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| | I'm a 46 years old and working at the high school (Hotel Administration).<br>In my [http://Data.gov.uk/data/search?q=spare+time spare time] I try to [http://www.ehow.com/search.html?s=learn+French learn French]. I have been there and look forward to go there sometime near future. I like to read, preferably on my ebook reader. I like to watch The Big Bang Theory and Breaking Bad as well as documentaries about nature. I enjoy Hooping.<br><br>my weblog ... fifa 15 Coin generator ([http://www.ddhch.com/web/?document_srl=1816018&mid=DDHBulletin Www.ddhch.com]) |
| [[File:Homemade fusion reactor.JPG|thumb|upright=1.5|A homemade fusor.<ref>[http://www.tidbit77.blogspot.com/2010/02/fusion-reactors-first-light.html blogspot.com - Will's Amateur Science and Engineering: Fusion Reactor's First Light!], Feb 2010 (from [http://www.tidbit77.blogspot.com/search?updated-min=2010-01-01T00:00:00-08:00&updated-max=2011-01-01T00:00:00-08:00&max-results=14 blog])</ref>]]
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| A '''fusor''' is a device, that uses an [[electric field]] to heat [[ion]]s to conditions suitable for [[nuclear fusion]]. The machine has a voltage between two metal cages inside a vacuum. Positive ions fall down this voltage drop, building up speed. If they collide in the center, they can fuse. This is a type of [[Inertial electrostatic confinement]] device.
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| A Farnsworth–Hirsch fusor is the most common type of fusor.<ref name=Utah-bio>{{cite web | url = http://content.lib.utah.edu/u?/UU_EAD,2160 | title = Biography of Philo Taylor Farnsworth | publisher = University of Utah Marriott Library Special Collections | accessdate = 2007-07-05}}</ref> This design came from work by [[Philo T. Farnsworth]] in (1964) and [[Robert L. Hirsch]] in (1967).<ref name = "Hirsch">Robert L. Hirsch, "Inertial-Electrostatic Confinement of Ionized Fusion Gases", Journal of Applied Physics, v. 38, no. 7, October 1967</ref><ref>P. T. Farnsworth (private communication, 1964)</ref> A variant of fusor had been proposed previously by: William Elmore, [[James L. Tuck]], and Ken Watson at the [[Los Alamos National Laboratory]] <ref name = "Elmore">"On the Inertial Electrostatic Confinement of a Plasma" William Elmore, James Tuck and Ken Watson, The Physics of Fluids, January 30, 1959</ref> though they never built the machine.
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| Fusors have been built by various institutions. These include academic institutions such as the [[University of Wisconsin–Madison]],<ref>Ion Flow and Fusion Reactivity, Characterization of a Spherically convergent ion Focus. PhD Thesis, Dr. Timothy A Thorson, Wisconsin-Madison 1996.</ref> the [[Massachusetts Institute of Technology]]<ref>Improving Particle Confinement in Inertial electrostatic Fusion for Spacecraft Power and Propulsion. Dr. Carl Dietrich, PhD Thesis, the Massachusetts Institute of Technology, 2007</ref> and government entities, such as the [[Atomic Energy Organization of Iran]] and the [[Turkish Atomic Energy Authority]].<ref name = "Turkey">"Preliminary Results of Experimental Studies from Low Pressure Inertial Electrostatic Confinement Device" Journal of Fusion Energy, May 23, 2013</ref><ref>"Experimental Study of the Iranian Inertial Electrostatic Confinement Fusion Device as a Continuous Neutron Generator" V. Damideh, A. Sadighzadeh, Koohi, Aslezaeem, Heidarnia, Abdollahi, Journal of Fusion Energy, June 11, 2011</ref> Fusors have also been developed commercially, as sources for [[neutron]]s by [[DaimlerChrysler Aerospace]]<ref name ="DC"/> and as a method for generating medical isotopes.<ref name="May 1, 2013">"Phoenix Nuclear Labs meets neutron production milestone", PNL press release May 1, 2013, Ross Radel, Evan Sengbusch</ref><ref name="shinemed.com">http://shinemed.com/products/, SHINE medical inc, accessed 1-20-2014</ref><ref name="nsd-fusion.com">http://www.nsd-fusion.com</ref> Fusors have also become very popular for hobbyists and amateurs. A growing number of amateurs have done [[nuclear fusion]] using simple fusor machines.<ref>Hull, Richard. "The Fusor List." The Open Source Fusor Research Consortium II - Download Complete Thread. 58. Http://www.fusor.net/board/download_thread.php?site=fusor&bn=fusor_announce&thread=1022854449, 22 Mar. 2013. Web. 04 Apr. 2013</ref>
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| == Mechanism ==
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| For every [[volt]] that an ion is accelerated across, it gains 11,604 degrees Kelvin. For example, a typical [[magnetic confinement fusion]] plasma is 15 keV, or 170 megakelvin. An ion with a charge of one can reach this temperature by being accelerated across a fifteen thousand volt drop. In fusors, the voltage drop is made with a wire cage. Because most of the ions fall into the cage, fusors suffer from high [[Electrical resistivity and conductivity|conduction]] losses. Hence, no fusor has ever come close to break-even energy output.
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| [[File:Fusor Mechanism.png|thumb|center|400px|This is an illustration of the basic mechanism of fusion in fusors. (1) The fusor contains two concentric wire cages. The cathode is inside the anode. (2) Positive ions are attracted to the inner cathode. They fall down the voltage drop. The electric field does work on the ions heating them to fusion conditions. (3) The ions miss the inner cage. (4) The ions collide in the center and may fuse.<ref name="Tim Thorson 1996">"Ion flow and fusion reactivity characterization of a spherically convergent ion focus" Thesis work, Tim Thorson, December 1996, The University of Wisconsin–Madison</ref>]]
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| ==History==
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| [[Image:US3386883 - fusor.png|thumb|upright=1.0|{{US patent|3,386,883}} - fusor — Image from Farnsworths patent, on 4 June 1968, This device has an inner cage to make the field, and four ion guns on the outside.]]
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| ''See also, history of [[Inertial electrostatic confinement#History|IEC]]''
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| The fusor was originally conceived by [[Philo T. Farnsworth]], better known for his pioneering work in [[television]]. In the early 1930s, he investigated a number of [[vacuum tube]] designs for use in television, and found one that led to an interesting effect. In this design, which he called the “multipactor”, [[electron]]s moving from one [[electrode]] to another were stopped in mid-flight with the proper application of a [[high-frequency]] [[magnetic field]]. The charge would then accumulate in the center of the tube, leading to high amplification. Unfortunately it also led to high erosion on the [[electrode]]s when the electrons eventually hit them, and today the [[multipactor effect]] is generally considered a problem to be avoided.
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| What particularly interested Farnsworth about the device was its ability to focus electrons at a particular point. One of the biggest problems in [[fusion power|fusion research]] is to keep the hot fuel from hitting the walls of the container. If this is allowed to happen, the fuel cannot be kept hot enough for the [[Nuclear fusion|fusion reaction]] to occur. Farnsworth reasoned that he could build an [[electrostatic]] [[plasma equilibria and stability|plasma confinement]] system in which the "wall" fields of the reactor were electrons or ions being held in place by the ''multipactor''. Fuel could then be injected through the wall, and once inside it would be unable to escape. He called this concept a virtual electrode, and the system as a whole the ''fusor''.
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| ===Design===
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| Farnsworth's original fusor designs were based on cylindrical arrangements of electrodes, like the original multipactors. Fuel was ionized and then fired from small accelerators through holes in the outer (physical) electrodes. Once through the hole they were accelerated towards the inner reaction area at high velocity. Electrostatic pressure from the positively charged electrodes would keep the fuel as a whole off the walls of the chamber, and impacts from new ions would keep the hottest plasma in the center. He referred to this as [[inertial electrostatic confinement]], a term that continues to be used to this day.
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| ===Work at Farnsworth Television labs===
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| All of this work had taken place at the [[Philo Farnsworth|Farnsworth Television labs]], which had been purchased in 1949 by [[ITT Corporation]], as part of its plan to become the next [[RCA]]. However, a fusion research project was not regarded as immediately profitable. In 1965, the board of directors started asking Geneen to sell off the Farnsworth division, but he had his 1966 budget approved with funding until the middle of 1967. Further funding was refused, and that ended ITT's experiments with fusion.{{Citation needed|date=October 2009}}
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| Things changed dramatically with the arrival of [[Robert L. Hirsch|Robert Hirsch]], and the introduction of the modified Hirsch-Meeks fusor patent.{{citation needed|date=January 2012}} New fusors based on Hirsch's design were first constructed between 1964 and 1967.<ref name= "Hirsch" /> Hirsch published his design in a paper in 1967. His design included [[ion beam]]s to shoot ions into the vacuum chamber.<ref name= "Hirsch" />
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| The team then turned to the [[United States Atomic Energy Commission|AEC]], then in charge of fusion research funding, and provided them with a demonstration device mounted on a serving cart that produced more fusion than any existing "classical" device. The observers were startled, but the timing was bad; Hirsch himself had recently revealed the great progress being made by the Soviets using the [[tokamak]]. In response to this surprising development, the AEC decided to concentrate funding on large tokamak projects, and reduce backing for alternative concepts.{{Citation needed|date=October 2009}}
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| ===Recent developments===
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| In the early 1980s, disappointed by the slow progress on "big machines", a number of physicists took a fresh look at alternative designs. George H. Miley at the [[University of Illinois at Urbana-Champaign|University of Illinois]] picked up on the fusor and re-introduced it into the field. A low but steady interest in the fusor has persisted since. An important development was the successful commercial introduction of a fusor-based [[neutron generator]]. From 2006 until his death in 2007, [[Robert W. Bussard]] gave talks on a reactor similar in design to the Fusor, now called [[Polywell]], that he stated would be capable of useful power generation.<ref name="IAC2006">[http://www.askmar.com/ConferenceNotes/2006-9%20IAC%20Paper.pdf "The Advent of Clean Nuclear Fusion: Super-performance Space Power and Propulsion"], Robert W. Bussard, Ph.D., 57th International Astronautical Congress, October 2–6, 2006</ref> Most recently, the fusor has gained popularity among amateurs, who choose them as home projects due to their relatively low space, money, and power requirements. An online community of "fusioneers", The Open Source Fusor Research Consortium, or Fusor.net, dedicated to reporting developments in the world of fusors and aiding other amateurs in their projects. The site includes forums, articles and papers done on the fusor, including Farnsworth's original patent, as well as Hirsch's patent of his version of the invention.<ref>[http://fusor.net fusor.net]</ref>
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| ==Fusion in fusors== | |
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| === Basic fusion ===
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| [[File:Fusion rxnrate.svg|thumbnail|This is a plot of the cross section of different fusion reactions.]]
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| [[Nuclear fusion]] refers to reactions in which lighter [[atomic nucleus|nuclei]] are combined to become heavier nuclei. This process changes [[Mass–energy equivalence|mass into energy]] which in may be captured to provide [[fusion power]]. Many types of atoms can be fused. The easiest to fuse are [[deuterium]] and [[tritium]]. This happens when the ions have to have a temperature of at least 4 keV ([[kiloelectronvolt]]s) or about 45 million [[kelvin]]s. The second easiest reaction is fusing [[deuterium]] with itself. Because this gas is cheaper, it is the fuel commonly used by amateurs. The ease of doing a fusion reaction is measured by its [[cross section (physics)|cross section]].<ref>"Development of the indirect drive approach to inertial confinement fusion and the target physics basis for ignition and gain" John Lindl, Physics of Plasma, 1995</ref>
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| === Net power ===
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| At such conditions, the atoms are ionized and make a [[plasma (physics)|plasma]]. The energy generated by fusion, inside a hot plasma cloud can be found with the following equation.<ref name = "Lawson">"Some Criteria for a Power producing thermonuclear reactor" John Lawson, Atomic Energy Research Establishment, Hanvell, Berks, 2nd November 1956</ref>
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| :<math>P_\text{fusion} = n_A n_B \langle \sigma v_{A,B} \rangle E_\text{fusion}</math>
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| where:
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| * <math>P_\text{fusion}</math> is the fusion power density (energy per time per volume),
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| * ''n'' is the number density of species A or B (particles per volume),
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| * <math>\langle \sigma v_{A,B} \rangle</math> is the product of the collision cross-section ''σ'' (which depends on the relative velocity) and the relative velocity of the two species ''v'', averaged over all the particle velocities in the system, and
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| * <math>E_\text{fusion}</math> is the energy released by a single fusion reaction.
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| This equation shows that energy varies with the temperature, density, speed of collision, and fuel used. To reach net power, fusion reactions have to occur fast enough to make up for energy losses. Any power plant using fusion will hold in this hot cloud. Plasma clouds lose energy through [[Thermal conduction|conduction]] and [[radiation]].<ref name = "Lawson"/> Conduction is when [[ion]]s, [[electron]]s or [[neutral particle|neutrals]] touch a surface and leak out. Energy is lost with the particle. Radiation is when energy leaves the cloud as light. Radiation increases as the temperature rises. To get net power from fusion, you must overcome these losses. This leads to an equation for power output.
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| :<math>P_\text{out} = \eta_\text{capture}\left(P_\text{fusion} - P_\text{conduction} - P_\text{radiation}\right)</math>
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| where:
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| * ''η'', efficiency
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| John Lawson used this equation to estimate some conditions for net power <ref name = "Lawson"/> based on a [[Maxwell–Boltzmann distribution|Maxwellian]] cloud.<ref name = "Lawson"/> This is the [[Lawson criterion]]. Fusors typically suffer from [[Thermal conduction|conduction]] losses due to the wire cage being in the path of the recirculating plasma.
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| === In fusors ===
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| In the original fusor design, several small [[particle accelerator]]s, essentially TV tubes with the ends removed, inject ions at a relatively low voltage into a [[vacuum]] chamber. In the Hirsch version of the fusor, the ions are produced by ionizing a dilute gas in the chamber. In either version there are two concentric spherical [[electrode]]s, the inner one being charged negatively with respect to the outer one (to about 80 kV). Once the ions enter the region between the electrodes, they are accelerated towards the center.
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| In the fusor, the ions are accelerated to several keV by the electrodes, so heating as such is not necessary (as long as the ions fuse before losing their energy by any process). Whereas 45 megakelvins is a very high temperature by any standard, the corresponding voltage is only 4 kV, a level commonly found in such devices as [[neon light]]s and [[television]]s. To the extent that the ions remain at their initial energy, the energy can be tuned to take advantage of the peak of the reaction [[cross section (physics)|cross section]] or to avoid disadvantageous (for example neutron-producing) reactions that might occur at higher energies.
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| Various attempts have been made at increasing deuterium ionization rate, including heaters within "ion-guns", (similar to the "electron gun" which forms the basis for old-style television display tubes), as well as [[magnetron]] type devices, (which are the power sources for microwave ovens), which can enhance ion formation using high-voltage electro-magnetic fields. Any method which increases ion density (within limits which preserve ion mean-free path), or ion energy, can be expected to enhance the fusion yield, typically measured in the number of neutrons produced per second.
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| The ease with which the ion energy can be increased appears to be particularly useful when [[aneutronic fusion|"high temperature" fusion reactions]] are considered, such as [[proton]]-[[boron]]-11, which has plentiful fuel, requires no radioactive [[tritium]], and produces no neutrons in the primary reaction.
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| == Common considerations ==
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| ===Modes of operation===
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| [[Image:fusor running.jpg|thumb|upright=1.5|Farnsworth–Hirsch fusor during operation in so called "star mode" characterized by "rays" of glowing plasma which appear to emanate from the gaps in the inner grid.]]
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| Fusors have at least two modes of operation (possibly more): '''Star Mode''' and '''Halo Mode'''. Halo mode is characterized by a broad symmetric glow, with one or two electron beams exiting the structure. There is little fusion.<ref name ="Tim" >Thorson, Timothy A. Ion Flow and Fusion Reactivity Characterization of a Spherically Convergent Ion Focus. Thesis. Wisconsin Madison, 1996. Madison: University of Wisconsin, 1996. Print.</ref> The halo mode occurs in higher pressure tanks, and as the vacuum improves, the device transitions to star mode. Star mode appears as bright beams of light emanating from the device center.<ref name ="Tim" />
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| ===Power density===
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| Because the electric field made by the cages, is negative, it cannot simultaneously trap both positively charged ions and negative electrons. Hence, there must be some regions of [[Plasma (physics)#Potentials|charge accumulation]], which will result in an upper limit on the achievable density. This could place an upper limit on the machines power density, which may keep it too low for power production{{citation needed|date=September 2011}}.
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| ===Thermalization of the ion velocities===
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| When they first fall into the center of the fusor, the ions will all have the same energy, but the velocity distribution will rapidly approach a [[Maxwell-Boltzmann distribution]]. This would occur through simple [[Coulomb collision]]s in a matter of milliseconds, but beam-beam instabilities will occur orders of magnitude faster still. In comparison, any given ion will require a few minutes before undergoing a fusion reaction, so that the monoenergetic picture of the fusor, at least for power production, is not appropriate. One consequence of the thermalization is that some of the ions will gain enough energy to leave the potential well, taking their energy with them, without having undergone a fusion reaction.
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| ===Electrodes===
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| [[Image:Deuterium Ionized.JPG|thumb|right|250px|Image showing a different grid design]]
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| There are a number of unsolved challenges with the electrodes in a fusor power system. To begin with, the electrodes cannot influence the potential within themselves, so it would seem at first glance that the fusion plasma would be in more or less direct contact with the inner electrode, resulting in contamination of the plasma and destruction of the electrode. However, the majority of the fusion tends to occur in microchannels formed in areas of minimum electric potential,<ref>{{cite web|url=http://fti.neep.wisc.edu/pdf/fdm1267.pdf |title=UWFDM-1267 Diagnostic Study of Steady State Advanced Fuel (D-D and D-3He) Fusion in an IEC Device |format=PDF |date= |accessdate=2009-09-16}}</ref> seen as visible "rays" penetrating the core. These form because the forces within the region correspond to roughly stable "orbits". Approximately 40% of the high energy ions in a typical grid operating in star mode may be within these microchannels.<ref>http://www.mr-fusion.hellblazer.com/pdfs/study-of-ion-microchannels-and-iec-grid-effects-using-simion-code.pdf</ref> Nonetheless, grid collisions remain the primary energy loss mechanism for Farnsworth-Hirsch fusors. Complicating issues is the challenge in cooling the central electrode; any fusor producing enough power to run a power plant seems destined to also destroy its inner electrode. As one fundamental limitation, any method which produces a neutron flux that is captured to heat a working fluid will also bombard its electrodes with that flux, heating them as well.
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| Attempts to resolve these problems include [[Robert W. Bussard|Bussard]]'s [[Polywell]] system, D. C. Barnes' modified [[Penning trap]] approach, and the University of Illinois's fusor which retains grids but attempts to more tightly focus the ions into microchannels to attempt to avoid losses. While all three are IEC devices, only the last is actually a "fusor".
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| ===Radiation===
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| [[Nonrelativistic]] particles will radiate energy as light when they change speed.<ref>J. Larmor, "On a dynamical theory of the electric and luminiferous medium", Philosophical Transactions of the Royal Society 190, (1897) pp. 205–300 (Third and last in a series of papers with the same name)</ref> This loss rate can be estimated using the [[Larmor formula]]. Inside a fusor there is a cloud of [[ion]]s and [[electron]]s. These particles will accelerate or decelerate as they move about. These changes in speed make the cloud lose energy as light. The radiation from a fusor can (at least) be in the [[visible spectrum|visible]], [[ultraviolet]] and [[X-ray]] spectrum, depending on the type of fusor used. These changes in speed can be due to [[electrostatic]] interactions between particles (ion to ion, ion to electron, electron to electron). This is referred to '''[[bremsstrahlung]]''' radiation, and is common in fusors. Changes in speed can also be due to interactions between the particle and the electric field. Since there are no magnetic fields, fusors emit no [[Cyclotron radiation]] at slow speeds, or [[synchrotron radiation]] at high speeds.
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| In [http://hdl.handle.net/1721.1/11412 ''Fundamental limitations on plasma fusion systems not in thermodynamic equilibrium''], Todd Rider argues that a quasineutral isotropic plasma will lose energy due to [[Bremsstrahlung]] at a rate prohibitive for any fuel other than D-T (or possibly D-D or D-He3). This paper is not applicable to IEC fusion, as a quasineutral plasma cannot be contained by an electric field, which is a fundamental part of IEC fusion. However, in an earlier paper, [https://dspace.mit.edu/handle/1721.1/29869 "A general critique of inertial-electrostatic confinement fusion systems"], Rider addresses the common IEC devices directly, including the fusor. In the case of the fusor the electrons are generally separated from the mass of the fuel isolated near the electrodes, which limits the loss rate. However, Rider demonstrates that practical fusors operate in a range of modes that either lead to significant electron mixing and losses, or alternately lower power densities. This appears to be a sort of [[catch-22]] that limits the output of any fusor-like system.
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| ==Commercial Applications ==
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| {| class="infobox" style="text-align: left"
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| ! colspan="2" style="text-align:center; background:silver;"| Production source
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| |-
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| ! colspan=2 style="text-align: center" | [[Neutron]]s
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| |-
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| ! Energy
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| | 2.45 [[MeV]]
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| |-
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| ! Mass
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| | 940 [[MeV]]
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| |-
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| ! Electric charge
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| | 0 [[Coulomb|C]]
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| |-
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| ! Spin
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| | 1/2
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| |}
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| {{Main|Neutron generator}}
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| === Neutron Source ===
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| The fusor has been demonstrated as a viable [[neutron source]]. To date, the highest neutron flux achieved a fusor like device has been 3X10^11 neutrons per second with the deuterium-deuterium fusion reaction.<ref name="May 1, 2013"/> Typical fusors cannot reach fluxes as high as [[nuclear reactor]] or [[particle accelerator]] sources, but are sufficient for many uses. Importantly, the [[neutron generator]] easily sits on a benchtop, and can be turned off at the flick of a switch. A commercial fusor was developed as a non-core business within [[DaimlerChrysler Aerospace]] - Space Infrastructure, Bremen between 1996 and early 2001.<ref name ="DC" >{{cite journal|pmid=11003520 | volume=53 | issue=4-5 | title=The IEC star-mode fusion neutron source for NAA--status and next-step designs |date=October 2000 | journal=Appl Radiat Isot | pages=779–83}}</ref> After the project was effectively ended, the former project manager established a company which is called NSD-Fusion.<ref name="nsd-fusion.com"/>
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| === Medical isotopes ===
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| Commercial [[Phoenix Nuclear Labs|startups]] have used the neutron fluxes generated by fusors to generate [[Isotopes of molybdenum|Mo-99]] a isotope used for medical care.<ref name="May 1, 2013"/><ref name="shinemed.com"/>
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| ==Fusor examples==
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| ===Professional===
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| Fusors have been theoretically studied at multiple institutions, including: [[Kyoto University]],<ref>"Beam optics in inertial electrostatic confinement fusion", Review of Scientific instruments, Masami Ohnishi, Chikara Hoshino, Kiyoshi Yoshikawa, Kai Masuda, and Yasushi Yamamoto, VOLUME 71, NUMBER 2 FEBRUARY 2000</ref> and [[Kyushu University]].<ref>"Ion distribution function and radial pro�file of neutron production rate in spherical inertial electrostatic con�nement plasmas"H. Matsuura, T. Takaki, K. Funakoshi, Y. Nakao, K. Kudo, Nuclear Fusion, Vol. 40, No. 12, 2000</ref> Researchs meet annually at the US-Japan Workshop on Inertial Electrostatic Confinement Fusion. Listed here, are actual machines built.
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| * '''[[Tokyo Institute of Technology]]'''<ref name = "Turkey"/> has four IEC devices of different shapes: a spherical machine, a cylindrical device, a co-axial double cylinder and a magnetically assisted device.<ref>"Overview of IEC Research at Tokyo Tech." Eiki Hotta, 15th annual US-Japan IEC workshop, October 7th 2013, http://www.iae.kyoto-u.ac.jp/beam/iec2013/presentation/1-2.pdf</ref>
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| * '''[[University of Wisconsin-Madison]]''' A group at Wisconsin-Madison has been running a very large, funded, fusor program since 1991.<ref>R.P. Ashley, G.L. Kulcinski, J.F. Santarius, S.K. Murali, G. Piefer, 18th IEEE/NPSS Symposium on Fusion Engineering, IEEE #99CH37050, (1999)</ref>
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| * '''[[Turkish Atomic Energy Authority]]''' In 2013 this team built a 30 cm fusor at the Saraykoy Nuclear Research and Training center in Turkey. This fusor can reach 85 Kv and do deuterium fusion, producing 2.4E4 neutrons per second.<ref>"Preliminary Results of Experimental Studies from Low Pressure Inertial Electrostatic Confinement Device", A. S. B, Y. A, A. A, Journal of Fusion Energy, May 2013</ref>
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| * '''[[University of Illinois]]''' Dr. George Miley's team at the fusion studies laboratory has built a ~25 cm fusor which has produced 10E7 neutrons using deuterium gas.<ref>"A portable neutron/tunable X-ray source based on inertial electrostatic confinement", Nuclear Instruments and Methods in Physics Research, A 422 (1999) 16-20</ref>
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| * '''[[Atomic Energy Organization of Iran]]''' Researchers at Shahid Beheshti University in Iran have built a 60 cm diameter fusor which can produce 10E7 neutrons per second at 140 kilovolts using deuterium gas.<ref>"Experimental Study of the Iranian Inertial Electrostatic Confinement Fusion Device as a Continuous Neutron Generator" V. Damideh, Journal of Fusion Energy, June 11, 2011</ref>
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| * '''[[Los Alamos National Laboratory]]''' In the late nineties, researchers purposed <ref>"Stable, thermal equilibrium, large-amplitude, spherical plasma oscillations in electrostatic confinement devices", DC Barnes and Rick Nebel, PHYSICS OF PLASMAS VOLUME 5, NUMBER 7 JULY 1998</ref> and built a fusor-like system for oscillating plasma, inside a fusor. This device is known as the Periodically Oscillating Plasma Sphere or POPS.<ref>"Equilibrium and low-frequency stability of a uniform density, collisionless, spherical Vlasov system", D C Barnes, L Chacon and J M Finn, Physics Of Plasmas Volume 9, Number 11 November 2002</ref>
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| * '''[[Massachusetts Institute of Technology]]''' For his doctoral thesis in 2007, [[Terrafugia|Carl Dietrich]] built a fusor and studied its potential use in spacecraft propulsion.<ref>"Improving Particle Confinement in Inertial Electrostatic Fusion for Spacecraft Power and Propulsion" SUBMITTED TO THE DEPARTMENT OF AERONAUTICS AND ASTRONAUTICS, Carl Dietrich, February 2007</ref> In addition, [[High beta fusion reactor|Tom McGuire]] did his thesis<ref>"Improved Lifetimes and Synchronization Behavior in Multi-grid Inertial Electrostatic Confinement Fusion Devices", Feb 2007, MIT, DOCTOR OF PHILOSOPHY IN AERONAUTICS AND ASTRONAUTICS</ref><ref>"Numerical Predictions of Enhanced Ion Confinement in a Multi-grid IEC Device", McGuire, Sedwick, 44th AIAA/ASME/SAE/ASEE Joint Propulsion Conference & Exhibit 21–23 July 2008, Hartford, CT</ref> on fusors with multiple cages and ion guns.
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| * '''[[ITT Corporation]]''' [[Robert L. Hirsch|Hirschs]] original machine was a 17.8 cm diameter machine with 150 Kv voltage drop across it.<ref name = "Hirsch" /> This machine used ion beams.
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| * '''[[Phoenix Nuclear Labs]]''' Has developed a commercial neutron source based off a fusor, achieving 3X10^11 neutrons per second with the deuterium-deuterium fusion reaction.<ref name="May 1, 2013"/>
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| === Amateur ===
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| [[File:Taylor Wilson Presenting Fusor to Obama.jpg|thumbnail|Taylor Wilson presenting fusor work to Barack Obama, 2/7/2012]]
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| A number of amateurs have built working fusors and detected neutrons. Many fusor enthusiasts connect on forums <ref>http://www.fusor.net/</ref> and message boards online. Below are some examples of working fusors.
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| * '''Richard Hull''' Since the late nineties, Richard Hull has built several fusors in his home in Richmond, Virgina.<ref>"Living with a nuclear reactor" The Wall Street Journal, interview with Sam Schechner, http://www.youtube.com/watch?v=LJL3RQ4I-iE</ref> In March 1999, he achieved a neutron rate of 10E5 neutrons per second.<ref>"The Neutron Club", Richard Hull, Accessed 6-9-2011, http://prometheusfusionperfection.com/category/fusor/</ref> Hull maintains a list of amateurs who have gotten neutrons from fusors.
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| * '''Carl Greninger''' Founded the North West Nuclear Consortium,<ref>http://lobby.nwnc.us.com/_layouts/15/start.aspx#/SitePages/Home.aspx</ref> an organization in Washington state which teaches a class of a dozen high school students, nuclear engineering principles using a 60 kvolt fusor.<ref>http://www.youtube.com/watch?v=KbeAcFy3ErM</ref>
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| * '''[[Taylor Wilson]]''' In 2008, Taylor Wilson became the youngest person to build a working fusor, at age 14.<ref>Dutton, Judy. "Teen Nuclear Scientist Fights Terror", CNN.com, 1 September 2011. Retrieved 2011-09-03.</ref><ref>TED2012. "Taylor Wilson: Yup, I built a nuclear fusion reactor". TED.com. Retrieved 2013-04-14.</ref>
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| * '''Matthew Honickman''' Was a high school student who built a working fusor in his basement in Rochester, New York.<ref>"Building Electronics is teen's favorite leisure activity" Democrat and Chronicle, Ashwin Verghese, Jan 6th 2010</ref>
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| * '''Michael Li''' In 2003, Michael Li built a fusor and won second place <ref>Michael Li, Resume, Accessed 2013, http://www.princeton.edu/bcf/phd/students/link/Tianhui%20Michael%20Li.pdf</ref> in the US's [[Intel Science Talent Search]] winning a $75,000 college scholarship.<ref>http://prometheusfusionperfection.com/?s=Hull</ref>
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| * '''Mark Suppes''' A web designer for Gucci in Brooklyn New York, built a working fusor on a path to building the first amateur [[Polywell]].<ref>http://www.youtube.com/watch?v=Jvkoklpubiw, Mark Suppes Presentation at Wired 2012, October 2012</ref><ref>http://www.youtube.com/watch?v=Etlb43suCoc</ref>
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| * '''[[Thiago David Olson]]''' Built a 40 kV fusor at age 17, in his home in Rochester, Michigan and placed second in the [[Intel International Science and Engineering Fair]] in 2007.<ref>Teen builds basement nuclear reactor, Popular Science</ref><ref>Stephen Ornes: Radioactive Boy Scout, Discover Magazine, March 2007</ref><ref>“Neutron Activation Analysis Using an Inertial Electrostatic Confinement Fusion Reactor,” Thiago David Olson of Stoney Creek High School, Rochester Hills, MI AVS Newsletter, Fall 2007, page 3, 2007 Intel 58th International Science and Engineering Fair (ISEF)</ref>
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| * '''Andrew Seltzman''' Has built several fusors with neutrons detected in 2008.<ref>http://www.rtftechnologies.org/physics/fusor-mark3-test-runs.htm</ref> He is now a graduate student working on IEC at the [[University of Wisconsin–Madison]].
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| * '''Conrad Farnsworth''' of Newcastle, Wyoming produced fusion in 2011 at 17<ref>http://trib.com/lifestyles/home-and-garden/teen-makes-nuclear-reactor-in-dad-s-shed/article_e9576aa3-9df4-550a-9778-29c4843104ed.html</ref><ref>http://www.huffingtonpost.com/2013/02/04/conrad-farnsworth-builds-nuclear-fusion-reactor-garage_n_2616998.html</ref> and used this to win a regional and state science fair.
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| * '''Mert Soykan and Ferit Kutay''' built a 45 kV homemade fusor together in 2013 when they were both 16 years old and they are still working on ways to make their fusors more efficient by trying out new core designs such as thoroidal cores .
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| ==Patents==
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| * Bennett, W. H., {{US patent|3120475}}, February 1964. (Thermonuclear power)
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| * P.T. Farnsworth, {{US patent|3258402}}, June 1966 (Electric discharge — Nuclear interaction)
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| * P.T. Farnsworth, {{US patent|3386883}}. June 1968 (Method and apparatus)
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| * Hirsch, Robert, {{US patent|3530036}}. September 1970 (Apparatus)
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| * Hirsch, Robert, {{US patent|3530497}}. September 1970 (Generating apparatus — Hirsch/Meeks)
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| * Hirsch, Robert, {{US patent|3533910}}. October 1970 (Lithium-Ion source)
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| * Hirsch, Robert, {{US patent|3655508}}. April 1972 (Reduce plasma leakage)
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| * P.T. Farnsworth, {{US patent|3664920}}. May 1972 (Electrostatic containment)
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| * R.W. Bussard, "Method and apparatus for controlling charged particles", {{US patent|4826646}}, May 1989 (Method and apparatus — Magnetic grid fields).
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| * R.W. Bussard, "Method and apparatus for creating and controlling nuclear fusion reactions", {{US patent|5160695}}, November 1992 (Method and apparatus — Ion acoustic waves).
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| ==See also==
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| * [[Polywell]]
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| * [[Taylor Wilson]]
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| * [[Phoenix Nuclear Labs]]
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| * [[Philo Farnsworth]]
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| * [[Inertial electrostatic confinement]]
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| * [[Robert L. Hirsch]]
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| * [[Helium-3]] - possible fuel
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| * [[Lawson criterion]]
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| * [[Robert W. Bussard]]
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| * [[List of plasma (physics) articles]]
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| * [[Thiago David Olson]]
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| * [[High beta fusion reactor]]
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| ==References==
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| {{Reflist|2}}
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| ==Further reading==
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| {{Refbegin|2}}
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| * Reducing the Barriers to Fusion Electric Power; G.L. Kulcinski and J.F. Santarius, October 1997 Presented at "Pathways to Fusion Power", submitted to Journal of Fusion Energy, vol. 17, No. 1, 1998. ([http://solarsystem.estec.esa.nl/Moon2000/abs58_kulcinski.PDF Abstract] in [[Portable Document Format|PDF]])
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| * Robert L. Hirsch, "Inertial-Electrostatic Confinement of Ionized Fusion Gases", Journal of Applied Physics, v. 38, no. 7, October 1967
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| * [[Irving Langmuir]], [[Katharine B. Blodgett]], "Currents limited by space charge between concentric spheres" Physical Review, vol. 24, No. 1, pp49–59, 1924
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| * R. A. Anderl, J. K. Hartwell, J. H. Nadler, J. M. DeMora, R. A. Stubbers, and G. H. Miley, ''Development of an IEC Neutron Source for NDE,'' 16th Symposium on Fusion Engineering, eds. G. H. Miley and C. M. Elliott, IEEE Conf. Proc. 95CH35852, IEEE Piscataway, NJ, 1482–1485 (1996).
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| * "On the Inertial-Electrostatic Confinement of a Plasma" William C. Elmore, James L. Tuck, Kenneth M. Watson, "The Physics of Fluids" v. 2, no 3, May–June, 1959
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| * {{PDFlink|[http://fti.neep.wisc.edu/FTI/pdf/fdm1119.pdf D-3He Fusion in an Inertial Electrostatic Confinement Device]|142 KB}}; R.P. Ashley, G.L. Kulcinski, J.F. Santarius, S. Krupakar Murali, G. Piefer; IEEE Publication 99CH37050, pg. 35-37, 18th Symposium on Fusion Engineering, Albuquerque NM, 25–29 October 1999.
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| * G.L. Kulcinski, ''Progress in Steady State Fusion of Advanced Fuels in the University of Wisconsin IEC Device'', March 2001
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| * Fusion Reactivity Characterization of a Spherically Convergent Ion Focus, T.A. Thorson, R.D. Durst, R.J. Fonck, A.C. Sontag, Nuclear Fusion, Vol. 38, No. 4. p. 495, April 1998. ([http://www.iop.org/EJ/abstract/0029-5515/38/4/302 abstract])
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| * Convergence, Electrostatic Potential, and Density Measurements in a Spherically Convergent Ion Focus, T. A. Thorson, R. D. Durst, R. J. Fonck, and L. P. Wainwright, Phys. Plasma, 4:1, January 1997.
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| * R.W. Bussard and L. W. Jameson, "Inertial-Electrostatic Propulsion Spectrum: Airbreathing to Interstellar Flight", Journal of Propulsion and Power, v 11, no 2. The authors describe the proton — Boron 11 reaction and its application to ionic electrostatic confinement.
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| * R.W. Bussard and L. W. Jameson, "Fusion as Electric Propulsion", Journal of Propulsion and Power, v 6, no 5, September–October, 1990 (This is the same Bussard who conceived the Bussard Ramjet widely used in science-fiction for interstellar rocketry)
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| * Todd H. Rider, [https://dspace.mit.edu/handle/1721.1/29869 "A general critique of inertial-electrostatic confinement fusion systems"], M.S. thesis at [[MIT]], 1994.
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| * Todd H. Rider, [http://adsabs.harvard.edu/abs/1995PhDT........45R "Fundamental limitations on plasma fusion systems not in thermodynamic equilibrium"], Ph. D. thesis at [[MIT]], 1995.
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| * Todd H. Rider, [http://scitation.aip.org/getabs/servlet/GetabsServlet?prog=normal&id=PHPAEN000004000004001039000001&idtype=cvips&gifs=yes "Fundamental limitations on plasma fusion systems not in thermodynamic equilibrium"] Physics of Plasmas, April 1997, Volume 4, Issue 4, pp. 1039–1046.
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| * Could Advanced Fusion Fuels Be Used with Today's Technology?; J.F. Santarius, G.L. Kulcinski, L.A. El-Guebaly, H.Y. Khater, January 1998 [presented at Fusion Power Associates Annual Meeting, 27–29 August 1997, Aspen CO; Journal of Fusion Energy, Vol. 17, No. 1, 1998, p. 33].
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| * R.W. Bussard and L. W. Jameson, "From SSTO to Saturn's Moons, Superperformance Fusion Propulsion for Practical Spaceflight", 30th AIAA/ASME/SAE/ASEE Joint Propulsion Conference, 27–29 June 1994, AIAA-94-3269
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| * Robert W. Bussard presentation [http://video.google.com/videoplay?docid=1996321846673788606 video] to Google Employees — Google TechTalks, 9 November 2006.
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| * [http://www.askmar.com/ConferenceNotes/2006-9%20IAC%20Paper.pdf "The Advent of Clean Nuclear Fusion: Super-performance Space Power and Propulsion"], Robert W. Bussard, Ph.D., 57th International Astronautical Congress, 2–6 October 2006.
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| {{Refend}}
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| ==External links==
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| * David, Schneider, "[http://www.americanscientist.org/issues/pub/fusion-from-television Fusion from Television?]". [[American Scientist]], July–August
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| *[http://fti.neep.wisc.edu/iec/MainPage/ftisite1.htm University of Wisconsin-Madison IEC homepage]
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| *[http://www.rtftechnologies.org/ RTFTechnologies.org IEC Fusion Reactor ] Detailed IEC reactor construction information
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| *[http://mr-fusion.hellblazer.com/ Mr. Fusion — Blog of an experimenter]
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| *[http://mr-fusion.hellblazer.com/neutrons_for_sale.htm Neutrons for sale] — [[New Scientist]] article
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| *[http://www.wired.com/science/discoveries/news/2007/03/fusion_0329 Fusion Experiments Show Nuclear Power's Softer Side] — [[Wired (magazine)|Wired]] article
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| *[http://mr-fusion.hellblazer.com/pdfs/ Various Patents and Articles Related to Fusion, IEC, ICC and Plasma Physics]
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| *[http://www.belljar.net/634fusor.pdf How a Small Vacuum System and a Bit of Basketweaving Will Get You a Working Inertial-Electrostatic Confinement Neutron Source]
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| *[http://www.ibiblio.org/lunar/school/InterStellar/Explorer_Class/Bussard_Fusion_systems.HTML Description of Bussard's "aneutronic" boron version]
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| *[http://www.fusor.net Fusor.net] Forum for hobbyist fusor builders
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| *[http://www.nsd-fusion.com NSD-Fusion]
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| *[http://lobby.nwnc.us.com/_layouts/15/start.aspx#/SitePages/Home.aspx North West Nuclear Consortium] teachs high school students fusors
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| *[http://www.farnovision.com/chronicles/fusion/vassilatos.html ''The Farnsworth Fusor''] at the ''Farnsworth Chronicles'' (farnovision.com)
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| *[http://www.youtube.com/watch?v=4TkvPCMJEFI How-to: Making A Fusor in 60 minutes]
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| {{Fusion methods}}
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| {{Nuclear fusion reactors}}
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| [[Category:Fusion power]]
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| [[Category:Neutron sources]]
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| [[Category:Fusion reactors]]
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| [[Category:American inventions]]
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| [[Category:Plasma physics]]
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