation of Spontaneous Broadway, which is now performed regularly by teams of actors all over the world. On 6 April 2010, the show began its run at the Melbourne Comedy Festival in Australia. It went down very well with the audience in the Arts Centre s Fairfax Studio. Sources Cite book last Koppett first Kat title Training to Imagine ... more details
Abiogenesis Spontaneous generation or Equivocal generation is an obsolete principle Fact date March ... and cell theory . The disproof of ongoing spontaneous generation is no longer controversial, now ... Spontaneous generation refers to both the supposed process by which life would systematically ... Spontaneous Generation chapterurl http xtf.lib.virginia.edu xtf view?docId DicHist uvaBook tei DicHist1.xml ... mature like other animals, or they would not have survived. Anaximander also claimed that spontaneous ... the fluid stage of the earth and the formation of land. He too held to a spontaneous generation ... the spontaneous generation of life, but held that there had to be trials of combinations of parts ..., whilst others grow spontaneously and not from kindred stock and of these instances of spontaneous ... faqs abioprob spontaneous generation.html title Spontaneous Generation and the Origin of Life ... are characterized by forming by spontaneous generation in mud, but differ based upon the material ... also dissented towards spontaneous generation, claiming that a variety of anchovy did not generate ... Branta leucopsis Augustine of Hippo discussed spontaneous generation in City of God book The City of God ... url http books.google.com ?id Fo7tQ5mG21IC&printsec frontcover PPA17,M1 chapter Chapter 2 Spontaneous ... science declined, although spontaneous generation generally went unchallenged. New descriptions ... 2009 01 23 isbn 1158377770 ref Spontaneous generation is discussed as a fact in literature well ... unanswered and the additional idea that eels reproduced from corruption of age was mentioned, the spontaneous ... to disprove spontaneous generation The ancient beliefs were subjected to testing. In 1668, Francesco ... experiment to challenge spontaneous generation, he placed meat in a variety of sealed, open, and partially covered containers. ref name slowdeath Cite web url http www.accessexcellence.org RC AB BC Spontaneous Generation.php title The Slow Death of Spontaneous Generation 1668 1859 accessdate 2008 12 ... more details
The text of this new article was adapted from a clarification given by User alteripse on Talk Seale Harris Spontaneous hypoglycemia as of 17 29, 7 February 2010 UTC The term spontaneous hypoglycemia was coined by the physician Seale Harris . ref name alstatearchive cite web title Seale Harris work Alabama State Archives url http www.archives.state.al.us famous s harris.html accessdate 2010 02 11 Who stated their source to be Alabama Hall of Fame , 1968 ref It is a vague term that, today 2010 , is not considered very useful by doctors interested in hypoglycemia . Though it still has historical value. In some contexts it refers to hypoglycemia that is not induced by exogenous insulin i.e., diabetic hypoglycemia . In other contexts it is equivalent to idiopathic hypoglycemia i.e., Idiopathic of unknown cause . And some people use it to encompass idiopathic hypoglycemia with measured low blood glucose, reactive hypoglycemia with measured low glucose, And it may refer to idiopathic postprandial syndrome . Bottom line The term is considered to be too imprecise to be very useful. History When Seale Harris was writing about hypoglycemia, the only two kinds that were well understood were diabetic hypoglycemia and hypoglycemia resulting from insulinoma . He asserted that were likely other types as well. His assertion was widely enough accepted that the diagnosis was assigned to, or claimed by, a large number of patients with otherwise unexplained adrenergic symptoms. His contemporary, a surgeon named Allen Whipple Allen Oldfather Whipple , formulated the Whipple criteria as a sieve to sort out those who might have an insulinoma requiring surgery from those with symptoms but not measured low blood glucose. They are still in use for exactly that purpose. See also Whipple s triad also called Whipple s criteria. Hypoglycemia Diabetic hypoglycemia Reactive hypoglycemia Idiopathic hypoglycemia Idiopathic postprandial syndrome Ketotic hypoglycemia References references Category Endo ... more details
Spontaneous potential SP , also called self potential , is a naturally occurring Electric potential electric potential difference in the Earth, measured by an electrode relative to a fixed reference electrode. Although SP differences have been measured along the Earth s surface in mineral exploration, today it is used almost exclusively by the oil and gas industry for formation evaluation in boreholes. SP was first recognized by Conrad Schlumberger , Marcel Schlumberger, and E.G. Leonardon in 1931, and the first published examples were from Russian oil fields. Physics Spontaneous potentials SP are usually caused by charge separation in clay or other minerals, due to presence of semi permeable interface impeding the diffusion of ions through the pore space of rocks, or by natural flow of a conducting fluid through the rocks. The origin of SP across formation can be attributed to two processes involving the movement of ions Streaming potential E sub k sub Electrochemical potential E sub c sub Streaming potential originates from the flow of an electrolyte water over naturally charged solids i.e., surfaces that acquired electrokinetic potential electrokinetic or zeta potential . The streaming potential appears when mud filtrate is forced into the formation under the differential pressure between mud column and formation. The streaming potential is produced when the flow takes place ... by that across the shale. As such, in most cases, the spontaneous potential measured is only related ... sub 10 sub a sub w sub a sub mf sub Since spontaneous potential is a measure of electrochemical potential ... resistivity respectively. The ideal spontaneous potential across clean bed is known as Static SP SSP ... technique Spontaneous potential can be measure by placing one probe of a voltmeter at the Earth ... Spontaneous potential logging External links http www.slb.com content services resources books log charts spontaneous potential.asp Schlumberger Correction Charts for SP References reflist M.Gondouin ... more details
of the incident wave. This is in contrast to spontaneousemission which occurs without regard ... . Lacking a feedback mechanism, laser amplifier s and Amplified spontaneousemission superluminescent sources also function on the basis of stimulated emission. Stimulated emission is a quantum mechanics ... spontaneousemission . The phase associated with the photon that is emitted is random ... of transitions between two states is enhanced beyond that due to spontaneousemission. Such a transition ... by the process of spontaneousemission , releasing the difference in energies between the two states ... light sources which depend on spontaneousemission is that the emitted photons have the same frequency ... of stimulated or spontaneousemission will be decreased according to the so called line shape ... Rabi cycle Spontaneousemission DEFAULTSORT Stimulated Emission Category Electromagnetic radiation ...In optics , stimulated emission is the process by which an atomic electron or an excited molecular state ... equilibrium, absorption exceeds stimulated emission because there are more electrons in the lower ... the rate of stimulated emission exceeds that of absorption, and a net optical amplification can be achieved ... are only allowed in between discrete energy levels such as the two shown above. This leads to emission ... and thermal emission . An external electromagnetic field at a frequency associated with a transition ... photon this is the process of stimulated emission . Mathematical Model Stimulated emission can be modelled ... energy state. This process is known as stimulated emission . In a group of such atoms, if the number of atoms in the excited state is given by N sub 2 sub , the rate at which stimulated emission occurs ... field at frequency . The rate of emission is thus proportional to the number of atoms in the excited ... for this transition must be identical to that for stimulated emission math B 12 B 21 math . Thus absorption and stimulated emission are reverse processes proceeding at somewhat different rates ... more details
diagram of spontaneousemissionEmission spectroscopy is a spectroscopy spectroscopic technique which ... particles and their Thomson differential cross section area solid angle . SpontaneousEmission A warm ...The emission spectrum of a chemical element or chemical compound is the spectrum of frequencies of electromagnetic radiation Emission electromagnetic radiation emitted by the element s atom s or the compound s molecules when they are returned to a lower energy state. Each element s emission spectrum .... Similarly, the emission spectra of molecules can be used in chemical analysis of substances. Emission light In physics , emission is the process by which a higher energy quantum mechanical state of a particle becomes converted to a lower one through the emission of a photon , resulting in the production ... substances, the amount of emission varies with the temperature and the spectroscopy spectroscopic composition of the object, leading to the appearance of color temperature and emission lines . Precise measurements at many wavelengths allow the identification of a substance via emission spectroscopy . Emission of radiation is typically described using semi classical quantum mechanics the particle ... photons form the element s emission spectrum. The fact that only certain colors appear in an element s atomic emission spectrum means that only certain frequencies of light are emitted. Each of these frequencies ... photon s having certain energies are emitted by the atom. The principle of the atomic emission spectrum ... ground level the light is emitted. Image Emission spectrum H.png none frame Emission spectrum of Hydrogen Image Emission spectrum Fe.png none frame Emission spectrum of Iron Radiation from molecules ... may appear as a spectral continuum. Molecular emission is the mechanism behind the sulfur lamp and the deuterium arc lamp . Emission spectroscopy Light consists of electromagnetic radiation of different ... a certain amount of energy. The emission spectrum can be used to determine the composition of a material ... more details
class wikitable align right Neutron emitters to left of lower dashed line Isotones 2 0 Isotones 1 0 Isotones 0 0 Isotones 1 0 Isotones 2 0 Isotones 3 0 Isotones 4 0 Isotones 5 0 Isotones 6 0 Isotones 7 0 Isotones 8 0 Isotones 9 0 Isotones 10 0 Isotones 11 0 Isotones 12 0 Isotones 13 0 Isotones 14 0 Neutron emission is a type of radioactive decay of atoms containing excess neutron s, in which a neutron is simply ejected from the nucleus. Two examples of isotopes which emit neutrons are helium 5 and beryllium 13 . However, the decay of helium 5 is also by definition a case of alpha decay. Many heavy isotopes, most notably californium 252 , emit neutrons among the products of a different radioactive decay process, spontaneous fission . Neutrons are absorbed and emitted in the process of nuclear fission , a nuclear chain reaction propagated by neutrons. Delayed neutron s emitted by neutron rich fission product s aid control of nuclear reactor s by making reactivity change much slower than it would be for prompt neutron s alone. See also Neutron radiation External links Image Ndslivechart.png http www nds.iaea.org livechart The LIVEChart of Nuclides IAEA with filter on delayed neutron emission decay, in http www nds.iaea.org livechart Java or http www nds.iaea.org relnsd vcharthtml VChartHTML.html HTML Image Queryensdf.jpg 45 px http www nds.iaea.org queryensdf Nuclear Structure and Decay Data IAEA with query on Neutron Separation Energy nuclear stub Nuclear processes Category Nuclear physics Category Radioactivity Category Neutron Emission ca Emissi de neutrons de Neutronenemission fr mission de neutron ja ko pl Emisja neutronu sv Neutronemission tr N tron emisyonu zh ... more details
. During puberty , 13 of males experience their first ejaculation as a result of a nocturnal emission ... their first ejaculation through a nocturnal emission were older than those experiencing ... resulting from a nocturnal emission was delayed a year or more from what would have been developmentally ... teach that under the law of Moses a man who had a nocturnal emission incurred ritual defilement. bquote If a man has an emission of semen, he shall bathe his whole body in water and be unclean Hebrew ... emission literally by reason of what happens to him by night , then he shall go outside the camp ... relates more specifically to priests, requiring a man who has had an emission of semen, among other ... masturbation or intercourse , nocturnal emission is not such a cause. He or she is still required to bathe ... wet dream Reflist SleepSeries2 DEFAULTSORT Nocturnal Emission Category Orgasm Category Sleep ... Polu o noturna ru simple Nocturnal emission sk Pol cia v ron semena fi Y llinen siemensy ksy ... more details
Unreferenced date December 2009 A spurious emission is any radio frequency not deliberately created or transmitted, especially in a device which normally does create other frequencies. A harmonic or other signal outside a transmitter s assigned channel would be considered a spurious emission. From ITU, 1.145 Spurious emissionEmission on a frequency or frequencies which are outside the necessary bandwidth and the level of which may be reduced without affecting the corresponding transmission of information. Spurious emissions include harmonic emissions, parasitic emissions, intermodulation products and frequency conversion products but exclude out of band emissions. DEFAULTSORT Spurious Emission Category Radio technology ja ... more details
In atomic physics , exoelectron emission EE is a weak electron emission, appearing only from pretreated irradiated, deformed etc objects. ref name Oster1999 citation last Oster first L. year 1999 title Classification of Exoelectron Emission Mechanisms journal Phys. Status Solidi A volume 174 issue 2 pages 431 doi 10.1002 SICI 1521 396X 199908 174 2 431 AID PSSA431 3.0.CO 2 Z last2 Yaskolko first2 V. last3 Haddad first3 J. ref ref name Gerasimov1976 citation last Gerasimov first A. B. year 1976 title On the physical mechanism of exoelectron emission journal Phys. Status Solidi A volume 35 issue 2 pages K131 doi 10.1002 pssa.2210350256 last2 Dolidze first2 G. M. last3 Mizandari first3 L. A. last4 Tsertsvadze first4 A. A. ref The pretreatment excitation turns the objects into an unequilibrial state. EE accompanies the relaxation of these unequilibria. The relaxation can be stimulated e.g. by slight heating or longwave illumination, not causing emission from untreated samples. Accordingly, thermo and photostimulated EE TSEE, PSEE are distinguished. Thus, EE is an electron emission analogue of such optical phenomena as phosphorescence , thermo and photostimulated luminescence . References Reflist Category Atomic, molecular, and optical physics nuclear stub ... more details
Proton emission also known as proton radioactivity is a type of radioactive decay in which a proton is ejected from a atomic nucleus nucleus . Image Zerfallsschema.png left thumb 300px The decay of a proton rich nucleus A populates excited states of a daughter nucleus B by emission or electron capture EC . Those excited states that lie below the separation energy for protons Sp decay by emission towards the groundstate of daughter B. For the higher excited states a competitive decay channel of proton emission to the granddaughter C exists, called delayed proton emission. Proton emission can occur from high lying excited states in a nucleus following a beta decay , in which case the process is known as beta delayed proton emission, or can occur from the ground state or a low lying nuclear isomer isomer of very proton rich nuclei, in which case the process is very similar to alpha decay . For a proton to escape a nucleus, the proton separation energy must be negative the proton is therefore unbound, and Quantum tunneling tunnels out of the nucleus in a finite time. Proton emission is not seen in naturally occurring isotopes proton emitters can be produced via nuclear reaction s, usually utilising some kind of particle accelerator . Although prompt i.e. not beta delayed proton emission was observed from an isomer in Cobalt Isotopes Cobalt 53 as early as 1969, no other proton emitting states were found until 1981, when the proton radioactive ground states of Lutetium Isotopes Lutetium 151 and Thulium Isotopes Thulium 147 were observed at experiments at the Gesellschaft f r Schwerionenforschung GSI in West Germany. Fact date December 2007 Research in the field flourished after this breakthrough, and to date more than 25 isotopes have been found to exhibit proton emission. The study of proton emission has aided the understanding of nuclear deformation, masses and structure, and it is a wonderfully pure example of quantum tunneling . In 2002, the simultaneous emission ... more details
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