# Fusor

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{{#invoke:Hatnote|hatnote}}

A homemade fusor.[1]

A fusor is a device that uses an electric field to heat ions 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.

A Farnsworth–Hirsch fusor is the most common type of fusor.[2] This design came from work by Philo T. Farnsworth (in 1964) and Robert L. Hirsch in 1967.[3][4] A variant of fusor had been proposed previously by William Elmore, James L. Tuck, and Ken Watson at the Los Alamos National Laboratory[5] though they never built the machine.

Fusors have been built by various institutions. These include academic institutions such as the University of Wisconsin–Madison,[6] the Massachusetts Institute of Technology[7] and government entities, such as the Atomic Energy Organization of Iran and the Turkish Atomic Energy Authority.[8][9] Fusors have also been developed commercially, as sources for neutrons by DaimlerChrysler Aerospace[10] and as a method for generating medical isotopes.[11][12][13] Fusors have also become very popular for hobbyists and amateurs. A growing number of amateurs have performed nuclear fusion using simple fusor machines.[14][15][16][17][18][19]

## Mechanism

For every volt that an ion of ±1 charge is accelerated across, it gains 11,604 kelvins in temperature. For example, a typical magnetic confinement fusion plasma is 15 keV, or 170 megakelvins. 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 wires of the cage, fusors suffer from high conduction losses. Hence, no fusor has ever come close to break-even energy output.

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.[20]

## History

U.S. 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.

See also, history of IEC

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", electrons 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 electrodes when the electrons eventually hit them, and today the multipactor effect is generally considered a problem to be avoided.

What particularly interested Farnsworth about the device was its ability to focus electrons at a particular point. One of the biggest problems in 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 fusion reaction to occur. Farnsworth reasoned that he could build an electrostatic 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.

### Design

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.

### Work at Farnsworth Television labs

All of this work had taken place at the 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.{{ safesubst:#invoke:Unsubst||date=__DATE__ |$B= {{#invoke:Category handler|main}}{{#invoke:Category handler|main}}[citation needed] }} Things changed dramatically with the arrival of Robert Hirsch, and the introduction of the modified Hirsch-Meeks fusor patent.{{ safesubst:#invoke:Unsubst||date=__DATE__ |$B= {{#invoke:Category handler|main}}{{#invoke:Category handler|main}}[citation needed] }} New fusors based on Hirsch's design were first constructed between 1964 and 1967.[3] Hirsch published his design in a paper in 1967. His design included ion beams to shoot ions into the vacuum chamber.[3]

### Thermalization of the ion velocities

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 collisions 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.

### Electrodes

File:Deuterium Ionized.JPG
Image showing a different grid design

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,[26] 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.[27] 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.

Attempts to resolve these problems include 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".

### Radiation

Nonrelativistic particles will radiate energy as light when they change speed.[28] This loss rate can be estimated using the Larmor formula. Inside a fusor there is a cloud of ions and electrons. 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, 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.

In 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, "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.

## Commercial Applications

Production source
Neutrons
Energy 2.45 MeV
Mass 940 MeV
Electric charge 0 C
Spin 1/2

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### Neutron Source

The fusor has been demonstrated as a viable neutron source. 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.[10] After the project was effectively ended, the former project manager established a company which is called NSD-Fusion.[13] To date, the highest neutron flux achieved by a fusor-like device has been 3 × 1011 neutrons per second with the deuterium-deuterium fusion reaction.[11]

### Medical isotopes

Commercial startups have used the neutron fluxes generated by fusors to generate Mo-99, an isotope used for medical care.[11][12]

## Fusor examples

### Professional

Fusors have been theoretically studied at multiple institutions, including: Kyoto University,[29] and Kyushu University.[30] Researchers meet annually at the US-Japan Workshop on Inertial Electrostatic Confinement Fusion. Listed here, are actual machines built.

• Tokyo Institute of Technology[8] has four IEC devices of different shapes: a spherical machine, a cylindrical device, a co-axial double cylinder and a magnetically assisted device.[31]
• University of Wisconsin-Madison A group at Wisconsin-Madison has been running a very large, funded, fusor program since 1991.[32]
• 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.[33]
• 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.[34]
• 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.[35]
• Los Alamos National Laboratory In the late nineties, researchers purposed[36] and built a fusor-like system for oscillating plasma, inside a fusor. This device is known as the Periodically Oscillating Plasma Sphere or POPS.[37]
• Massachusetts Institute of Technology For his doctoral thesis in 2007, Carl Dietrich built a fusor and studied its potential use in spacecraft propulsion.[38] In addition, Tom McGuire did his thesis[39][40] on fusors with multiple cages and ion guns.
• ITT Corporation Hirschs original machine was a 17.8 cm diameter machine with 150 Kv voltage drop across it.[3] This machine used ion beams.
• 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.[11]

### Amateur

Taylor Wilson presenting fusor work to Barack Obama, February 7, 2012

A number of amateurs have built working fusors and detected neutrons. Many fusor enthusiasts connect on forums[41] and message boards online. Below are some examples of working fusors.

• Richard Hull Since the late nineties, Richard Hull has built several fusors in his home in Richmond, Virginia.[42] In March 1999, he achieved a neutron rate of 10*105 neutrons per second.[43] Hull maintains a list of amateurs who have gotten neutrons from fusors.
• Carl Greninger Founded the North West Nuclear Consortium,[44] an organization in Washington state which teaches a class of a dozen high school students, nuclear engineering principles using a 60 kV fusor.[45]
• Taylor Wilson Taylor Wilson is the youngest person to build a working fusor, at age 14.[46][47]
• Matthew Honickman Was a high school student who built a working fusor in his basement in Rochester, New York.[48]
• Michael Li In 2003, Michael Li built a fusor and won second place[49] in the US's Intel Science Talent Search winning a $75,000 college scholarship.[50] • Mark Suppes A web designer for Gucci in Brooklyn New York, built a working fusor on a path to building the first amateur Polywell.[51][52] • 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.[53][54][55] • Andrew Seltzman Has built several fusors[56] with neutrons detected in 2008.[57] He is now a graduate student working on plasma physics at the University of Wisconsin–Madison. • Conrad Farnsworth of Newcastle, Wyoming produced fusion in 2011 at 17[58][59] and used this to win a regional and state science fair. ## Patents ## See also ## References 1. Template:Cite web 2. Robert L. Hirsch, "Inertial-Electrostatic Confinement of Ionized Fusion Gases", Journal of Applied Physics, v. 38, no. 7, October 1967 3. P. T. Farnsworth (private communication, 1964) 4. "On the Inertial Electrostatic Confinement of a Plasma" William Elmore, James Tuck and Ken Watson, The Physics of Fluids, January 30, 1959 5. Ion Flow and Fusion Reactivity, Characterization of a Spherically convergent ion Focus. PhD Thesis, Dr. Timothy A Thorson, Wisconsin-Madison 1996. 6. Improving Particle Confinement in Inertial electrostatic Fusion for Spacecraft Power and Propulsion. Dr. Carl Dietrich, PhD Thesis, the Massachusetts Institute of Technology, 2007 7. "Preliminary Results of Experimental Studies from Low Pressure Inertial Electrostatic Confinement Device" Journal of Fusion Energy, May 23, 2013 8. "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 9. {{#invoke:Citation/CS1|citation |CitationClass=journal }} 10. "Phoenix Nuclear Labs meets neutron production milestone", PNL press release May 1, 2013, Ross Radel, Evan Sengbusch 11. http://shinemed.com/products/, SHINE medical inc, accessed 1-20-2014 12. http://www.nsd-fusion.com 13. Hull, Richard. "The Fusor List." The Open Source Fusor Research Consortium II - Download Complete Thread. 58. http://fusor.net/board/viewtopic.php?t=13&f=7&sid=4d8521abbea0401b7c9ee0d4a6b09d6e#p512, 24 Apr. 2013. 14. http://discovermagazine.com/2010/extreme-universe/18-do-it-yourself-basement-fusion "How to Build a$1000 Fusion Reactor in Your Basement" Discovery Magazine March 2010
15. http://spectrum.ieee.org/energy/nuclear/fusion-on-a-budget "Fusion on a Budget" IEEE Specturm March 2009
16. http://www.bbc.co.uk/news/10385853 "Extreme DIY: Building a homemade nuclear reactor in NYC" BBC June 2010
17. http://robofusor.aditl.com/ "THE HAYLETT NUCLEAR FUSION PROJECT" Accessed 9/15/2014
18. http://www.cnet.com/news/13-year-old-builds-working-nuclear-fusion-reactor/ "13-year-old builds working nuclear fusion reactor" CNET news, March 2014
19. "Ion flow and fusion reactivity characterization of a spherically convergent ion focus" Thesis work, Tim Thorson, December 1996, The University of Wisconsin–Madison
20. "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
21. fusor.net
22. "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
23. "Some Criteria for a Power producing thermonuclear reactor" John Lawson, Atomic Energy Research Establishment, Hanvell, Berks, 2 November 1956
24. 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.
25. Template:Cite web
26. http://www.mr-fusion.hellblazer.com/pdfs/study-of-ion-microchannels-and-iec-grid-effects-using-simion-code.pdf
27. 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)
28. "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
29. "Ion distribution function and radial pro�file of neutron production rate in spherical inertial electrostatic confinement plasmas" H. Matsuura, T. Takaki, K. Funakoshi, Y. Nakao, K. Kudo, Nuclear Fusion, Vol. 40, No. 12, 2000
30. "Overview of IEC Research at Tokyo Tech." Eiki Hotta, 15th annual US-Japan IEC workshop, October 7, 2013
31. R.P. Ashley, G.L. Kulcinski, J.F. Santarius, S.K. Murali, G. Piefer, 18th IEEE/NPSS Symposium on Fusion Engineering, IEEE #99CH37050, (1999)
32. "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
33. "A portable neutron/tunable X-ray source based on inertial electrostatic confinement", Nuclear Instruments and Methods in Physics Research, A 422 (1999) 16-20
34. "Experimental Study of the Iranian Inertial Electrostatic Confinement Fusion Device as a Continuous Neutron Generator" V. Damideh, Journal of Fusion Energy, June 11, 2011
35. "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
36. "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
37. "Improving Particle Confinement in Inertial Electrostatic Fusion for Spacecraft Power and Propulsion" SUBMITTED TO THE DEPARTMENT OF AERONAUTICS AND ASTRONAUTICS, Carl Dietrich, February 2007
38. "Improved Lifetimes and Synchronization Behavior in Multi-grid Inertial Electrostatic Confinement Fusion Devices", Feb 2007, MIT, DOCTOR OF PHILOSOPHY IN AERONAUTICS AND ASTRONAUTICS
39. "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, Connecticut
40. http://www.fusor.net/
41. "Living with a nuclear reactor" The Wall Street Journal, interview with Sam Schechner, http://www.youtube.com/watch?v=LJL3RQ4I-iE
42. "The Neutron Club", Richard Hull, Accessed 6-9-2011, http://prometheusfusionperfection.com/category/fusor/
43. http://lobby.nwnc.us.com/_layouts/15/start.aspx#/SitePages/Home.aspx
44. http://www.youtube.com/watch?v=KbeAcFy3ErM
45. Dutton, Judy. "Teen Nuclear Scientist Fights Terror", CNN.com, 1 September 2011. Retrieved 2011-09-03.
46. TED2012. "Taylor Wilson: Yup, I built a nuclear fusion reactor". TED.com. Retrieved 2013-04-14.
47. "Building Electronics is teen's favorite leisure activity" Democrat and Chronicle, Ashwin Verghese, Jan 6th 2010
48. Michael Li, Resume, Accessed 2013, http://www.princeton.edu/bcf/phd/students/link/Tianhui%20Michael%20Li.pdf
49. http://prometheusfusionperfection.com/?s=Hull
50. http://www.youtube.com/watch?v=Jvkoklpubiw, Mark Suppes Presentation at Wired 2012, October 2012
51. http://www.youtube.com/watch?v=Etlb43suCoc
52. Teen builds basement nuclear reactor, Popular Science
53. Stephen Ornes: Radioactive Boy Scout, Discover Magazine, March 2007
54. "Neutron Activation Analysis Using an Inertial Electrostatic Confinement Fusion Reactor," Thiago David Olson of Stoney Creek High School, Rochester Hills, Michigan AVS Newsletter, Fall 2007, page 3, 2007 Intel 58th International Science and Engineering Fair (ISEF)
55. http://www.rtftechnologies.org/physics.htm
56. http://www.rtftechnologies.org/physics/fusor-mark3-test-runs.htm
57. http://trib.com/lifestyles/home-and-garden/teen-makes-nuclear-reactor-in-dad-s-shed/article_e9576aa3-9df4-550a-9778-29c4843104ed.html
58. http://www.huffingtonpost.com/2013/02/04/conrad-farnsworth-builds-nuclear-fusion-reactor-garage_n_2616998.html

## Further reading

• 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. (Abstract in PDF)
• Robert L. Hirsch, "Inertial-Electrostatic Confinement of Ionized Fusion Gases", Journal of Applied Physics, v. 38, no. 7, October 1967
• Irving Langmuir, Katharine B. Blodgett, "Currents limited by space charge between concentric spheres" Physical Review, vol. 24, No. 1, pp49–59, 1924
• 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, New Jersey, 1482–1485 (1996).
• "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
• D-3He Fusion in an Inertial Electrostatic Confinement Device PDF (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.
• G. L. Kulcinski, Progress in Steady State Fusion of Advanced Fuels in the University of Wisconsin IEC Device, March 2001
• 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. (abstract)
• 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.
• 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.
• 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)
• Todd H. Rider, "A general critique of inertial-electrostatic confinement fusion systems", M.S. thesis at MIT, 1994.
• Todd H. Rider, "Fundamental limitations on plasma fusion systems not in thermodynamic equilibrium", Ph. D. thesis at MIT, 1995.
• Todd H. Rider, "Fundamental limitations on plasma fusion systems not in thermodynamic equilibrium" Physics of Plasmas, April 1997, Volume 4, Issue 4, pp. 1039–1046.
• 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].
• 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
• Robert W. Bussard presentation video to Google Employees — Google TechTalks, 9 November 2006.
• "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.