Other uses Positron disambiguation Infobox Particle bgcolour name Positron antielectron image File PositronDiscovery.jpg 200px caption Cloud chamber photograph by C.D. Anderson of the first positron ever identified. A 6 mm lead plate separates the upper half of the chamber from the lower half. The positron ... Beta , SubatomicParticle Positron mass val 9.10938215 45 e 31 u kg ref name CODATA br ... CODATA color charge spin frac 1 2 num spin states The positron or antielectron is the antiparticle or the antimatter counterpart of the electron . The positron has an electric charge of 1e, a spin physics spin of , and has the same mass as an electron. When a low energy positron collides with a low ... electron positron annihilation . Positrons may be generated by positron emission radioactive decay ... Antimatter Dmitri Skobeltsyn first observed the positron in 1929. ref cite book author Frank ... Springer isbn 978 0387951751 ref Carl D. Anderson discovered the positron on August 2, 1932, ref ... 21 ref Anderson also coined the term positron . The positron was the first evidence of antimatter ... charge. The ion trail left by each positron appeared on the photographic plate with a curvature ... was positive. citation needed date August 2011 Anderson wrote in retrospect that the positron could ... and to search for new kinds of particles. Gamma rays, emitted indirectly by a positron emitting radionuclide tracer , are detected in positron emission tomography PET scanners used in hospitals ... Springer year 2006 isbn 0387323023 pages 2 3 ref An experimental tool called positron annihilation ..., or even voids, within a solid material. ref cite web title Introduction to Positron Research url http www.stolaf.edu academics positron intro.htm work St. Olaf College ref See also Beta particle Radioactive decay List of particles Positron emission tomography Positronium Proton Positronic brain ... is a Positron? from the Frequently Asked Questions Center for Antimatter Matter Studies http discover.positron.edu.au ... more details
A positron is an elementary particle of antimatter . Positron may also refer to Positron , a 1993 trance track by Cygnus X Positron bicycle shifting system from Shimano Positron City of Heroes , the comic video game character Positron emission , the radioactive decay Positronic brain , the fictional device conceived by Isaac Asimov Positron Public Safety Systems , a manufacturer of Enhanced 9 1 1 Telephone Systems Positron Records , the Chicago based independent record label Positron video game , the 1983 video game published by Micro Power Disambig ... more details
Nuclear physics Positron emission or beta plus decay Beta particle sup sup decay is a particular type of radioactive decay, called beta decay , in which a proton is converted to a neutron , and it releases a positron and a neutrino . Isotope s which undergo this decay and thereby emit positrons include carbon 11 , Isotopes of potassium potassium 40 , nitrogen 13 , Isotopes of oxygen oxygen 15 , fluorine 18 , and Isotopes of iodine iodine 121 . As an example, the following equation describes the beta plus decay of carbon 11 to boron 11, emitting a positron and a neutrino Autogenerated using Phykiformulae 0.12 User SkyLined Phykiformulae C 11 B 11 e ve 0.96 MeV border 0 style height 2em Nuclide Link carbon 11 Nuclide Link boron 11 SubatomicParticle link yes Positron SubatomicParticle link yes Electron Neutrino 0.96 electron volt MeV Inside protons and neutrons, there are fundamental particles called quark s. The two most common types of quarks are up quarks, which have a charge of sup 2 sup sub 3 sub and down quarks, with a sup 1 sup .... It is this that causes beta radiation. Positron emission happens when an up quark changes into a down quark. These isotopes are used in positron emission tomography , a technique used for medical ... by positron emission. Nuclei which decay by positron emission may also decay by electron capture . For low ... MeV, since the final state has an electron removed rather than a positron added. As the energy of the decay goes up, so does the branching ratio towards positron emission. However, if the energy difference is less than 2 m sub e sub c sup 2 sup , then positron emission cannot occur and electron ... for positron emission. External links Image Ndslivechart.png http www nds.iaea.org livechart The LIVEChart of Nuclides IAEA with filter on sup sup decay nuclear processes DEFAULTSORT Positron Emission ... ast Emisi n de positrones ca Emissi de positrons ko ms Pemancaran positron ja ... more details
Primarysources date December 2009 Notability companies date December 2009 infobox record label image Image Positron.gif 150px image bg black founded 1998 founder Chris Randall musician Chris Randall country United States of America U.S. location Chicago , Illinois genre Electronic music Electronic , Industrial rock url http www.positronrecords.com PositronRecords.com Positron Records is an independent record label based in Chicago , Illinois . The label was founded in 1998 in music 1998 by Chris Randall musician Chris Randall , frontman of the Industrial music industrial band Sister Machine Gun . Positron describes itself as an anti label because they release only a handful of albums and give as much support to each release as they can. ref http www.positronrecords.com posifaq.php Positron Records posiFAQ Bot generated title ref The label also features a Creative Commons licenses Creative Commons license for some of its albums, allowing individuals to upload those songs to peer to peer websites as well as Sampling music sample parts of those songs for private or commercial usage. ref http www.positronrecords.com cc index.php Positron Records Creative Commons Bot generated title ref Artists The Atomica Project Bizarbies Bounte Eco Hed Chris Randall musician Chris Randall under his own name and also as Micronaut S. Sturgis Scanalyzer Sister Machine Gun and spin off Amish Rake Fight Matt Walker drummer Matt Walker as Beautiful Assassins and also Impossible Recording Machine Label compilations Komposi001 Komposi002 Komposi003 See also List of record labels External links http www.positronrecords.com Official site MySpace positronrecords Positron Records References reflist Category Record labels established in 1998 Category Industrial record labels Category Electronic music record labels Category American independent record labels Category Companies based in Chicago, Illinois ... more details
Multiple issues orphan February 2009 context October 2009 Positron Lifetime Spectroscopy is a technique in material science used for studying the types and concentrations of atom ic sized defects in materials. Positron Sources Typically positron s are produced through Beta Decay . A typical source would be Sodium sup 22 sup Na, sodium 22 . Positron Behaviour in Materials Typically positron s will thermalize, slow down, very quickly in a material. This means that they barely penetrate the surface of most materials. After thermalization, the positron will diffuse around the material, interacting with any defects, Electromagnetism electromagnetic distortions or potential well s, they encounter. This may result in a change of the positron s state, collapsing its wave function and reducing the instantaneous chance of electron positron annihilation . This will change the characteristic lifetime in some ways similar to mean lifetime of the positron, which affects the lifetime spectra produced in experiment. Simulation Recently a program named SimPL has been produced at the University of Prince Edward Island , Prince Edward Island PEI , Canada , which attempts to simulate the positron interaction and model the output spectra. See also Positron Physics footer Category Materials science ... more details
Refimprove date December 2007 Positron Public Safety , an Intrado company, is a manufacturer of Enhanced 9 1 1 telephone systems as well as related public safety command and control equipment. They are based out of Montreal Montreal, Quebec, Canada , with regional offices in the United States. Positron Public Safety is a leading provider of 911 emergency telephone system throughout the Americas, with installations in Canada, the US, and Ecuador. External links http www.positron911.com Positron Public Safety Category Companies based in Montreal ... more details
merge Annihilation discuss Talk Electron positron annihilation Merge with annihilation date December 2009 Image Annihilation.png thumb Naturally occurring electron positron annihilation as a result of beta plus decay Image Feynman EP Annihilation.svg thumb Feynman diagram Feynman Diagram of Electron Positron Annihilation Electron positron annihilation occurs when an electron SubatomicParticle Electron and a positron SubatomicParticle Positron , the electron s antiparticle collide. The result of the collision is the annihilation of the electron and positron, and the creation of gamma ray photon s or, at higher energies, other particles SubatomicParticle Electron SubatomicParticle Positron &rarr SubatomicParticle Photon SubatomicParticle Photon The process must satisfy a number of conservation law s, including Charge conservation Conservation of electric charge . The net electric charge charge before and after is zero. Conservation of momentum linear momentum and total energy . This forbids the creation of a single gamma ray. However, in quantum field theory this process is allowed see Annihilation Examples of annihilation examples of annihilation . Conservation of angular momentum . As with any two charged objects, electrons and positrons may also ... equal to the rest energy of the electron or positron val 511 u keV . ref cite journal author W.B. ... it. However, no other such particles are known. High energy case If either the electron or positron ... yet produced by electron positron annihilation in particle accelerator s are W boson SubatomicParticle .... Practical uses This process is the physical phenomenon relied on as the basis of Positron Emission Tomography PET and Positron annihilation spectroscopy PAS . It is also used as a method of measuring ... positron creation, is a form of pair production governed by two photon physics . References reflist ... Electron Positron Annihilation Category Particle physics Category Nuclear medicine ar ... more details
one source date December 2010 Positron annihilation spectroscopy PAS ref Positrons in Solids, P. Hautojaervi, Topics in Current Physics 12 Springer Heidelberg 1979 ref or sometimes specifically referred to as Positron annihilation lifetime spectroscopy PALS is a non destructive spectroscopy technique to study voids and defects in solids. Condensed matter experiments The technique operates on the principle that a positron or positronium will annihilate through interaction with electrons. This annihilation releases gamma rays that can be detected the time between emission of positrons from a radioactive source and detection of gamma rays due to annihilation corresponds to the lifetime of positron or positronium. When positrons are injected into a solid body, they will interact in some manner with the electrons in that species. For solids containing free electrons such as metals or semiconductors , the implanted positrons will annihilate very rapidly unless voids such as vacancy defect s are present. If voids are available, positrons will reside in them and annihilate less rapidly than in the bulk of the material, on time scales up to 1 ns. For insulators such as polymers or zeolites , implanted positrons interact with electrons in the material to form positronium. Triplet positronium has a characteristic lifetime of 142 ns in vacuum in solids, this lifetime is reduced depending on the pore structure of the analyte similar to positrons, but on a larger size and time scale . Pore structure in insulators can be determined using the quantum mechanical Tao Eldrup model and extensions thereof. By changing the temperature at which a sample is analyzed, the pore structure can be fit to a model where positronium is confined in one, two, or three dimensions. However, interconnected ... pores. The experiment itself involves having a radioactive positron source often sup 22 sup Na ... stop signals are required , average positron or positronium lifetimes can be fit to a histogram ... more details
Infobox VG title Positron image Image Acorn Electron Positron screenshot.png 255px The first sheet, Acorn Electron version developer Gary Partis publisher Micro Power designer Gary Partis engine released 1983 genre Shoot em up modes Single player ratings platforms Acorn Electron , BBC Micro media Cassette requirements input Positron is a video game which was published for the BBC Micro and Acorn Electron computers by Micro Power in 1983. It was developed on a pre release Electron and was one of the few games other than those produced by Acornsoft available for the machine on its launch. Gameplay The player controls a laser base which can move left and right and fire vertically. The object of the game is to destroy all alien creatures on each screen, then proceed to the next. The first sheet of aliens follows the classic Space Invaders style of moving, that being left to right, then moving down one row before moving right to left. The standard Invaders strategy of picking off the end columns to stop a rapid descent also applies to the first sheet of Positron. This first sheet however is not representative of the rest of the game and serves only to lull the player into a false sense of security. All subsequent sheets follow a pseudo random formation, generally moving down the screen but at various speeds and with greatly varying levels of firepower for each individual enemy. This means the strategy must change to looking to find which enemies are descending fastest and picking them ... the previous laser bolt has either hit an alien or left the screen. Positron has no such limits ... game Arcadians a similar but more complex game takes more than twice as long to load. Author Positron ... caused by the lack of code . In the Summer of 1983, I wrote Positron in two days flat Electron version ... The spiritual sequel to Positron , the scrolling shooter Syncron 1987 , was also noted for its speed ... the speed of the game from the second sheet onwards. Positron is a fast moving, colourful and satisfying ... more details
Diagnostic infobox Name PAGENAME Image Caption ICD10 CH3 ICD9 MeshID OPS301 OtherCodes Positron emission mammography is a modality used to detect breast cancer . ref cite journal doi 10.2967 jnumed.109.064345 pmid 19759118 pmc 2873041 volume 50 issue 10 title Clinical imaging characteristics of the positron emission mammography camera PEM Flex Solo II year 2009 month October journal J. Nucl. Med. pages 1666 75 ref It is approved for patients with a history of breast cancer . ref name TartarComstock2008 cite book last1 Tartar first1 Marie last2 Comstock first2 Christopher E. last3 Kipper first3 Michael S. title Breast cancer imaging a multidisciplinary, multimodality approach url http books.google.com books?id 7VRF2Vvb4 UC&pg PA88 accessdate 18 July 2011 year 2008 publisher Elsevier Health Sciences isbn 9780323046770 pages 88 ref References reflist NCI cancer dict Category 2d nuclear medical imaging Category Breast imaging Category Cancer screening Oncology stub Breast procedures Medical imaging ... more details
Interventions infobox Name Positron Emission Tomography Image Caption ICD10 C?3 ICD9 ICD9proc 92.0 ICD9proc ... Image of a typical positron emission tomography PET facility File 16slicePETCT.jpg thumb 250px ... Positron emission tomography PET ref cite book title Positron Emission Tomography Basic Sciences last ... ?SGWID 0 102 24 0 0&searchType EASY CDA&queryText Positron Emission Tomography 3A Basic Sciences ... in the body. The system detects pairs of gamma ray s emitted indirectly by a positron emitting radionuclide ... and others at Washington University School of Medicine . ref cite journal title A positron emission ... of annihilation radiation for medical imaging. ref cite journal title Localization of brain tumors with positron ... most responsible for the acceptance of positron imaging was the development of radiopharmaceuticals ... demonstrated the concentration of FDG in that organ. Later, the substance was used in dedicated positron tomographic scanners, to yield the modern procedure. The logical extension of positron instrumentation ... lived radioisotopes and positron detection in Proceedings of the Symposium on Dynamic Studies with Radioisotopes ... Y.L., 32 Crystal positron transverse section detector , in Tomographic Imaging in Nuclear Medicine ... Cho ref CHO, Z. H., ERIKSSON L., and CHAN J.K., A circular ring transverse axial positron camera in Reconstruction ... acquisition process As the radioisotope undergoes positron emission decay also known as positive beta decay , it emits a positron, an antiparticle of the electron with opposite charge. The emitted positron ... ref The encounter annihilates both electron and positron, producing a pair of electron positron annihilation ... pairs i.e. within a timing window of a few nanoseconds are ignored. Localization of the positron annihilation event The most significant fraction of electron positron decays result in two 511 keV ... in April 2009 a 9.4 Tesla unit tesla magnetic resonance tomograph MRT combined with a positron emission ... with fluorine 18. Due to the short half lives of most positron emitting radioisotopes, the radiotracers ... more details
Diagnostic infobox Name PAGENAME Image Caption PET scan of a normal 20 year old brain. ICD10 C030 ICD9 MeshID OPS301 OtherCodes Positron emission tomography PET measures emissions from radioactively labeled metabolically active chemicals that have been injected into the bloodstream. The emission data are computer processed to produce multi dimensional images of the distribution of the chemicals throughout the brain. ref Lars Goran Nilsson and Hans J. Markowitsch 1999 . Cognitive Neuroscience of Memory . Seattle Hogrefe & Huber Publishers., page 57 ref Process The positron emitting radioisotope s used are usually produced by a cyclotron , and chemicals are labeled with these radioactive atoms. The labeled compound, called a radiotracer , is injected into the bloodstream and eventually makes its way to the brain through blood circulation. Detectors in the PET scanner detect the radioactivity as the compound accumulates in various regions of the brain. A computer uses the data gathered by the detectors to create multi dimensional normally 3 dimensional volumetric or 4 dimensional time varying images that show the distribution of the radiotracer in the brain. Especially useful are a wide array of ligands used to map different aspects of neurotransmitter activity, with by far the most commonly used PET tracer being a labeled form of glucose see Fluorodeoxyglucose 18F FDG . Advantages and disadvantages The greatest benefit of PET scanning is that different compounds can show blood flow and oxygen and glucose metabolism in the tissues of the working brain. These measurements reflect the amount of brain activity in the various regions of the brain and allow to learn more about how the brain works. PET scans were superior to all other metabolic imaging methods in terms of resolution and speed of completion as little as 30 seconds , when they first became available. The improved resolution permitted better study to be made as to the area of the brain activated by a particular ... more details
The Beijing Electron Positron Collider II BEPC II is an electron positron collider , a type of particle accelerator . Located in China, it has been in operation since 2008 and consists a Circular construction, 240m in circumference. Electron energy 3.7 GeV Positron energy 3.7 GeV BES III The BES III Beijing Spectrometer III is the main detector ref http www.hep.umn.edu bes3 Minnesota BES III home page ref for the upgraded BEPC II. BES III uses a large superconducting solenoid the most powerful magnet in China Citation needed date July 2010 to provide a 1 tesla magnetic field, and also features a helium gas based tracking chamber and a calorimeter using 6240 caesium iodide crystals. See also Large Electron Positron Collider Electron positron annihilation References reflist Category Particle physics facilities Category Particle experiments zh ... more details
511 can mean The year 511 A.D. The telephone number 5 1 1 511 , used for transportation information in many regions of the United States 511 KeV , the energy of each of the two photons created when a positron and an electron Electron positron annihilation annihilate Numberdis az 511 d qiql dirm it 511 disambigua ht 511 menm non ... more details
PALS may refer to Pouch Attachment Ladder System Pediatric Advanced Life Support Periarteriolar lymphoid sheaths Asterix IV laser Prague Asterix Laser System Patient Advice and Liaison Service Positron annihilation spectroscopy Positron Annihilation Lifetime Spectroscopy See also PAL disambiguation disambig Long comment to avoid being listed on short pages ... more details
Michael Phelps is a swimmer. Michael Phelps may also refer to Michael E. Phelps , co developer of Positron emission tomography Mike Phelps , basketball player hndis name Phelps, Michael ... more details
Electron Pair Production may refer to Cooper pair Cooper pairing of electrons in superconductor Electron positron pair production Carrier generation and recombination Electron hole pair generation in semiconductor Electron pair Pairing of electrons on the same atomic or molecular orbital Disambig ... more details
Adventure Komposi001 2002 Positron Records Damage and Bang Bang Fully Operational Mix Komposi002 2003 Positron Records I Don t Need and To Hell With You Christ Analogue Remix Komposi003 2006 Positron ... Technique SMG 6.0 Record Release Show VCD, 2001 Positron Records SMG 6.5 Record Release Show DVD, 2002 Positron Records Sister Machine Gun Industrial music footer Category Discographies of musicians ... more details
The term SUV normally refers to sport utility vehicle s. It can also refer to Standardized Uptake Value , a measure used in Positron Emission Tomography for quantification Liposome Small unilamellar vesicle , a liposome with a single lipid bilayer disambig Category Initialisms de SUV Begriffskl rung fr SUV homonymie it SUV disambigua ... more details
A pair conversion instrument detects high energy gamma rays by providing an environment generally a thin foil of dense metal, commonly tungsten in which they tend to generate electron positron pairs, and then using standard particle physics techniques such as a microstrip detector to detect these particles. Usually there are several stacks of conversion foils and particle detectors placed on top of one another, so that the electron positron pairs can be tracked as they pass through consecutive detectors and at the bottom of the stack one commonly finds a calorimeter particle physics calorimeter capable of measuring the energy of the electron and the positron and inferring the energy of the incoming gamma ray. An anticoincidence shield of some kind is needed so that charged particles entering the device from outside are not confused with electron positron pairs generated in the conversion foils. One of the larger operational pair conversion telescopes is the Large Area Telescope on Gamma ray Large Area Space Telescope GLAST . Space based pair conversion detectors tend to make for rather expensive missions, since they unavoidably contain several hundred kilograms of lead or tungsten. http cosmology.berkeley.edu inpac inpac retreat slides Hiroshima 3 9.pdf has a slide illustrating the design of LAT. Category Photonics ... more details
DAPP may stand for In spaceflight, the Data Acquisition and Processing Program, later renamed the Defense Meteorological Satellite Program . In positron emission tomography, a compound used as a radioligand that binds to the serotonin transporter . Dimensional Assessment of Personality Pathology DAPP , a psychological assessment instrument measuring 18 personality traits that provide a systematic representation of personality disorder. disambig ... more details
Molecular breast imaging can refer to Scintimammography Positron emission mammography disambig Short pages monitor This long comment was added to the page to prevent it from being listed on Special Shortpages. It and the accompanying monitoring template were generated via Template Long comment. Please do not remove the monitor template without removing the comment as well. ... more details
Interventions infobox Name Emission computed tomography Image Caption ICD10 ICD9 ICD9proc 92.0 ICD9proc 92.1 MeshID D014055 OPS301 OPS301 3 72 OPS301 3 75 OtherCodes Emission computed tomography is a type of tomography involving radioactive emissions. Types include positron emission tomography PET and Single photon emission computed tomography SPECT . The imaging agent used in SPECT emits gamma rays , as opposed to the positron emitters such as sup 18 sup F used in PET. There are a range of radiotracers such as sup 99m sup Tc, sup 111 sup In, sup 123 sup I, sup 201 sup Tl that can be used, depending on the specific application. Medical imaging medicine stub Category Tomography Category 3d nuclear medical imaging ... more details
Orphan date April 2012 Refimprove date December 2009 VEPP 2000 Lang ru 2000 is an upgrade of the former VEPP 2M electron positron collider particle accelerator currently under construction at Budker Institute of Nuclear Physics BINP in Novosibirsk , Siberia , Russia . ref name kooparxiv cite arxiv eprint physics 0106013 ref ref name vepp2khome http vepp2k.inp.nsk.su VEPP 2000 homepage Russian and English ref References reflist DEFAULTSORT Vepp 2000 Category Particle physics facilities Accelerator stub ru 2000 ... more details
correct title reason namespace iS internal section Unreferenced stub auto yes date December 2009 Infobox VG title iS internal section image File Internal section fore.jpg 256px developer Positron disambiguation positron publisher Square Co., Ltd. designer composer Shinji Hosoe br Ayako Saso engine released Vgrelease JP January 28, 1999 genre Shooter game Shooter , Music game music modes Single player ratings platforms PlayStation console PlayStation media 1 CD ROM requirements input Game controller DISPLAYTITLE iS internal section Nihongo iS internal section is a video game developed by Positron disambiguation Positron and published by Square Co. Square and released in 1999 in video gaming 1999 . In the same vein of gameplay as Tempest 2000 , iS internal section is a Shoot 27em up Tube shooters tube shooter , a type of shoot em up where the player controls a ship looking down a long tunnel or tube, and the player can move around inside the cylinder, shooting enemies that it runs into while moving. It is an experimental project that responds to its 16 built in tracks, or even your own music from a CD. DEFAULTSORT Is Internal Section Category 1999 video games Category Fixed shooters Category Japan exclusive video games Category Music generated games Category Music video games Category PlayStation games Category PlayStation only games Category Square company games shmup videogame stub ja IS internal section ... more details
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