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| [[Image:Deuterium Ionized.JPG|thumb|right|275px|A [[fusor]], doing nuclear fusion in '''star''' mode]]
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| '''Inertial electrostatic confinement''' is a branch of [[nuclear fusion|fusion]] research which uses an electric field to hold in a [[Plasma (physics)|plasma]]. Electric fields can do [[work (physics)|work]] on charged particles (either [[ions]] or [[electrons]]), heating them to fusion conditions.<ref name="elmore">WC Elmore et al, "On the Inertial-Electrostatic Confinement of a Plasma" ''Physics of Fluids'' '''2''', 239 (1959); {{doi|10.1063/1.1705917}} (8 pages) [http://pof.aip.org/resource/1/pfldas/v2/i3/p239_s1]</ref> This is typically done in a sphere, with material moving radially inward, but can also be done in a cylindrical geometry. The electric field can be generated using a wire grid <ref name = "Hirsch">Robert L. Hirsch, "Inertial-Electrostatic Confinement of Ionized Fusion Gases", Journal of Applied Physics, v. 38, no. 7, October 1967</ref> or a non-neutral plasma cloud.<ref name="Oct12013Paper">"Scaling law of electron confinement in a zero beta polywell device" Devid Gummershall, Matthew Carr, Scott Cornish, Physics of Plasma 20, 102701 (2013)</ref><ref name = "2013AussyWork">{{cite doi|10.1063/1.4804279}}</ref><ref>[http://opac.library.usyd.edu.au/record=b4663898~S4, "Electrostatic potential measurements and point cusp theories applied to a low beta polywell fusion device" PhD Thesis, Matthew Carr, 2013, The University of Sydney]</ref>
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| == Mechanism ==
| | The opportunity encounter at all for the restaurant, Kelly was shown to Teresa's dad. Instantly, Kelly caught a look into at her own dad. Simply serving coffee and exchanging several words and phraases achieved convinced Kelly: Here constitutes an man, an outstanding man, who dearly is motivated by his family. Teresa must meet my privately own Dad.<br><br>Go online for help. Practically any game has its obtain legion of devoted devotees, lots of which have countless hours crafting intensive maps and guides. Additionally there are newsgroups where you are speak one on one with other players. Benefit from this lottery jackpot and it is possible to eventually get past that level of cla you have been stuck on forever.<br><br>A single clash of clans hack equipment and tricks could be exceptionally handy in the labor that you are a keen player of the disruption. The finest hack apparatuses tackle just in regard to any doing work framework - Android and Fruit iOS. You also can exploit the obtain you can use on your apple iphone 3gs or Android telephones.<br><br>Obviously if you are searching with a particular game that would buy but want to assist you purchase it at the best price possible, consider the "shopping" tab readily available on many search magnetic motors. This will allow you to immediately equate the prices of our own game at all any major retailers online. You can also catch a glimpse of ratings for the insurer in question, helping you determine who you truly buy the game by means of.<br><br>Website is offering Clash along with Clans hack tool personal trainer to users who would like to. The website offering this tool is protected and it guarantees finest quality software. There furthermore other sites which deliver tool. If you liked this post and you would such as to receive even more information concerning [http://prometeu.net clash of clans triche] kindly check out our own web site. But take into account either incomplete or akin to bad quality. when users download these not complete hack tools, instead to complete well they end all the way up in trouble. So, players are advised pick the tool from an online site that offers complete shows.Users who are finding it tough to cross-stitching the hurdles can find a site that allows tourists to download the cheats. Most of the world-wide-web websites allow free download several websites charge fees. Users can locate a website from where they can obtain good quality software.<br><br>Your tutorial will guide you through your first few raids, constructions, and upgrades, sadly youre left to your own wiles pretty quickly. Your buildings take real time to construct and upgrade, your army units sensible choice recruit, and your useful resource buildings take time produce food and gold. Like all of his or her genre cousins, Throne Be quick is meant to took part in multiple short bursts in daytime. This type of fanatical gaming definitely works more beneficial on mobile devices which always with you and tend to send push notifications when timed tasks are completed. Then again, the success of so many hit Facebook games through the years indicates that people consult Facebook often enough to short play sessions execute there too.<br><br>Obviously individuals who produced this guidance Crack Clash of Family members are true fans related with the sport themselves, and as well this is exactly the things ensures the [http://www.dailymail.co.uk/home/search.html?sel=site&searchPhrase=potency potency] at our alternative, because experts needed to do it ourselves. |
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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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| === 1950's ===
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| [[File:Illustrations of various IEC concepts.png|thumbnail|This picture shows the anode/cathode design for different IEC concepts and experiments.]]
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| Three researchers at [[Los Alamos National Laboratory|LANL]] including, [[James L. Tuck|Jim Tuck]] first explored the idea, theoretically, in a 1959 paper.<ref name = "Elmore">"On Interial-electrostatic confinement of a plasma" Elmore, Tuck and Watson, Physics of Fluids, Volume 2, Number 3 June 1959</ref> The idea had been purposed by a colleague.<ref>W. H. Wells, Bendix Aviation Corporation (private communication, 1954)</ref> The concept was to capture electrons inside a positive cage. The electrons would accelerate the ions to fusion conditions.
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| Other concepts were being developed which would later merge into the IEC field. These include the publication of the [[Lawson criterion]] by [[John D. Lawson]] in 1957 in England.<ref>"Some Criteria for a Power producing thermonuclear reactor" John Lawson, Atomic Energy Research Establishment, Hanvell, Berks, 2nd November 1956</ref> This puts on minimum criteria on power plant designs which do fusion using hot maxwellian plasma clouds. Also, work exploring how electrons behave inside the [[Biconic cusp]], done by [[Harold Grad]] group at the [[Courant Institute]] in 1957.<ref>Grad, H. Theory of Cusped Geometries, I. General Survey, NYO-7969, Inst. Math. Sci., N.Y.U., December 1, 1957</ref><ref>Berkowitz, J., Theory of Cusped Geometries, II. Particle Losses, NYO-2530, Inst. Math. Sci., N.Y.U., January 6, 1959.</ref> A biconic cusp is a device with two alike magnetic poles facing one another (i.e. north-north). Electrons and ions can be trapped between these.
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| === 1960's ===
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| [[Image:US3386883 - fusor.png|thumb|upright=0.8|{{US patent|3,386,883}} - Schematic from Philo Farnsworth 1968 patent. This device has an inner cage to make the field, and four ion guns on the outside.]]
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| In his work with vacuum tubes, [[Philo Farnsworth]] observed that electric charge would accumulate in regions of the tube. Today, this effect is known as the [[Multipactor effect]].<ref>Cartlidge, Edwin. The Secret World of Amateur Fusion. Physics World, March 2007: IOP Publishing Ltd, pp. 10-11. ISSN: 0953-8585.</ref> Farnsworth reasoned that if ions were concentrated high enough they could collide and fuse. In 1962, he filed a patent on a design using a positive inner cage to concentrate plasma, in order to achieve nuclear fusion.<ref>US Patent 3,258,402 June 28, 1966</ref> During this time, [[Robert L. Hirsch]] joined the [[Philo Farnsworth|Farnsworth Television labs]] and began work on what became the [[fusor]]. Hirsch patented the design in 1966<ref>US Patent 3,386,883 June 4, 1968</ref> and published the design in 1967.<ref name = "Hirsch"/> The [[Robert L. Hirsch|Hirsch]] machine was a 17.8 cm diameter machine with 150 Kv voltage drop across it and used ion beams to help inject material.
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| Simultaneously, a key plasma physics text was published by [[Lyman Spitzer]] at [[Princeton University|Princeton]] in 1963.<ref>Lyman J Spitzer, "The Physics of Fully Ionized Gases" 1963</ref> Spitzer took the ideal gas laws and adopted them to an ionized plasma, developing many of the fundamental equations used to model a plasma. Meanwhile, [[Magnetic mirror]] theory and [[direct conversion]] was developed by [[Richard F. Post]]'s group at [[LLNL]].<ref>G. G. Kelley, Plasma Phys. 2, 503 (1967)</ref><ref name="Mirror Systems 1969">"Mirror Systems: Fuel Cycles, loss reduction and energy recovery" by Richard F. Post, BNES Nuclear fusion reactor conferences at Culham laboratory, September 1969.</ref> A magnetic mirror or magnetic bottle, is similar to a biconic cusp except that the poles are reversed.
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| === 1980's ===
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| In 1980 [[Robert W. Bussard]] developed a cross between a [[fusor]] and [[magnetic mirror]], the [[polywell]]. The idea was to confine a non-neutral plasma using magnetic fields. This would, in turn, attract ions. This idea had been published previously, notably by [[Oleg Lavrentiev]] in Russia.<ref>"Spherical Multipole Magnets for Plasma Research", Sadowsky, M., Rev.Sci.Instrum. 40 (1969) 1545</ref><ref>"Confinement d'un Plasma par un Systemem Polyedrique a' Courant Alternatif", Z. Naturforschung, Vol. 21 n, pp. 1085-1089 (1966)</ref><ref>"Electrostatic and Electromagnetic High-Temperature Plasma Traps", O.A.Lavrent’ev, Conference Proceedings, Electrostatic and Electromagnetic Confinement of Plasmas and the Phenomenology of Relativistic Electron Beams, Ann. N.Y. Acad. Sci. 251, (1975) 152-178</ref> Bussard patented <ref name="ReferenceA">R.W.Bussard in U.S.Patent 4,826,646, "Method and apparatus for controlling charged particles", issued May 2, 1989</ref> the design and received funding from [[Defense Threat Reduction Agency]], [[DARPA]] and, [[United States Navy|Navy]] to develop the idea.<ref>Dr. Robert Bussard (lecturer) (2006-11-09). "Should Google Go Nuclear? Clean, cheap, nuclear power (no, really)" (Flash video). Google Tech Talks. Google. Retrieved 2006-12-03.</ref>
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| === 1990's ===
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| Bussard and [[Nicholas Krall]] published theory and experimental results in the early nineties.<ref>Krall, N. A.; Coleman, M.; Maffei, K.; Lovberg, J.; Jacobsen, R.; Bussard, R. W. (1995). "Forming and maintaining a potential well in a quasispherical magnetic trap". Physics of Plasmas 2: 146.</ref><ref>"Inertial electrostatic fusion (IEF): A clean energy future" (Microsoft Word document). Energy/Matter Conversion Corporation. Retrieved 2006-12-03.</ref> In response, Todd Rider at [[MIT]], under [[Lawrence Lidsky]] developed general models of the device.<ref name="Plasma Physics 1995"/> Rider argued that the device was fundamentally limited. That same year, 1995, William Nevins at [[LLNL]] published a criticism of the [[polywell]].<ref>Nevins, William M. "Can Inertial Electrostatic Confinement Work beyond the Ion-ion Collisional Time Scale?" Physics of Plasmas 2.10 (1995): 3804-819. Print.</ref> Nevins argued that the particles would build up [[angular momentum]], causing the dense core to degrade.
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| In the mid-nineties, Bussard publications prompted the development of a [[fusor]]s at the [[University of Wisconsin–Madison]] and at the [[University of Illinois at Urbana–Champaign]]. Madison's machine was first built in 1995 and the group still produces some of the best IEC research in the world.<ref>http://iec.neep.wisc.edu/results.php "IEC Lab Timeline" accessed 1-25-2014</ref> Dr [[George H. Miley]] team at Illinois, built a 25 cm fusor which has produced 10E7 neutrons using deuterium gas <ref name="Physics Research 1999">"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> and discovered the "star mode" of fusor operation in 1994.<ref>Miley Abstract Accomplishments, www.avrc.com/Miley_abstract_accomplishments.doc</ref> The following year, the first "US-Japan Workshop on IEC Fusion", was conducted. This is now the premier conference for IEC researchers. At this time in Europe, an IEC device was developed as a commercial neutron source by [[DaimlerChrysler Aerospace|Daimler-Chrysler]] and ND fusion.<ref>http://www.nsd-fusion.com</ref><ref>"The IEC star-mode fusion neutron source for NAA--status and next-step designs". Appl Radiat Isot 53 (4-5): 779–83. October 2000.</ref> In the late nineties, hobbyist Richard Hull began building the first amateur [[fusor]]s in his home in Virginia.<ref name="youtube.com">"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 name="prometheusfusionperfection.com">"The Neutron Club", Richard Hull, Accessed 6-9-2011, http://prometheusfusionperfection.com/category/fusor/</ref> Hull and Paul Schatzkin, started fusor.net in 1998.<ref>http://www.fusor.net/</ref> Through this open forum, a community of amateur fusioneers have developed done nuclear fusion using homemade [[fusor]]s.
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| === 2000's ===
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| [[File:Taylor Wilson Presenting Fusor to Obama.jpg|thumb|Taylor Wilson presenting nuclear work to [[Barack Obama]], February 7, 2012<ref name="whitehouse">{{cite web|url=http://www.whitehouse.gov/blog/2012/02/07/president-obama-hosts-white-house-science-fair|title=President Obama Hosts the White House Science Fair|publisher=[[The White House]]|accessdate=October 18, 2013}}</ref>]]
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| In early 2000, Dr. Alex Klein, developed a cross between a polywell and ion beams.<ref name = "Mix">"The Multipole Ion-beam eXperiment", Presentation, Alex Klien, 7–8 December 2011, 13th US-Japan IEC workshop, Sydney 2011</ref> Using [[Dennis Gabor|Gabor lensing]] Dr. Klein attempted to focus plasma into non-nuetral clouds for fusion. He founded FP generation, which in April 2009, raised $3 million in financing from two venture funds.<ref>http://nextbigfuture.com/2011/05/fp-generation-fusion-project-was-funded.html, accessed: 1-25-2014, "FP generation funded"</ref><ref name="AlexPoster"/> The company developed the MIX and Marble machine, but ran into technical challenges and closed. In response to Riders' criticisms, researchers at [[LANL]] reasoned that a plasma oscillating could be at local thermodynamic equilibrium, this prompted the POPS and penning trap machines.<ref>"Equilibrium and low-frequency stability of a uniform density, collisionless, spherical Vlasov system" DC Barns, L Chacon, Physics of plasma November 2002</ref><ref name="ReferenceB">"Observation of Spherical Focus in an Electron Penning Trap", T. B. Mitchell and M. M. Schauer, PHYSICAL REVIEW LETTERS, VOLUME 78, NUMBER 1</ref> At this time, researchers at [[MIT]] became interested in [[fusor]]s for space propulsion<ref>Ph.D. Thesis "Improving Particle Confinement in Inertial Electrostatic Fusion for Spacecraft Power and Propulsion", Carl Dietrich, MASSACHUSETTS INSTITUTE OF TECHNOLOGY FEBRUARY 2007</ref> and powering space vehicles.<ref>Ph.D. Thesis "Improved lifetimes and synchronization behavior in Mutlt-grid IEC fusion devices", Tom McGuire,MASSACHUSETTS INSTITUTE OF TECHNOLOGY FEBRUARY 2007</ref> Specifically, researchers developed [[fusor]]s with multiple inner cages. In 2005, Greg Piefer graduated from Madison and founded [[Phoenix Nuclear Labs]] a company which developed the [[fusor]] into a neutron source for the mass production of medical isotopes.<ref name = "PNL">"Phoenix Nuclear Labs meets neutron production milestone", PNL press release May 1, 2013, Ross Radel, Evan Sengbusch</ref>
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| [[Robert Bussard]] began speaking openly about the Polywell in 2006.<ref>SirPhilip (posting an e-mail from "RW Bussard") (2006-06-23). "Fusion, eh?". James Randi Educational Foundation forums. Retrieved 2006-12-03.</ref> He attempted to generate interest <ref name = "Bussard6" >"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> in the research, before passing away from multiple myeloma in 2007, at the age of 79.<ref>M. Simon (2007-10-08). "Dr. Robert W. Bussard Has Passed". Classical Values. Retrieved 2007-10-09.</ref> His company was able to raise over ten million in funding from the US Navy in 2007,<ref>"Funding Continues for Bussard's Fusion Reactor". New Energy and Fuel. 2007-08-27. Note that this source is a blog and not necessarily reliable.</ref> 2008<ref>"A—Polywell Fusion Device Research, Solicitation Number: N6893609T0011". Federal Business Opportunities. October 2008. Retrieved 2008-11-07.</ref><ref>"A—Spatially Resolved Plasma Densities/Particle Energies, Solicitation Number: N6893609T0019". Federal Business Opportunities. October 2008. Retrieved 2008-11-07.</ref> and 2009.<ref>"Statement of work for advanced gaseous electrostatic energy (AGEE) concept exploration" (PDF). United States Navy. June 2009. Retrieved 2009-06-18.</ref> In 2008, [[Taylor Wilson]] achieved notoriety<ref>Dutton, Judy. "Teen Nuclear Scientist Fights Terror", CNN.com, September 1, 2011. Retrieved September 3, 2011.</ref><ref>"Rock Center: 19-year-old hopes to revolutionize nuclear power". NBC. Retrieved October 18, 2013.</ref> for achieving nuclear fusion at 14, with a homemade [[fusor]]. He presented this work at two [[TED (conference)|TED]] conferences,<ref>TED2013. "Taylor Wilson: My radical plan for small nuclear fission reactors". TED.com. Retrieved May 6, 2013.</ref><ref>"Good energy comes in small packages: Taylor Wilson at TED2013". TED.com. February 27, 2012.</ref> a [[USA Science and Engineering Festival|science fair]] hosted by the white house,<ref>"President Obama Hosts the White House Science Fair". The White House. Retrieved October 18, 2013.</ref> the [[Intel Science Talent Search]] and the [[Google Science Fair]].<ref>"The Boy Who Played With Fusion". Popular Science. Retrieved October 18, 2013.</ref>
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| === 2010's ===
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| Bussard's publications prompted the [[University of Sydney]] to start research into electron trapping in [[polywell]]s in 2010.<ref>Carr, M.; Khachan, J. (2010). "The dependence of the virtual cathode in a Polywell™ on the coil current and background gas pressure". Physics of Plasmas 17 (5): 052510. Bibcode:2010PhPl...17e2510C. doi:10.1063/1.3428744</ref> The group has explored theory,<ref>Carr, Matthew (2011). "Low beta confinement in a Polywell modeled with conventional point cusp theories". Physics of Plasma 18 (11).</ref> modeled devices,<ref name="Oct12013Paper"/> built devices, measured trapping <ref name="Carr, M. 2013">Carr, M.; Khachan, J. (2013). "A biased probe analysis of potential well formation in an electron only, low beta Polywell magnetic field". Physics of Plasmas 20 (5): 052504. Bibcode:2013PhPl...20e2504C. doi:10.1063/1.4804279</ref> and simulated trapping. These machines were all low power and cost and all had a small [[Beta (plasma physics)|beta]] ratio. In 2010, Carl Greninger founded the north west nuclear consortium, an organization which teaches nuclear engineering principles to high school students, using a 60 kvolt [[fusor]].<ref name="lobby.nwnc.us.com">http://lobby.nwnc.us.com/_layouts/15/start.aspx#/SitePages/Home.aspx</ref><ref name="ReferenceC">http://www.youtube.com/watch?v=KbeAcFy3ErM</ref> In 2012, Mark Suppes received attention,<ref>http://gizmodo.com/tag/mark-suppes</ref> in Brooklyn<ref>http://prometheusfusionperfection.com/</ref> for doing fusion with a fusor. Mark also measured electron trapping inside a [[polywell]]. Mr. Suppes was interviewed on CNN,<ref>http://www.cnn.com/2010/US/06/24/new.york.nuclear.hobby/</ref> and presented at 2012 [[Wired (magazine)|WIRED]] conference<ref>http://www.youtube.com/watch?v=Jvkoklpubiw</ref> and 2012 [[Lift Conference|lift]] conference. In 2013, the first IEC textbook was published by [[George H. Miley]].<ref>Inertial Electrostatic Confinement (IEC) Fusion, fundamentals and applications, ISBN 978-1-4614-9337-2 (Print) 978-1-4614-9338-9, published December 26th 2013</ref>
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| == Designs With Cage ==
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| === Fusor ===
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| [[Image:Homemade fusion reactor.JPG|thumb|upright=1.2|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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| The most well known IEC device is the [[Farnsworth-Hirsch Fusor|fusor]].<ref name = "Hirsch"/> This device typically consists of two wire cages inside a vacuum chamber. These cages are referred to as grids. The inner cage is held at a negative voltage against the outer cage. A small amount of [[Nuclear fuel#Fusion fuels|fusion fuel]] is introduced ([[deuterium]] gas being the most common). The voltage between the grids causes the fuel to ionize. The positive ions fall down the voltage drop towards the negative inner cage. As the accelerate, the [[electric field]] does [[Work (electrical)|work]] on the ions, heating them to fusion conditions. If these ions collide, they can fuse. Fusors can also use [[Particle accelerator|ion gun]]s rather than electric grids. [[Fusor]]s are popular with amateurs,<ref>http://www.fusor.net/, accessed 1-7-2014</ref> because they can be easy to construct, can regularly produce fusion and are a practical way to study [[nuclear physics]]. [[Fusor]]s have also been used as a commercial [[neutron generator]] for industrial applications.<ref>[http://www.nsd-fusion.com NSD-Gradel-Fusion]</ref>
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| No [[fusor]] has come close to producing a significant amount of [[fusion power]]. They can be dangerous if proper care is not taken because they require high voltages and can produce harmful radiation ([[neutrons]] and [[x-rays]]). Often, ions collide with the cages or wall. This [[Electrical conductor|conducts]] energy away from the device limiting its performance. In addition, collisions heat the grids, which limits high power devices. Collisions also spray high-mass ions into the reaction chamber, pollute the plasma and cool the fuel.
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| === POPS ===
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| Workers at [[Los Alamos National Laboratory|LANL]] identified that in [[Nonthermal plasma|non-thermal]] systems, the [[Coulomb collision|coulomb scattering]] cross section was larger than the fusion cross section.<ref>"Space charge neutralization in inertial electrostatic confinement plasmas" E. G. Evstatiev, R. A. Nebel, L. Chacón, J. Park, and G. Lapenta Phys. Plasmas 14, 042701 (2007)</ref> In response they built POPS,<ref>[http://link.aip.org/link/doi/10.1063/1.1888822 Periodically Oscillating Plasma Sphere (POPS)]</ref><ref name="park">J. Park et al., "Experimental Observation of a Periodically Oscillating Plasma Sphere in a Gridded Inertial Electrostatic Confinement Device," ''Phys. Rev. Lett.'' '''95,''' 015003, (2005) {{doi|10.1103/PhysRevLett.95.015003}} [http://link.aps.org/doi/10.1103/PhysRevLett.95.015003].</ref> a machine with a wire cage, where ions are moving at steady-state, or oscillating around. Such plasma can be at local thermodynamic equilibrium.<ref>D. C. Barnes and R. A. Nebel, Phys. Plasmas 5, 2498, 1998.</ref><ref>R. A. Nebel and D. C. Barnes, Fusion Technol. 38, 28, 1998.</ref> The ion oscillation is predicted to maintain the equilibrium distribution of the ions at all times, which would eliminate any power loss due to [[Coulomb collision|Coulomb scattering]], resulting in a [[net energy gain]]. This reactor concept becomes increasingly efficient as the size of the device shrinks. However, very high transparencies (>99.999%) are required for successful operation of the POPS concept. To this end S. Krupakar Murali et al., suggested that [[carbon nanotube]]s can be used to construct the cathode grids.<ref name="S. Krupakar Murali">S. Krupakar Murali et al.,"Carbon Nanotubes in IEC Fusion Reactors," ANS 2006 Annual Meeting, June 4–8, Reno, Nevada.</ref> This is also the first (suggested) application of carbon nanotubes directly in any fusion reactor.
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| == Designs With Fields ==
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| Several schemes attempt to combine [[Magnetic confinement fusion|Magnetic Confinement]] and [[electrostatics|electrostatic]] fields with IEC. The goal is to eliminate the inner wire cage of the [[fusor]], and the resulting problems.
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| ===Polywell ===
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| [[Image:Polywell WB-6 complete.jpg|thumb|upright=0.70| An example of a polywell's electromagnets]]
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| The [[polywell]] uses a magnetic field to trap electrons. When electrons or ions move into a dense field, they can be reflected by the [[magnetic mirror]] effect.<ref name="Mirror Systems 1969"/> A [[polywell]] is designed to trap electrons in the center, with a dense magnetic field surrounding them.<ref name="Carr, M. 2013"/><ref>"Vlasov-Poisson calculations of electron confinement times in Polywell(TM) devices using a steady-state particle-in-cell method". The DPP13 Meeting of The American Physical Society. Retrieved 2013-10-01.</ref><ref>"Electrostatic potential measurements and point cusp theories applied to a low beta polywell fusion device" PhD Thesis, Matthew Carr, 2013, The University of Sydney</ref> This is typically done using six electromagnets in a box. Each magnet is positioned so their poles face inward, creating a [[Null (physics)|null point]] in the center. The electrons trapped in the center form a "virtual electrode" <ref name="bussard">R.W. Bussard, "Some Physics Considerations of Magnetic Inertial-Electrostatic Confinement: A New Concept for Spherical Converging-flow Fusion," ''Fusion Technology'' '''19''', 273 (1991)</ref> Ideally, this electron cloud accelerates ions to fusion conditions.<ref name="ReferenceA"/>
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| ===Penning Trap===
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| A [[Penning trap]] uses both an electric and magnetic field to trap particles. A magnetic field to confine particles radially and a quadrupole electric field to confine the particles axially.<ref>http://www.ph.utexas.edu/~iheds/IntroductionPlasmaPhysics/375%20P%207%20(Penning).pdf</ref> In the 1990s, researchers at [[LANL]] build a penning trap to do fusion experiments. Their device (PFX) was a small (millimeters) and low power (one fifth of a Tesla, less than ten thousand volts) machine.<ref name="ReferenceB"/> The magnetic and electric fields are turned on. Electrons are emitted into the trap, caught and measured. Ideally, fusion schemes using Penning traps can hold in electrons which would then would attract ions, accelerating them to fusion conditions.<ref name="barnes">D.C. Barnes, R.A. Nebel, and L. Turner, "Production and Application of Dense Penning Trap Plasmas," ''Physics of Fluids'' '''B 5''', 3651 (1993)</ref>
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| ===Marble===
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| <!-- Deleted image removed: [[File:The multipole Ion-beam experiment magnet.png|thumbnail|upright=0.60|The electromagnet used in the MIX system.]] -->
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| MARBLE (which stood for: multiple [[Non-neutral plasmas|ambipolar]] recirculating beam line experiment) was a device which moved electrons and ions back and forth in a line.<ref name="AlexPoster">"The Multiple Ambipolar Recirculating Beam Line Experiment" Poster presentation, 2011 US-Japan IEC conference, Dr. Alex Klein</ref> Particle beams were reflected using [[electrostatic]] optics.<ref>"Dynamics of Ions in an Electrostatic Ion Beam Trap",http://www.weizmann.ac.il/conferences/frisno8/presentations05/thursday/Zajfman.pdf Presentation, Daniel Zajfman</ref> These optics made static voltage surfaces in free space{{citation needed|date=January 2014}}. Such surfaces reflect only particles with a specific kinetic energy, while higher-energy particles can traverse these surfaces unimpeded, although not unaffected. Electron trapping and plasma behavior was measured by [[Langmuir probe]].<ref name="AlexPoster"/> Marble kept ions on orbits that do not intersect grid wires—the latter also improves the space charge limitations by multiple nesting of ion beams at several energies.<ref>http://web.archive.org/web/*/www.beamfusion.org</ref> Researchers encountered problems with ion losses at the reflection points. Ions slowed down when turning, spending lots of time there, leading to high [[Electrical conductor|conduction]] losses.<ref>Alex Klein, in person interview, April 30, 2013</ref>
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| ===MIX===
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| The multipole ion-beam experiment (MIX) accelerated ions and electrons into a negatively charged electromagnet.<ref name = "Mix"/> Ions were focused using [[Dennis Gabor|Gabor lensing]]. Researcher had problems with a very thin ion turning region very close to a solid surface <ref name = "Mix"/> where ions could be conducted away.
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| == General Criticism ==
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| In 1995, Todd Rider critiqued all fusion power schemes using plasma systems at thermodynamic equilibrium.<ref name="Plasma Physics 1995">"Fundamental limitations on plasma fusions systems not in thermodynamic equilibrium" Thesis, Todd Rider, June 1995</ref> Rider assumed that if a plasma cloud at equilibrium have the following properties:
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| * They were [[Plasma (physics)|quasineutral]], where the positives and negatives are equally mixed together.<ref name="Plasma Physics 1995"/>
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| * They had evenly mixed fuel.<ref name="Plasma Physics 1995"/>
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| * They were [[Isotropy|isotropic]], meaning that its behavior was the same in any given direction.<ref name="Plasma Physics 1995"/>
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| * The plasma had a uniform energy and temperature throughout the cloud.<ref name="Plasma Physics 1995"/>
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| * The plasma was an unstructured Gaussian sphere.
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| Rider argued that if such as system was sufficiently heated, it could not be expected to produce net power, due to high [[Bremsstrahlung|x-ray]] losses.
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| Other fusion researchers such as [[Nicholas Krall]],<ref name = "krall">"The effect of collisions in maintaining a non Maxwellian plasma distribution in a spherically convergent ion focus", Rosenberg, N Krall, Physics of Fluids, 1992</ref> [[Robert W. Bussard]],<ref name="bussard"/> Norman Rostoker and Monkhorst disagreed with this assessment. They argue that the plasma conditions inside IEC machines are not quasineutral and have [[Plasma (physics)#Thermal vs. non-thermal plasmas|non-thermal]] energy distributions.<ref>[http://www.sciencemag.org/cgi/content/full/281/5375/307a Science 17 July 1998: Vol. 281. no. 5375, p. 307]</ref> Because the electron has a mass and diameter much smaller than the ion, the [[Electron temperature]] can be several orders of magnitude different then the ions. This may allow the plasma to be optimized, whereby cold electrons would reduce [[Radiation]] losses and hot ions would raise [[Nuclear fusion|Fusion]] rates.<ref name = "Bussard6"/>
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| === Thermalization ===
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| [[File:Thermalized Ion populations.jpg|thumbnail|This is an energy distribution comparison of thermalized and non-thermalized ions]]
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| The primary problem that Rider has raised is the thermalization of ions. Rider argued that, in a [[Plasma (physics)|quasineutral]] plasma where all the positives and negatives are distributed equally, the ions will interact. As they do, they exchange energy, causing their energy to spread out (in a [[Wiener process]]) heading to a bell curve (or [[Gaussian function]]) of energy. Rider focused his arguments within the ion population and did not address electron-to-ion energy exchange or [[Plasma (physics)#Thermal vs. non-thermal plasmas|non-thermal]] plasmas.
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| This spreading of energy causes several problems. One problem is making more and more cold ions, which are too cold to fuse. This would lower output power. Another problem is higher energy ions which have so much energy that they can escape the machine. This lowers fusion rates while raising conduction losses, because as the ions leave, energy is carried away with them.
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| === Radiation ===
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| Rider estimated that once the plasma is thermalized the [[Radiation]] losses would outpace any amount of [[Nuclear fusion|Fusion]] energy generated. He focused on a specific type of radiation: [[Bremsstrahlung|x-ray]] radiation. A particle in a plasma will radiate light anytime it speeds up or slows down. This can be estimated using the [[Larmor formula]]. Rider estimated this for D-T (deuterium-tritium fusion), D-D (deuterium fusion), and D-He3 (deuterium-helium 3 fusion), and that breakeven operation with any fuel except D-T is difficult.<ref name="Plasma Physics 1995"/>
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| === Core Focus ===
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| In 1995, Nevins argued that such machines would need to expend a great deal of energy maintaining ion focus in the center. The ions need to be focused so that they can find one another, collide and fuse. Overtime the positive ions and negative electrons would naturally intermix because of [[Electrostatic]] attraction. This causes the focus to be lost. This is core degradation. Nevins argued mathematically, that the fusion gain (ratio of fusion power produced to the power required to maintain the non-equilibrium ion distribution function) is limited to 0.1 assuming that the device is fueled with a mixture of [[deuterium]] and [[tritium]].<ref>[W.M. Nevins, Phys. Plasmas <2> (10), 3804 (October, 1995)]</ref>
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| The core focus problem was also identified in [[fusor]]s by Tim Thorson at the [[University of Wisconsin–Madison]] during his 1996 doctoral work.<ref name="Tim Thorson 1996"/> Charged ions would have some motion before they started accelerating in the center. This motion could be a twisting motion, where the ion had [[Angular momentum]], or simply a tangential velocity. This initial motion causes the cloud in the center of the [[fusor]] to be unfocused.
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| === Brillouin limit ===
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| In 1945, Columbia University professor Leon Brillouin, suggested that there was a limit to how many electrons one could pack into a given volume.<ref>L. Brillouin, Phys. Rev. 67, 260 (1945).</ref> This limit is commonly referred to as the Brillouin limited or Brillouin density,<ref>"Brillouin limit for electron plasmas confined on magnetic surfaces" Allen H. Boozer Department of Applied Physics and Applied Mathematics Columbia University, New York, NY 10027, http://www-fusion.ciemat.es/SW2005/abstracts/BoozerAH_SW.pdf</ref> this is shown below.<ref>"Observation of Spherical Focus in an Electron Penning Trap", T Mitchell and M. M. Schauer, PHYSICAL REVIEW LETTERS, VOLUME 78, NUMBER 1, VOLUME 78, NUMBER 1</ref>
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| :<math>N=\frac{B}{2*\mu_{0}*m*c^2}</math>
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| Where B is the magnetic field, <math>\mu_{0}</math> the permeability of free space, m the mass of confined particles, and c the speed of light. This may limit the charge density inside IEC devices.
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| == Commercial Applications ==
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| Since fusion reactions generates neutrons, the [[fusor]] has been developed into a neutron source.<ref>http://www.nsd-fusion.com/</ref> These neutron sources may be used to make products such as [[Isotopes of molybdenum|Molybdenum-99]]<ref name = "PNL"/> and [[Nitrogen-13]], medical isotopes, used for [[Positron emission tomography|PET]] scans.<ref>Talk. "Commercial Applications of IEC Devices" Web presentation, Preformed by Devlin Baker, December 3rd, 2013. http://sproutvideo.com/videos/189bd8bd131be6c290</ref>
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| ==Devices==
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| ===Government and Commercial===
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| * '''[[Los Alamos National Laboratory]]''' Researchers developed <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> POPS and penning trap <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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| * '''[[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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| * '''[[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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| * '''[[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 = "PNL"/>
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| * '''Energy Matter Conversion Inc''' Is a company in Santa Fe, which has developed large high powered polywell devices for the US Navy.
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| ===Universities===
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| * '''[[Tokyo Institute of Technology]]''' 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 several large devices, since 1995.<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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| * '''[[University of Illinois]]''' The fusion studies laboratory has built a ~25 cm fusor which has produced 10E7 neutrons using deuterium gas.<ref name="Physics Research 1999"/>
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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>
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| * '''[[University of Sydney]]''' Has built two low power, low [[Beta (plasma physics)|beta ratio]] [[polywell]]s. The first was constructed of Teflon rings and was about the size of a coffee cup. The second has ~12" diameter full casing, metal rings.
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| === Amateur ===
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| Amateurs mainly build fusors. Listed here are teams or machines which have produced neutrons
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|
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| * '''Richard Hull''' Since the late nineties, Richard Hull has built several fusors in his home in Richmond, Virginia.<ref name="youtube.com"/> In March 1999, he achieved a neutron rate of 10E5 neutrons per second.<ref name="prometheusfusionperfection.com"/> Hull maintains a list of amateurs who have gotten neutrons from fusors.
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| * '''North West Nuclear Consortium''' This is an organization in Washington state which teaches a class on nuclear engineering principles, to high school students, using a 60 kvolt fusor.<ref name="lobby.nwnc.us.com"/><ref name="ReferenceC"/>
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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''' Built a working fusor and measured electron trapping inside a 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.<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>
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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.
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| == See also ==
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| *[[Polywell]]
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| *[[Fusor]]
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| *[[Taylor Wilson]]
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| *[[List of fusion experiments]]
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| *[[Robert W. Bussard|Robert Bussard]]
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| * [[Philo Farnsworth]]
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| *[[List of plasma (physics) articles]]
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| *[[Phoenix Nuclear labs]]
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| ==Patents==
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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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| == References ==
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| {{reflist|2}}
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| == External links ==
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| *[http://iec.neep.wisc.edu/ University of Wisconsin-Madison IEC homepage]
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| **[http://fti.neep.wisc.edu/iec/IEC_Overview.pdf IEC Overview]
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| *From Proceedings of the 1999 Fusion Summer Study (Snowmass, Colorado):
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| **[http://www.ap.columbia.edu/SMproceedings/7.EmergingConcepts/7.Physics.pdf Summary of Physics Aspects of Some Emerging Concepts]
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| *[http://www.ap.columbia.edu/SMproceedings/11.ContributedPapers/11.Nadler.pdf Inertial-Electrostatic Confinement (IEC) of a Fusion Plasma with Grids]
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| *[http://www.americanscientist.org/template/AssetDetail/assetid/15723 Fusion from Television? (American Scientist Magazine, July-August 1999)]
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| *Talk by [[Robert W. Bussard|Dr. Robert Bussard]], former Asst. Director of the Atomic Energy Commission and founder of Energy Matter Conversion Corporation (EMC2):
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| **[http://video.google.com/videoplay?docid=1996321846673788606 Should Google Go Nuclear? Clean, cheap, nuclear power (no, really)] Google Tech Talk November 9, 2006.
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| *[http://cosmiclog.msnbc.msn.com/archive/2008/06/12/1136887.aspx Latest Fusion developments (WB-7 - June 2008) based on the work of Dr. Robert Bussard]
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| *[http://fpgeneration.com Website of FPGeneration, Inc]
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| *[http://thepolywellblog.blogspot.com/ The Polywell Blog ] Amateur blog about the Polywell
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| {{Fusion methods}}
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| {{Nuclear fusion reactors}}
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| {{DEFAULTSORT:Inertial Electrostatic Confinement}}
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| [[Category:Fusion power]]
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| [[de:Elektrostatischer Trägheitseinschluss]]
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