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The refs of course trace back to you, then from there to Todd Ritter. I am curious about what was wrong, the problem as a whole, or the explaination of why it happened? Or has something happened to fundamentally change his conclusions?
Maury 5 July 2005 21:42 (UTC)
The text I reverted is this:
My objections are
That seemed like enough reasons for a revert. Rider made two points, one that the bremsstrahlung losses for advanced fuels (which are often but not necessarily connected with IEC) are too large for a reasonable energy balance. This is covered under Nuclear_fusion#Bremsstrahlung_losses. The other point (his really creative contribution) is that a non-Maxwellian distribution requires infeasibly large recirculating power. This point is covered, albeit briefly, in Farnsworth-Hirsch_Fusor#Thermalization_of_the_ion_velocities (and is mangled in the articles on Fusion rocket and Cold fusion). We could discuss, if you like, whether other places are more appropriate for this information, or whether it should be expanded or duplicated. Art Carlson 2005 July 6 07:16 (UTC)
Ok, back to you now...
1) I am unaware of any IEC system in which the fuel is not being continually showered into the interior. I suppose if one could create a system with a high enough containment time it might be possible, but I can't even see people suggesting this. Are you being overly piquane here, or do you really feel that a long-containment system is a real possibility, and that in such a system Ritter's concerns will not hold?
2) I am not sure what you mean here. Under the fusor the new ions arriving via acceleration are at a higher energy than the average within the containment area. Fusion products are likewise. As I understand it, generally there is a lot of fairly cool fuel and a small number of much higher temperature fuel. Is this not the case?
3) If (2) is correct the acceleration seen by the typical high-speed particle will be much geater on average. Under an equilibrium system the average particle will generally interact with one of roughly the same energy (given a distribution, of course). Under a non-equilibrium system it will generally interact with one that is much cooler.
4) See (3).
5) Yes
If I have scrambled the two (bremsstrahlung vs recirculation), then considering that the second of his points is still valid for all known IEC approaches, shouldn't that be placed in this article? Even a short note, pointing back to the link you provided would seem appropriate.
As to the other articles, I'm all for removing the content from it entirely. It certainly has nothing to do with fusion rockets, and I can't imagine why anyone would care to read about it in a cold fusion article. In fact, I think I'll go edit them now.
Maury 6 July 2005 12:00 (UTC)
The mention at the end of cold fusion may be out of place, I suppose, but it doesn't seem to read that way. I don't see the mention in fusion rocket any more.
Maury 6 July 2005 12:47 (UTC)
I'm still worried about the realistic limit on the electric field strength at the surface of the electrodes. In the article I assumed the 230 MV/m needed to compare with a tokamak was out of the question and that 1 MV/m was already "generous". But several sources (e.g. [1]) mention a field of 25 GV/m on the tungsten electrode in pyroelectric fusion. Am I being to hard on IEC? On the other hand, we always tried to avoid voltages above 100 V when using Langmuir probes because otherwise we would get arcs. 100 V/mm is only 0.1 MV/m. Art Carlson 12:42, 2005 July 22 (UTC)
80% of the fusion energy produced in a DT cycle comes out in the form of energetic (14 MeV) neutrons. Fusion power reactors stop these neutrons in a "blanket" where they both heat the blanket and are used to breed tritium (through the reaction n + Li6 -> T + alpha). Breeding tritium is necessary to close the fuel cycle because there are no other sources of tritium available to fuel your DT fusion power reactor. The thermal energy deposited in the blanket is converted to electrical energy through a conventional thermal cycle, which can be expected to have an efficiency of about 35%. It is possible in principle to "directly convert" the remaining 20% of fusion power (which emerges as 3.5 MeV alpha particles). While this technology has yet to be developed, initial exploration suggest that a conversion efficiency as high as 90% may be possible. We will also assume that any recirculated power can be converted back to electrical power through a thermal cycle at a 35% efficiency. With these assumptions you reach break-even (that is, your "power plant" produces exactly as much electrical power as it requires to maintain operation) at a fusion gain -- that is, (fusion power produced)/(recirculated power) -- of 1.41. Of course, the goal of a fusion power plant is to produce excess power which can be sold to pay for the whole enterprise. People will only willingly purchase fusion power if it can be priced competitively with alternate source of electrical power. Electrical generating equipment is expensive (this is the bulk of the capital cost for coal and gas-fired plants, while it is about 1/2 of the capital cost for nuclear plants). A competitive fusion power plant has to be able to sell most of the electrical power which it produces. At a fusion gain of 10 (and the assumptions about power conversion presented above) about 80% of the electrical power generated will be available for sale, while the remaining 20% must be recirculated in order to keep the fusion power plant operating. Nevins [W.M. Nevins, Phys. Plasmas <2> (10), 3804 (October, 1995)] showed that the IEC systems described by Bussard and others cannot achieve a fusion gain greater than 0.1 [disclaimer: I am the Nevins in question]. One concludes that IEC systems cannot form the basis for a commerial electrical power plant. I would further point out that this conclusion is not controversial within the DoE-funded fusion community. Wmnevins 19:26, 5 June 2007 (UTC)
Not sure whether Bussard's devices should go here or in Fusor, though they might get merged anyway. Bussard says a lot, and he says it fast. I'm just an engineer, so I don't know what a lot of these terms mean, but here's my summary of notes from watching the Google lecture. We should cover a lot of this stuff:
Moved to Talk:Polywell#Bussard.27s_polywell_and_lecture
— Omegatron 09:38, 25 November 2006 (UTC)
Have these been peer reviewed? I see no references, and this concerns me. I am not qualified to offer a rebuttal, but it seems to be assuming a relatively simplified situation, ignoring the fact that most fusion in IEC devices occurs in microchannels of low field strength (i.e., in between the wires)[ [2]]. This seems completely against the assumptions of this section.
Can someone please comment on this? -- Rei 17:13, 30 November 2006 (UTC)
References: It would undoubtably be better if we could refer to peer-reviewed publications.
The rule is no original research. When I said "trivial derivations from well-known facts", I was talking about something that is against the rules, but often overlooked and not removed by other editors because of its triviality. As soon as there's a dispute or it's removed by other editors, that obviously no longer applies, and you need to cite references.
I can put "2+2=4" in an article without a reference, and it will probably survive forever. But as soon as someone says it equals 5, it's disputed and I need to add a reference. That's just the nature of the project.
My lack of knowledge or qualification about the subject (which I freely admit) is irrelevant.
And when I say "publish elsewhere", I mean anywhere. Not necessarily a peer-reviewed paper.
This policy does not prohibit editors with specialist knowledge from adding their knowledge to Wikipedia, but it does prohibit them from drawing on their personal knowledge without citing their sources. If an editor has published the results of his or her research in a reliable publication, then s/he may cite that source while writing in the third person and complying with our NPOV policy.
But really, this isn't covered, even in passing, in any peer-reviewed papers?? I'm sure that it is.
Sorry if you're frustrated with us uneducated folk who can't understand your "trivial" derivation (I know basic electromagnetics and vector calc and it's non-trivial to me), but this sort of expert-layman dispute comes up a lot here, and our policies are the tiebreaker, for better or worse. See Wikipedia:Expert retention and Wikipedia:Expert editors, for instance. (I think I added you to the " Users who are content" list a few months ago based on something you had in your user page? I hope that's still accurate, but feel free to put yourself in a different group.) — Omegatron 21:57, 1 December 2006 (UTC)
Moved from article:
{{ Unreferenced}} {{ Original research}} Although portable neutron sources based on the IEC concept are commercially available, most experts are skeptical that the IEC concept can ever be used for power production. Most discussions of IEC consider the behavior of a small number of ions in potential structures imposed by electrodes. A potential well for ions, however, is a potential hill for electrons, so it is not possible to contain a neutral plasma with any set of electrodes. There must be at least some regions where the charge density of one species or the other dominates. As the density in these regions is raised, at some point the net charge density will destroy the potential well.
In pure IEC, the pressure gradient will be balanced by the electric force on the net charge density. In one dimension this is
where p is plasma pressure and ρ is charge density. Gauss's law relates ρ to E as
Together these give
where p0 is a constant of integration, equal to zero if the electric field vanishes when the density does (which minimizes the electric fields and potential drops for a given density). [1] Note the similarity to the concept of magnetic pressure, B²/2μ0, from magnetic confinement fusion. This arises from the symmetry of the Maxwell stress tensor with respect to E and B, with the change of sign being due to the fact that the gradients are parallel to E but perpendicular to B. For comparison, a D-T tokamak reactor would operate at about n = 1020 m−3 and T = 10 keV, which gives an ion pressure of p = (3/2)nkT = 0.24 MPa. Reaching the same pressure in an IEC reactor would require an electric field at the electrode of
If we assume very generously that, say, 1 MV/m could be maintained at the surface of an electrode in a fusion environment, then an IEC reactor would be a factor of 230² worse than a tokamak in terms of both power density and Lawson criterion.
To find the spatial dependence of the pressure outside the electrode we need to relate the pressure to the charge density. The simplest case is to take a single species (ions or electrons) at a uniform temperature, ρ = nq = pq/kT, and to take p0 = 0. The result is p(x) ≈ x−2.
Aside from the achievable electric field strength another factor limiting the density in an IEC device will be the fact that the ions must pass through holes in the electrode, and these holes must be smaller than the Debye length. Otherwise, the potential of the electrode will be dropped in the Debye sheath around the hole and will not be available to confine the ions. If the scale of the holes is δ, then we have
The result has the same form as the previous result, but with the electric field at the electrode replaced by (kT/q)/δ. To achieve 1 MV/m with T = 100 keV would require δ no larger than 10 cm. To achieve confinement comparable to a tokamak would require a value 230 times smaller, namely 0.4 mm. Survival of a material grid in contact with a fusion plasma would be a tremendous problem anyway but is unthinkable if it must be structured on a sub-millimeter scale.
I have reverted a recent edit which removed a statement of Rider's argument and replaced it with a blanket dismissal based on a paper by Rostoker. As far as I can tell, Rostoker is not criticizing the "escape over the top of the electrostatic well" argument, but the "recirculating power with a non-Maxwellian distribution" argument. (Rider was all over the block.) The first is relevant to IEC, the second to Rostoker's CBFR, so this criticism is invalid here. -- Art Carlson 09:03, 7 March 2007 (UTC)
I have reverted these edits. They seem to apply, like the other edit mentioned in this section, to the CBFR, not to any form of IEC. If you disagree, please explain why here. -- Art Carlson ( talk) 09:45, 11 January 2008 (UTC)
The external link in the critique section is not to free content. Is this OK?
"According to Todd Rider in A general critique of inertial-electrostatic confinement fusion systems, net energy production is not viab" 125.238.50.90 22:13, 23 May 2007 (UTC)
"... a small amount of fusion fuel is introduced" -- Could we please link-to or otherwise define what fuel is used in this, as this is an important characteristic of fusion systems. (vs. fission, for example). See for example Nuclear fuel. Thanks. -- 201.19.15.178 15:01, 2 September 2007 (UTC)
Currently, Rider's work is cited inline in the first sentence of the Critique section:
And again under External links:
The second instance is more useful because it is a PDF file, but it lacks the full bibliographical information. I would be inclined to remove the External link, and change the mention in Critique from an external link to a normal reference, including bibliographical info and a link to the PDF. Other suggestions?
On a related note, in the first line of the second paragraph of the Critique section, there is a reference to Nevin in non-standard format.
This is a plea to somebody else to do the work. Even if that doesn't happen, I thought it a good idea to make a note of the potential improvement here for later reference.
-- Art Carlson ( talk) 09:17, 4 February 2009 (UTC)
Hello, I noticed that someone deleted the examples of Amateur fusor work. I very strongly disagree with this. In many ways, the amateurs are ahead of the professionals on this subject. A quick trip to fusor.net shows that a vast, growing and interconnected network of people are building fusors, testing fusors, designing fusors and know more about fusors than the academics. They are making news in the public space and are the most visible manifestation of IEC. They need to be part of this article. — Preceding unsigned comment added by 198.0.90.170 ( talk) 23:07, 6 March 2014 (UTC)
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There are no references to the section that talks about the work on IEC undertaken by The University of Sydney.
We could probably include references such as: https://iec.neep.wisc.edu/usjapan/16th_US-Japan/Wed_AM/Khachan_IEC_2014.pdf
I am sure that with a little effort we could also dig out a bundle of papers... — Preceding unsigned comment added by MrDeconstructo ( talk • contribs) 10:16, 27 January 2022 (UTC)
Hi, I came up with a design for an IEC variant using a pyrolytic graphite inner core. The main problems with IEC as others have discovered is electron density, which can be overcome by using a hybrid confinement method using "stacked" superconducting outer grids similar to Bussards design. It appears that using positrons may be a short term fix as these can be generated using 22Na originating from 25Mg and potentially the reaction could be closed loop if 25Mg is intercalated into the PG. — Preceding unsigned comment added by 185.3.100.7 ( talk) 07:25, 28 March 2019 (UTC)
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The refs of course trace back to you, then from there to Todd Ritter. I am curious about what was wrong, the problem as a whole, or the explaination of why it happened? Or has something happened to fundamentally change his conclusions?
Maury 5 July 2005 21:42 (UTC)
The text I reverted is this:
My objections are
That seemed like enough reasons for a revert. Rider made two points, one that the bremsstrahlung losses for advanced fuels (which are often but not necessarily connected with IEC) are too large for a reasonable energy balance. This is covered under Nuclear_fusion#Bremsstrahlung_losses. The other point (his really creative contribution) is that a non-Maxwellian distribution requires infeasibly large recirculating power. This point is covered, albeit briefly, in Farnsworth-Hirsch_Fusor#Thermalization_of_the_ion_velocities (and is mangled in the articles on Fusion rocket and Cold fusion). We could discuss, if you like, whether other places are more appropriate for this information, or whether it should be expanded or duplicated. Art Carlson 2005 July 6 07:16 (UTC)
Ok, back to you now...
1) I am unaware of any IEC system in which the fuel is not being continually showered into the interior. I suppose if one could create a system with a high enough containment time it might be possible, but I can't even see people suggesting this. Are you being overly piquane here, or do you really feel that a long-containment system is a real possibility, and that in such a system Ritter's concerns will not hold?
2) I am not sure what you mean here. Under the fusor the new ions arriving via acceleration are at a higher energy than the average within the containment area. Fusion products are likewise. As I understand it, generally there is a lot of fairly cool fuel and a small number of much higher temperature fuel. Is this not the case?
3) If (2) is correct the acceleration seen by the typical high-speed particle will be much geater on average. Under an equilibrium system the average particle will generally interact with one of roughly the same energy (given a distribution, of course). Under a non-equilibrium system it will generally interact with one that is much cooler.
4) See (3).
5) Yes
If I have scrambled the two (bremsstrahlung vs recirculation), then considering that the second of his points is still valid for all known IEC approaches, shouldn't that be placed in this article? Even a short note, pointing back to the link you provided would seem appropriate.
As to the other articles, I'm all for removing the content from it entirely. It certainly has nothing to do with fusion rockets, and I can't imagine why anyone would care to read about it in a cold fusion article. In fact, I think I'll go edit them now.
Maury 6 July 2005 12:00 (UTC)
The mention at the end of cold fusion may be out of place, I suppose, but it doesn't seem to read that way. I don't see the mention in fusion rocket any more.
Maury 6 July 2005 12:47 (UTC)
I'm still worried about the realistic limit on the electric field strength at the surface of the electrodes. In the article I assumed the 230 MV/m needed to compare with a tokamak was out of the question and that 1 MV/m was already "generous". But several sources (e.g. [1]) mention a field of 25 GV/m on the tungsten electrode in pyroelectric fusion. Am I being to hard on IEC? On the other hand, we always tried to avoid voltages above 100 V when using Langmuir probes because otherwise we would get arcs. 100 V/mm is only 0.1 MV/m. Art Carlson 12:42, 2005 July 22 (UTC)
80% of the fusion energy produced in a DT cycle comes out in the form of energetic (14 MeV) neutrons. Fusion power reactors stop these neutrons in a "blanket" where they both heat the blanket and are used to breed tritium (through the reaction n + Li6 -> T + alpha). Breeding tritium is necessary to close the fuel cycle because there are no other sources of tritium available to fuel your DT fusion power reactor. The thermal energy deposited in the blanket is converted to electrical energy through a conventional thermal cycle, which can be expected to have an efficiency of about 35%. It is possible in principle to "directly convert" the remaining 20% of fusion power (which emerges as 3.5 MeV alpha particles). While this technology has yet to be developed, initial exploration suggest that a conversion efficiency as high as 90% may be possible. We will also assume that any recirculated power can be converted back to electrical power through a thermal cycle at a 35% efficiency. With these assumptions you reach break-even (that is, your "power plant" produces exactly as much electrical power as it requires to maintain operation) at a fusion gain -- that is, (fusion power produced)/(recirculated power) -- of 1.41. Of course, the goal of a fusion power plant is to produce excess power which can be sold to pay for the whole enterprise. People will only willingly purchase fusion power if it can be priced competitively with alternate source of electrical power. Electrical generating equipment is expensive (this is the bulk of the capital cost for coal and gas-fired plants, while it is about 1/2 of the capital cost for nuclear plants). A competitive fusion power plant has to be able to sell most of the electrical power which it produces. At a fusion gain of 10 (and the assumptions about power conversion presented above) about 80% of the electrical power generated will be available for sale, while the remaining 20% must be recirculated in order to keep the fusion power plant operating. Nevins [W.M. Nevins, Phys. Plasmas <2> (10), 3804 (October, 1995)] showed that the IEC systems described by Bussard and others cannot achieve a fusion gain greater than 0.1 [disclaimer: I am the Nevins in question]. One concludes that IEC systems cannot form the basis for a commerial electrical power plant. I would further point out that this conclusion is not controversial within the DoE-funded fusion community. Wmnevins 19:26, 5 June 2007 (UTC)
Not sure whether Bussard's devices should go here or in Fusor, though they might get merged anyway. Bussard says a lot, and he says it fast. I'm just an engineer, so I don't know what a lot of these terms mean, but here's my summary of notes from watching the Google lecture. We should cover a lot of this stuff:
Moved to Talk:Polywell#Bussard.27s_polywell_and_lecture
— Omegatron 09:38, 25 November 2006 (UTC)
Have these been peer reviewed? I see no references, and this concerns me. I am not qualified to offer a rebuttal, but it seems to be assuming a relatively simplified situation, ignoring the fact that most fusion in IEC devices occurs in microchannels of low field strength (i.e., in between the wires)[ [2]]. This seems completely against the assumptions of this section.
Can someone please comment on this? -- Rei 17:13, 30 November 2006 (UTC)
References: It would undoubtably be better if we could refer to peer-reviewed publications.
The rule is no original research. When I said "trivial derivations from well-known facts", I was talking about something that is against the rules, but often overlooked and not removed by other editors because of its triviality. As soon as there's a dispute or it's removed by other editors, that obviously no longer applies, and you need to cite references.
I can put "2+2=4" in an article without a reference, and it will probably survive forever. But as soon as someone says it equals 5, it's disputed and I need to add a reference. That's just the nature of the project.
My lack of knowledge or qualification about the subject (which I freely admit) is irrelevant.
And when I say "publish elsewhere", I mean anywhere. Not necessarily a peer-reviewed paper.
This policy does not prohibit editors with specialist knowledge from adding their knowledge to Wikipedia, but it does prohibit them from drawing on their personal knowledge without citing their sources. If an editor has published the results of his or her research in a reliable publication, then s/he may cite that source while writing in the third person and complying with our NPOV policy.
But really, this isn't covered, even in passing, in any peer-reviewed papers?? I'm sure that it is.
Sorry if you're frustrated with us uneducated folk who can't understand your "trivial" derivation (I know basic electromagnetics and vector calc and it's non-trivial to me), but this sort of expert-layman dispute comes up a lot here, and our policies are the tiebreaker, for better or worse. See Wikipedia:Expert retention and Wikipedia:Expert editors, for instance. (I think I added you to the " Users who are content" list a few months ago based on something you had in your user page? I hope that's still accurate, but feel free to put yourself in a different group.) — Omegatron 21:57, 1 December 2006 (UTC)
Moved from article:
{{ Unreferenced}} {{ Original research}} Although portable neutron sources based on the IEC concept are commercially available, most experts are skeptical that the IEC concept can ever be used for power production. Most discussions of IEC consider the behavior of a small number of ions in potential structures imposed by electrodes. A potential well for ions, however, is a potential hill for electrons, so it is not possible to contain a neutral plasma with any set of electrodes. There must be at least some regions where the charge density of one species or the other dominates. As the density in these regions is raised, at some point the net charge density will destroy the potential well.
In pure IEC, the pressure gradient will be balanced by the electric force on the net charge density. In one dimension this is
where p is plasma pressure and ρ is charge density. Gauss's law relates ρ to E as
Together these give
where p0 is a constant of integration, equal to zero if the electric field vanishes when the density does (which minimizes the electric fields and potential drops for a given density). [1] Note the similarity to the concept of magnetic pressure, B²/2μ0, from magnetic confinement fusion. This arises from the symmetry of the Maxwell stress tensor with respect to E and B, with the change of sign being due to the fact that the gradients are parallel to E but perpendicular to B. For comparison, a D-T tokamak reactor would operate at about n = 1020 m−3 and T = 10 keV, which gives an ion pressure of p = (3/2)nkT = 0.24 MPa. Reaching the same pressure in an IEC reactor would require an electric field at the electrode of
If we assume very generously that, say, 1 MV/m could be maintained at the surface of an electrode in a fusion environment, then an IEC reactor would be a factor of 230² worse than a tokamak in terms of both power density and Lawson criterion.
To find the spatial dependence of the pressure outside the electrode we need to relate the pressure to the charge density. The simplest case is to take a single species (ions or electrons) at a uniform temperature, ρ = nq = pq/kT, and to take p0 = 0. The result is p(x) ≈ x−2.
Aside from the achievable electric field strength another factor limiting the density in an IEC device will be the fact that the ions must pass through holes in the electrode, and these holes must be smaller than the Debye length. Otherwise, the potential of the electrode will be dropped in the Debye sheath around the hole and will not be available to confine the ions. If the scale of the holes is δ, then we have
The result has the same form as the previous result, but with the electric field at the electrode replaced by (kT/q)/δ. To achieve 1 MV/m with T = 100 keV would require δ no larger than 10 cm. To achieve confinement comparable to a tokamak would require a value 230 times smaller, namely 0.4 mm. Survival of a material grid in contact with a fusion plasma would be a tremendous problem anyway but is unthinkable if it must be structured on a sub-millimeter scale.
I have reverted a recent edit which removed a statement of Rider's argument and replaced it with a blanket dismissal based on a paper by Rostoker. As far as I can tell, Rostoker is not criticizing the "escape over the top of the electrostatic well" argument, but the "recirculating power with a non-Maxwellian distribution" argument. (Rider was all over the block.) The first is relevant to IEC, the second to Rostoker's CBFR, so this criticism is invalid here. -- Art Carlson 09:03, 7 March 2007 (UTC)
I have reverted these edits. They seem to apply, like the other edit mentioned in this section, to the CBFR, not to any form of IEC. If you disagree, please explain why here. -- Art Carlson ( talk) 09:45, 11 January 2008 (UTC)
The external link in the critique section is not to free content. Is this OK?
"According to Todd Rider in A general critique of inertial-electrostatic confinement fusion systems, net energy production is not viab" 125.238.50.90 22:13, 23 May 2007 (UTC)
"... a small amount of fusion fuel is introduced" -- Could we please link-to or otherwise define what fuel is used in this, as this is an important characteristic of fusion systems. (vs. fission, for example). See for example Nuclear fuel. Thanks. -- 201.19.15.178 15:01, 2 September 2007 (UTC)
Currently, Rider's work is cited inline in the first sentence of the Critique section:
And again under External links:
The second instance is more useful because it is a PDF file, but it lacks the full bibliographical information. I would be inclined to remove the External link, and change the mention in Critique from an external link to a normal reference, including bibliographical info and a link to the PDF. Other suggestions?
On a related note, in the first line of the second paragraph of the Critique section, there is a reference to Nevin in non-standard format.
This is a plea to somebody else to do the work. Even if that doesn't happen, I thought it a good idea to make a note of the potential improvement here for later reference.
-- Art Carlson ( talk) 09:17, 4 February 2009 (UTC)
Hello, I noticed that someone deleted the examples of Amateur fusor work. I very strongly disagree with this. In many ways, the amateurs are ahead of the professionals on this subject. A quick trip to fusor.net shows that a vast, growing and interconnected network of people are building fusors, testing fusors, designing fusors and know more about fusors than the academics. They are making news in the public space and are the most visible manifestation of IEC. They need to be part of this article. — Preceding unsigned comment added by 198.0.90.170 ( talk) 23:07, 6 March 2014 (UTC)
Hello fellow Wikipedians,
I have just modified one external link on Inertial electrostatic confinement. Please take a moment to review my edit. If you have any questions, or need the bot to ignore the links, or the page altogether, please visit this simple FaQ for additional information. I made the following changes:
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Cheers.— InternetArchiveBot ( Report bug) 11:26, 22 January 2018 (UTC)
There are no references to the section that talks about the work on IEC undertaken by The University of Sydney.
We could probably include references such as: https://iec.neep.wisc.edu/usjapan/16th_US-Japan/Wed_AM/Khachan_IEC_2014.pdf
I am sure that with a little effort we could also dig out a bundle of papers... — Preceding unsigned comment added by MrDeconstructo ( talk • contribs) 10:16, 27 January 2022 (UTC)
Hi, I came up with a design for an IEC variant using a pyrolytic graphite inner core. The main problems with IEC as others have discovered is electron density, which can be overcome by using a hybrid confinement method using "stacked" superconducting outer grids similar to Bussards design. It appears that using positrons may be a short term fix as these can be generated using 22Na originating from 25Mg and potentially the reaction could be closed loop if 25Mg is intercalated into the PG. — Preceding unsigned comment added by 185.3.100.7 ( talk) 07:25, 28 March 2019 (UTC)