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A great deal of work has been done in an attempt to harness this reaction.
It appears that no one has solved the many serious technical issues that are involved.
This new topic is available for any NewMars member to contribute links or text to help members learn about the process, or to keep up with developments.
The opening post will offer a link to a ChatGPT transcript which covers the differences between Boron-10 and Boron-11.
Each yields useful results when bombarded with protons of the correct energy level, but the results differ significantly.
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This post is reserved for an index to posts that may be contributed by NewMars members:
Index:
Post #7: HG Muller - review of the problem to be solved
https://newmars.com/forums/viewtopic.ph … 94#p242494
Post #8: HG Muller on energy levels and enrichment of Boron-11 vs Boron-10
https://newmars.com/forums/viewtopic.ph … 95#p242495
Post #9: HG Muller on "barn" as a measure of cross section in nuclear reactions
https://newmars.com/forums/viewtopic.ph … 98#p242498
Post #10: HG Muller on 3He+D compared with D+T (3He+D (-> 4He+p))
https://newmars.com/forums/viewtopic.ph … 98#p242498
Post #11 Calliban - high charge density of boron nucleus
https://newmars.com/forums/viewtopic.ph … 21#p242521
Post #12 Calliban Energy to fully ionize boron (includes link to nist site)
https://newmars.com/forums/viewtopic.ph … 22#p242522
Below is the original contents of this post:
The transcript at the link below covers some differences between Boron-10 and Boron-11.
The methods of separation of the isotopes is covered.
Production of alpha particles by Boron-11 >> Carbon 12 is covered
Generation of a positron Boron-10 >> Carbon-11 is covered.
https://docs.google.com/document/d/1pka … sp=sharing
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In another topic, the relationship between Quantum effects and biological systems is considered.
The author is: Clarice D. Aiello, University of California, Los Angeles
One of the aspects of Quantum Physics mentioned in the article is spin of particles such as electrons, but apparently including all (or most) known particles, and (presumably) unknown ones as well.
I bring this up in the context of the outstanding and (so far) unsolved problem of achieving reliable, efficient fusion of Boron-11 with Protons. The problem facing all researchers is that the protons gathered in the nucleus of Boron-11 (or any nucleus) don't appreciate the arrival of another proton. It is possible to persuade the reluctant members of the Boron-11 "family" to accept an intruder, but the party breaks up shortly afterward.
I am interested in spin as a possible angle of approach to improving the effectiveness and efficiency of persuading these reluctant parties to join together for a good cause. The good cause (of course) is space craft propulsion of thermal or electrical energy for human applications.
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In pursuing the question of how to create Tritium for a potential nuclear battery market, I found it useful to investigate Boron-11+Proton reactions. It's been a while since I looked into progress in this area.
ChatGPT4 suggested a Google service: scholar.google.com
I entered a search string looking for the energy of a Proton that successfully enters a Boron-11 nucleus.
There were many citations delivered by the search request. The first of this was for this paper:
Home Journal of Fusion Energy
Article
HB11—Understanding Hydrogen-Boron Fusion as a New Clean Energy Source
Review
Open access
Published: 13 May 2023Volume 42, article number 17, (2023)
Cite this article
This is a thorough discussion of the work done by numerous researchers of a number of years, starting in 1930 when Boron-11+Proton was first discovered. The paper discusses Deuterium-Tritium fusion efforts at considerable length, and provides a long list of advantages of B11-P if it can be made to work.
It appears that break-even has not been achieved by any of the research teams. Two approaches may be of interest to NewMars readers. One is the traditional "Pitcher-Catcher" approach. The second is the newer "In-Target" approach, which features energy delivered by a laser to a target that is enriched with Hydrogen. The theory of operation is to cause the Hydrogen to move at just the right velocity to enter the B11 nucleus.
The paper is available as a downloadable pdf.
The specific item I was looking for was the energy of the Proton that enters the B11 nucleus ... that showed up as a data point in a range of uncertainty:
Material Properties One basic element which is still not precisely known, despite the discovery of HB11 fusion almost 90 years ago, is the precise behavior of proton boron fusion cross-section. Classical data on the proton-boron cross section by Nevins & Swain [4] has been more recently revisited by Sikora and Weller [45] who found higher cross sections in the range of "10 MeV". Still, the exact shape of the cross section at energies below a few hundred "keV" and for energies " > 3MeV"is not known. Presently, several experiments are being planned to fill these gaps the results of which will be critical to developing the models used to simulate laser-driven proton-boron fusion experiments. Similarly, an understanding of the equation of state and opacities of boron under extreme conditions will be another critical requirement for accurate simulations, particularly under compression as proposed for the "Hybrid Burn”.
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The article at the link below reports on progress by one of many groups trying to achieve fusion with Boron 11 and hydrogen:
https://www.yahoo.com/news/scientists-a … 51256.html
I'll try to capture the text for NewMars ...
The Cool Down
Scientists achieve breakthrough solution to decades-long issue with virtually limitless energy device: 'Charting a path'
Ren VenkateshWed, May 14, 2025 at 7:15 AM EDT
3 min readScientists achieve breakthrough solution to decades-long issue with virtually limitless energy device: 'Charting a path'
Generate Key TakeawaysWhile nuclear fusion technology would prove a promising energy source with zero carbon pollution and minimal radioactive waste if successfully commercialized, scientists are still struggling to navigate its financial and technical roadblocks.
On that front, researchers at California's TAE Technologies have made significant strides in reducing the cost and complexity of fusion technology without compromising on its extraordinary efficiency.
Ordinarily, fusion requires engineers to generate plasma at extremely high temperatures and to confine the energy released, often with Field-Reversed Configuration technology, TAE explained in a release.
The FRC tech produces its own internal magnetic field to yield up to 100 times more energy than a typical tokamak reactor and makes hydrogen-boron fuel — "the cleanest, safest, and most sustainable option for the planet," noted the release — more viable.
Unfortunately, plasma formation using the FRC has so far proven both costly and unstable.
TAE Technologies' solution, published in the journal Nature Communications, involves injecting neutral particle beams into the company's new advanced particle accelerator "Norm" to heat and stabilize an FRC plasma.
The engineers' findings have the potential to "[reduce] the machine's size, complexity and cost by up to 50% and [optimize] for economic competitiveness and commercial viability," the release continued.
As demands for global energy production continue to rise under our growing populations and industrial developments, moving away from dirty energy becomes increasingly important to avert environmental catastrophe.
Burning fuels like coal and oil releases carbon pollution into our atmosphere — 36.8 billion tonnes in 2023, and still rising, according to NASA's Earth Observatory — and traps heat on our planet. The ripple effects of rising temperatures include more intense extreme weather events and threats to our food and crop supply.
Fusion technology supplies massive amounts of power without any reliance on fuel-burning, and without the radioactive waste problem that afflicts today's fission-based technology.
Commercializing fusion technology may not only limit the climate impact of energy generation, but it could also slash utility costs for the average individual by enabling power companies to more easily and efficiently keep up with demand.
TAE's "Norm" development, for instance, may "[chart] a path for streamlined devices that directly addresses the commercially critical metrics of cost, efficiency, and reliability," theorized Michl Binderbauer, CEO of TAE Technologies.
"This milestone significantly accelerates TAE's path to commercial hydrogen-boron fusion that will deliver a safe, clean, and virtually limitless energy source for generations to come," Binderbauer added.
"Norm" is set to precede TAE's next reactor prototype, "Copernicus," which TAE engineers anticipate will demonstrate fusion as a viable energy source before 2030.
As TAE continues to research and refine its technology, TAE's first full-fledged nuclear fusion power plant, known as "Da Vinci," will hopefully come online in the early 2030s.
Join our free newsletter for weekly updates on the latest innovations improving our lives and shaping our future, and don't miss this cool list of easy ways to help yourself while helping the planet.
If someone in the active membership understands this report, and can explain it in a few words, please do so. I think that Boron 11 Hydrogen fusion is one of the most attractive pathways available, but it appears to be as elusive as deuterium-tritium fusion. I am ready for ** someone ** to succeed in this quest!
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For HG Muller,
This topic is available for development.
It can include history, links to resources, explanations of key concepts, questions from NewMars members and replies to those questions. My interest is in seeing this particular fusion method realized in practice.
All the failures to get there need to be carefully documented along the way.
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Note that I am not a nuclear physicist; I streamed into a PhD in atomic physics (which deals with the electronic structure of atoms, assuming the nucleus is just a structureless point charge) from a formal chemistry education with specialty 'physical chemistry'. (Which did not even have a nuclear physics course in its curriculum.) So what I am going to write now is entirely based on general physics knowledge.
It is important to keep in mind that nuclear reactions caused by accelerating a beam of protons (or nuclei of other stable isotopes) into a stationary target with the density of a solid is a great way to measure which nuclear reactions are possible, and how their probability depends on energy. This because a trillion protons is still only 1.6 picogram of matter. So accelerating that to particle energies of billions of electron volt doesn't take much energy. And even if only one in a billion collisions produces a fusion, you would see 1000 fusions from that, and already are able to get meaningful statistics on the results.
But for producing energy it is useless. Almost all collisions between an accelerated particle and a nucleaus in the stationary target will miss the nucleus so much that it only leads to elastic scattering: the particle trajectory bends in a random direction, and cedes part of its energy to the nucleus. This repeats until the particle has lost virtually all its energy, without a significant chance it fused in the mean time.
So a significant fraction of fusion events can only be achieved if the rapid loss of energy can be prevented, by giving all particles similar energies, so they gain from a collision as often as they lose it. In other words, if you mix them at high temperature. And to give them energies where they can fuse, that is an insanely high temperature. For Boron the nuclear electrostatic repulsion to a proton is 5 times stronger than between hydrogen isotopes, so it would need a much higher temperature as witt D+T fusion.
At some collision energies the probability to fuse can be orders of magnitude larger than at most others. This is known as a resonance. It is a general quantum-mechanic effect. It occurs when there is some kinetic barrier that makes it very difficult for particles bound to each other to fall apart, even when they contain enough energy to in principle do so. This can be a pure quantum-mechanical effect, an energy barrier sticking out above the energy of the system, through which a particle has to tunnel to get away. But it can also be due to dynamics, if the energy that a single particle would need to escape is present in the bound system divided over many particles. So that it needs a very special sequence of (internal) collisions to concentrate all energy into one.
The longer the average lifetime of such a resonance is, the larger the enhancement of the reverse 'capture' process, but the more precise the energy of the colliding particle has to be to experience that enhancement. Ion beams can be tuned very precisely to such an energy, but the first collision will still have a very low peobability for fusion even on the resonance. And if the fusion doesn't take place on the first collision, the particle is scattered with a lower energy (due to the recoil of its target), and the advantage is gone. In a hot thermal mixture energies are never sharply defined, and the contribution of resonances to the fusion probability will be small.
Boron-11 + proton is an unbound version of carbon-12, and there should exist tables that list which excited states the 12C nuclide has, and this probably would extend to the low-lying resonances as well. (In a sense all nuclear excited states are resonances, because they can 'dissociate' into a photon (usually gamma ray) and a lower-lying state of the same nucleus.)
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You asked about the collison energy. It appears the resonance you are after, which makes the unstable 12C intermediate decay into 3 alpha particles, is the famous Hoyle resonance. (Of importance because in stars the inverse process of this decay synthesizes C out of He after hydrogen is used up.) The wikipedia page on Carbon-12 says this lies 7654.2 keV above the 12C ground state.
So you would just have to convert the difference between the 12C mass and the total mass of 11B plus a 1H (doesn't matter if these masses are of the neutral atoms or nuclei, as they contain equal electrons), and convert that to eV using E = mc2. That tells you where the energy of 12C is compared to the rest energy of 11B+p. You then have to 'aim' 7.6 MeV higher.
Note that enriching Boron for 11B should be a piece of cake. Just (ultra-)centrifuge diborane (B2H6). This is a gas at room temperature. You start with 64% of the sought stuff (molecular mass 2*11+6 = 28), and the mass difference with the stuff you don't want is 3.5% and 7%. That makes it much easier than enriching uranium: UF6 has mass 349 or 352, a difference of less than 1%. So you should get much higher enrichment factor per centrifuge.
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'Barn' is just a non-SI unit for area, popular amongst nuclear physicists. It is common to express a reaction rate of colliding particles for getting some particular end product as a 'cross section'. This uses the classical metaphore of the target being a hard sphere, which a beam of point particles (the intensity of which can be expressed as a certain number of particles per second per area) either hits or misses. Every hit then results in the sought reaction, every miss in something else (which may be nothing at all).
Intuitively you would expect the total cross section for any nuclear reaction happening to be something on the order of the size of the nucleus,perhaps augmented by the range of the strong nuclear force. This is in the range of a few femtometer squared (so 1e-30 m2). I looked up that 1 barn = 1e-28m2. At resonances the cross section can be far larger than the nuclear size, which defies intuition. It is as if the nucleus would be able to 'reel in' particles that pass it at a distance of many times its size.
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The problem of getting 11B+p fusion is similar to that for D+T fusion. I have seen proposals for another aneutonic fusion, through 3He+D (-> 4He+p), a so-called 'advanced fuel'. This requires higher temperature, but has the advantage that a much larger fraction of the liberated energy remains trapped in the plasma (if magnetic confinement is used). The neutron from the D+T reaction is 4 times larger than the He, and thus gets 80% of the energy (4 times the velocity, by momentum conservation). Because it is neutral it does not feel the magnetoc field, and leaves the plasma. Which then has to sustain its high temperature only through the 20% in the He. With 3He+D all energy goes into the plasma, so 5 times as much.
Disadvantage of course is that 3He is extremely rare. 11B does not suffer from that, but requires still higher temperature (and probably less energy release per fusion event).
Alternative for magnetic confinement is inertial confinement, basically microscopic hydrogen bombs ignited by a laser pulse or heavy-ion beam. The laser or ion beam basically serve to compress the target, not so much heat it (which will happen by the compression anyway). Laser pulses are mroe effective, but generating laser light is a very inergy-inefficient process in itself. I don't know how hard it would be to run 11B+p vs D+T in initial-confinement fusion.
Neither of these schemes is currently working well enough even for the supposedly easiest D+T case.
Last edited by HG Muller (2026-10-29 13:39:47)
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The problem with Boron-Proton fusion generally is the high charge density of the boron nucleus. This leads to bremsstrahlung emissions which drain energy from the system. This will be a problem regardless of whether MCF or ICF is used. The 3He-De reaction may suffer less in this respect. However, this fusion reaction is not aneutronic, because a portion of De nuclei will reacte with each other. Some 50% of those reactions will release neutrons. Not that that is necessarily a problem. The neutrons yielded by fusion reactions may have uses of their own. But the hard neutron spectrum from De-T fusion will have life limiting effects of reaction chamber lining, because they have enough energy to displace atoms from metallic lattices.
Last edited by Calliban (2026-10-30 14:09:46)
"Plan and prepare for every possibility, and you will never act. It is nobler to have courage as we stumble into half the things we fear than to analyse every possible obstacle and begin nothing. Great things are achieved by embracing great dangers."
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One problem with using boron in ICF: To completely ionise boron requires an energy of 671eV.
https://physics.nist.gov/cgi-bin/ASD/ie … &biblio=on
That is quite a lot of energy and it may make it difficult to achieve the same sort of number density achievable in hydrogen based fusion. It means we need to input that much energy into the boron before we can convert it into a compressible plasma. That is quite a challenging requirement.
For hydrogen, we need only 13.6eV.
https://physics.nist.gov/cgi-bin/ASD/ie … &biblio=on
This means that essentially, the entire De-T pellet will be plasma following compression. In fact, average particle energy is closer to 300eV at the end of ablation.
I have often wondered if we could trigger ICF by putting a micrometer sized sphere of enriched uranium at the heart of a fuel pellet. After compression at 300eV, a portion of the hot hydrogen ions at the higher end of the boltzman tail will have enough energy to fusion. This would shower a small uranium core with neutrons causing fission. Being just a few micrometers in diameter, most fission products would escape the core with most of their energy - an average of 80MeV each. These would have a range of <0.1micrometer in the surrounding compressed fuel and would heat the compressed hydrogen around the core to high energies. This would result in more fusion events, releasing more neutrons into the core and causing more fission. The result is a feedback effect, that rapidly heats the hydrogen in the centre of the pellet to temperature of several KeV. As hot hydrogen ions stream away from the core, they create fusion in the surrounding compressed fuel. The result is a detonation wave that rapidly fuses the whole pellet. In this way, the uranium core acts as a spark plug. It would contribute little to total energy production but it provides a highly localised heat source at the heart of the pellet at the precise moment that maximum fuel density is reached.
Both fission and fusion releases abundant neutrons. These neutrons may be especially useful in ICF. If we can 6Li-De pellets, with uranium cores, the neutrons released by fusion and fission will convert 6Li into tritium, which will then fuse with deuterium to release even more neutrons. The benefit here is LiD is denser and easier to store in fuel tanks at room temperature. The disadvantage is that a lithium based fuel cannot be compressed to the same density as a De or De-T fuel. Maybe the uranium core will provide sufficient heating to reduce the compression requirement.
Last edited by Calliban (2026-10-30 14:53:00)
"Plan and prepare for every possibility, and you will never act. It is nobler to have courage as we stumble into half the things we fear than to analyse every possible obstacle and begin nothing. Great things are achieved by embracing great dangers."
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We have two qualified contributors engaged with this topic.
RobertDyck is particularly adept at collecting and showing the big picture.
I would like to see a concise summary of the successful fusion of a Proton with a Boron-11 atom.
We understand that Nature has provided formidable defenses against penetration of the Boron nucleus.
However, we know that on rare occasions, such penetration is possible.
We also know that (to the best of my knowledge) simple heating of a cluster of Boron atoms is not a successful strategy.
If it were, the many attempts along that line would have succeeded.
This topic is available for detailed exposition of every failure we can find.
Out of study of all those failures, someone in the NewMars forum may see an opportunity.
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The conversation with Gemini took place some time ago. I found it today while searching for something else. It explains the term "barn" and related concepts pertinent to this topic.
My interest in pursuing this topic is primarily the collection of relevant knowledge, and secondarily inspiration of our members to contribute with insights or questions that might lead toward success. At present (to the best of my understanding) we humans have probed at the problem and defined how difficult it will be to solve, but no one has identified a procedure that would unlock the stored energy that is available.
BARN discussion - Hi Gemini! Thank you for your assistance with numerous requests in different accounts! Today I am hoping to enlist your support for an inquiry into the meaning of the term Barn, used for evaluation of materials in the context of atomic physics. I understand the term was coined as scientists attempted to understand the physics of particle interaction with nuclei in the pursuit of fission. I am under the impression the term was initially applied with neutrons in mind. My question is: is there a similar concept for protons? I am interested in knowing the susceptibility of nuclei to protons, bearing in mind that protons must contend with the electric force as well as the atomic force.
***
You're absolutely right on all counts, Gemini! The "barn" is a fascinating and somewhat whimsical unit in atomic and nuclear physics, directly tied to the early efforts to understand nuclear reactions, especially neutron-induced fission.The "Barn" Explained
Origin: The term "barn" (symbol: b) was indeed coined during the Manhattan Project in 1942 by American physicists Marshall Holloway and Charles P. Baker at Purdue University. They were measuring the cross-sections of nuclear reactions and found that the effective target area of a uranium nucleus for neutrons was surprisingly large, so large it was described as being "as big as a barn" or "like hitting the broad side of a barn." This was then formally adopted as a unit.Definition: One barn is equal to 10 −28 m 2 or 10 −24 cm 2 .
This is a very small area, but in the context of subatomic particles, it's considered quite "large" for an interaction probability.
Meaning: Cross-Section: In physics, a "cross-section" (often denoted by σ) is not a physical area of the nucleus in the classical sense, but rather a measure of the probability of a specific interaction occurring between an incident particle (like a neutron or proton) and a target nucleus. A larger cross-section means a higher probability of that particular interaction. Different types of interactions (scattering, absorption, fission, etc.) will have different cross-sections for the same particle-nucleus pair.
Is there a similar concept for protons?
Yes, absolutely! The concept of a "cross-section" measured in barns (or its submultiples like millibarns, microbarns, nanobarns, picobarns, femtobarns, etc.) is fundamental to all particle interactions, not just those involving neutrons.For protons interacting with nuclei, scientists routinely measure and calculate proton-nucleus cross-sections. These cross-sections tell us the likelihood of various outcomes when a proton collides with a nucleus, such as:
Elastic scattering: The proton bounces off the nucleus without changing its internal state or that of the nucleus.
Inelastic scattering: The proton excites the nucleus to a higher energy state, or itself changes its internal state, losing some energy in the process.
Nuclear reactions: The proton is absorbed by the nucleus, leading to a new nucleus and/or the emission of other particles (e.g.,
(p,n) for proton-in, neutron-out;
(p,α) for proton-in, alpha-particle-out; etc.).Spallation/Fragmentation: At higher energies, the proton can essentially shatter the nucleus into smaller fragments.
Protons vs. Neutrons and the Electric Force
You're right to point out that protons must contend with the electric (Coulomb) force, unlike neutrons. This is a crucial difference:Coulomb Repulsion: Protons are positively charged, and nuclei are also positively charged. This means there's a repulsive electrostatic force between an incident proton and the target nucleus. For the proton to interact via the strong nuclear force (which is responsible for most nuclear reactions), it must overcome this Coulomb barrier. This typically requires higher kinetic energies for the incident protons compared to neutrons, especially for heavier nuclei with larger positive charges.
Energy Dependence: The cross-sections for proton-induced reactions are strongly dependent on the incident proton's energy. At low energies, the Coulomb repulsion significantly reduces the probability of a proton reaching the nucleus, leading to very small cross-sections. As the proton's energy increases, it can more easily overcome the barrier, and the cross-sections for various nuclear reactions rise.
Tunneling: Even at energies below the classical Coulomb barrier, there's a quantum mechanical probability for the proton to "tunnel" through the barrier and interact with the nucleus. However, this probability decreases rapidly as the energy drops further below the barrier.
Despite these differences, the "barn" as a unit for cross-section remains the standard for describing proton-nucleus interactions, just as it is for neutron-nucleus interactions, electron scattering, and even interactions in high-energy particle accelerators (like proton-proton collisions at the LHC). The specific cross-section values will, of course, vary greatly depending on the type of particle, its energy, and the target nucleus.
So, while neutrons might have seemed like "easier targets" for early fission experiments due to the absence of the Coulomb barrier, the underlying concept of a "cross-section" measured in barns is universally applied to quantify the susceptibility of nuclei to all types of interacting particles, including protons.
In re-reading the conversation above, I realized I had missed the concept "Big as a Barn Door" as meaning something unexpectedly large. While the origin of the term relates to Uranium fission by a neutron, in the context of ** this ** topic I would expect the "barn" value for Boron-11 to be less than that for uranium. If a member were willing to take a moment to create a post, please show the relative "barn" values for Uranium vs Boron-11, and add such related information as seems needed.
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The idea of using uranium in ICF pellets might not survive quantitative considerations. There is a reason the critical mass of uranium is in the kg range, and not micrograms; this is because the mean free path of neutrons in uranium is so large that smaller samples would let most neutrons escape before they could trigger a fission. And there is also an energy issue: fission of U235 is most efficiently triggered by thermal neutrons. This is why nucear reactors need 'moderators': light elements where the energetic neutrons released in fission events lose most of their energy through collisions before they return to the uranium. This slowdown cannot take place in the presence of U238, which would efficiently capture neutrons in the intermediate energy range (to eventually form plutonium).
Neutrons released in fusion are very energetic (at least for D+T). They can smash the otherwise not fisioning U238, but I think the cross section is pretty small (and the mean free path of such neutrons through U238 rather long).
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The idea of using uranium in ICF pellets might not survive quantitative considerations. There is a reason the critical mass of uranium is in the kg range, and not micrograms; this is because the mean free path of neutrons in uranium is so large that smaller samples would let most neutrons escape before they could trigger a fission. And there is also an energy issue: fission of U235 is most efficiently triggered by thermal neutrons. This is why nucear reactors need 'moderators': light elements where the energetic neutrons released in fission events lose most of their energy through collisions before they return to the uranium. This slowdown cannot take place in the presence of U238, which would efficiently capture neutrons in the intermediate energy range (to eventually form plutonium).
Neutrons released in fusion are very energetic (at least for D+T). They can smash the otherwise not fisioning U238, but I think the cross section is pretty small (and the mean free path of such neutrons through U238 rather long).
You may be right. The mean free path of fission neutrons in uranium-235 metal is approximately 16.5 cm. That is at normal density, but given how dense the electron shell of uranium is, it won't compress to anywhere near the same extent as the LiD that surrounds it. So only about 1 in 165,000 fission energy neutrons entering a 1 micrometre 235U sphere would cause fission. Fission fragment KE amounts to ~160MeV. That is sufficient to heat 4000 particles to 40KeV. Even with a very dense LiD reflector around the sphere, there is unlikely to be sufficient neutronic feedback from reflection and fusion in surrounding material, for fission to be self-sustaining. We would likely need to hit the 235U with a lot of external neutrons. But the compressed LiD shell would scatter a portion of them before they reach the core and many would miss the core entirely if they enter the pellet at the wrong angle.
The question is, can we economically (in terms of energy) bombard the core with enough neutrons to heat the fuel around it to ignition? What would ignition look like in terms of plasma energy and volume? How many neutrons would it take and how could they feasibly be generated?
Last edited by Calliban (Today 09:02:10)
"Plan and prepare for every possibility, and you will never act. It is nobler to have courage as we stumble into half the things we fear than to analyse every possible obstacle and begin nothing. Great things are achieved by embracing great dangers."
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