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As I understand it, the usual configuration of a tritium boosted weapon is that deuterium (D) and tritium (T) are placed in the centre of the pit (ie the core of plutonium or highly enriched unranium) of an implosion-type weapon. The shockwave of the implosion passes into the pit and produces a very high temperature in the centre sufficient to ignite thermonuclear fusion in the DT mix. The fusion reactions give off a burst of neutrons which initiate the fission chain reaction more quickly than would spontaneous fission alone. This increases the amount of fission that can occur in the brief time before the pit blows itself apart. The thermonuclear yield is insignificant, but the yield of the fission reaction is greatly increased. Man with two legs 14:12, 11 October 2005 (UTC)
I believe it takes not just the implosion energy from conventional explosives, but fission energy from the early stages of the fission chain reaction, to start fusion. After this, both fission and fusion proceed, the fission assisting the fusion by continuing heating and compression, and the fusion assisting the fission by radiating fast neutrons. As the fission fuel depletes and also explodes outward, it falls below the density needed to stay critical by itself, but the fusion neutrons keep fission going for longer than it would otherwise.
Besides increased yield (for the same amount of fission fuel with vs. without boosting) and the possibility of variable yield (by varying the amount of fusion fuel), possibly even more important advantages are allowing the weapon (or primary of a weapon) to have a smaller amount of fission fuel (reducing the risk of predetonation) and more relaxed requirements for implosion.
Also, I believe all boosting of primaries is done with gas, not 6LiD, probably because the latter is not a net producer of neutrons, and would not provide the quick neutron boost that DT fusion does. -- JWB ( talk) 07:19, 22 November 2007 (UTC)
The Nuclear Weapons Archive you gave discusses fusion via chemical explosive implosion farther down the page and says it's not practical.
The external neutron generator is the initiator.
“ | A somewhat similar approach is to use the implosion to initiate a neutron generating fusion reactions with tritium and deuterium (described in Section 2.2 below). It may seem surprising that this can be made to work, given the well known fact that fission explosions are required to produce the temperatures that fusion reactions normally need. Three considerations overcome this obstacle. First, an exceedingly low rate of fusion is actually required. One neutron (and thus one fusion) every 10 nanoseconds is sufficient, a rate that is only some 10^-24 as fast as an actual fusion explosion would need. Second, implosions focus energy and can reach very high temperatures near the center. Theoretically the temperature at the center is infinitely high, but lack of perfect symmetry reduces this. Even so, a high precision implosion can reach temperatures of several hundred thousand degrees C. Third, the velocity of atoms in a gas or plasma is a statistical (Maxwellian) distribution. A very small portion of the atoms can greatly exceed the average energy. Thus enough atoms in the D-T mixture near the center can reach fusion energies to produce the required rate of neutron production. This type of implosion initiator is even more difficult to engineer than the Be/Po-210 type since the very high precision implosion is required to achieve the required symmetry. The major advantage is that the short half-life Po-210 is not needed. | ” |
T-T fusion is listed at Nuclear fusion#Criteria and candidates for terrestrial reactions. It produces less total energy (11.3 MeV) than D-T fusion (17.6 MeV), and the energy is split between one alpha particle and two neutrons. D-T fusion has only two products, and conservation of momentum forces the neutron to exit at 4 times the speed that the alpha does, I think 17% of speed of light, which makes the neutron carry 4/5 of the fusion energy. These extremely fast and energetic neutrons spread the fission chain reaction faster, and produce fissions that themselves release larger number of neutrons. T-T fusion will produce less energetic neutrons. The initiation temperature or temperature-reaction curve for T-T is not given but may be higher than D-T. Given that deuterium is much cheaper, and can be handled in the same way as tritium, there is little reason not to include deuterium with tritium.
Ivy Mike's secondary was mostly deuterium, so there was certainly deuterium present. It is hard to say what the tritium was intended for with out more information. The tritium would reach higher thermal velocities than uranium or fission products because it is lighter, so some may have been ejected into the surrounding deuterium at high speed, where it might fuse and supply heat and neutrons. Or, since the test was an experiment, it may have been included simply to facilitate some measurements. Anyway, a secondary is a very different case than a primary, and is not what is meant by "boosted fission weapon".
Also, the radiation implosion of the secondary is supposed to avoid heating the fusion fuel too much, because that would interfere with the goal of maximum compression. Once maximum compression is reached, then you want to quickly raise the temperature to initiate fusion.
Too much neutron-absorbing 6Li in the center of a primary would raise the critical mass of plutonium needed for criticality, which would detract from boosting's reduction of the plutonium requirement to reduce predetonation insensitivity. -- JWB ( talk) 04:13, 25 November 2007 (UTC)
This discussion is wandering around too much. Here some facts I have nailed down with 99%-100% certainty:
One that is taken seriously but may be wrong:
And here is one I did not make up but which needs sourcing or rebutting:
An example of converging waves producing remarkably high temperatures appears in
Sonoluminescence.
Man with two legs ( talk) 10:59, 25 November 2007 (UTC)
I have posted a question on this at User_talk:Georgewilliamherbert. He knows something about this and may be able to shed light on it. Man with two legs ( talk) 16:09, 25 November 2007 (UTC)
I will post some more intelligent replies later, but...
Solid Li-D fission stage boosting has been demonstrated - it's known as "pill boosting". It's described as "much harder" than gas boosting and modern warhead designs generally include features which are presumed to be part of gas boosting systems. How prevalent it was in any generation of deployed weapons is currently hard to guess based on purely public information.
Fusion boosting is more important to avoid predetonation than to make weapons immune to high radiation environments, though both are advantages.
Don't take the warhead diagrams and Mark-28 internal details too literally. The drawings are oversimplified and slightly wrong.
In terms of whether you'd boost a secondary's sparkplug with pure T or D-T mix, it's the same logic that applies to primaries. Modern weapons probably use D-T for both.
As far as I know, nobody has used shockwave imploding the gas to start any useful fusion reaction in a test or deployed nuclear weapon. Under ideal conditions it may be possible; the inside of a realistic bomb is likely not ideal enough.
Anyways, just a few comments off the top of my head. Back to the grindstone. Georgewilliamherbert ( talk) 00:31, 27 November 2007 (UTC)
I have rewritten most of it. Positive criticism welcome. Man with two legs 22:43, 25 May 2007 (UTC)
Apparently inclusion in this article was motivated by a final comment at the FAS site:
"This design should probably be considered distinct from other classes of nuclear weapons. This design is something of a hybrid and could be considered either a type of boosted fission device, or a one-stage type of fission-fusion-fission bomb."
In actual usage "boosted fission weapon" always refers to a normal fission bomb with a small amount of fusion boosting at the center.
Boosting is used in all modern nuclear weapons, while Alarm Clock/Sloika designs are only of historical interest and were deployed briefly if at all.
The "one-state fission-fusion-fission bomb" is somewhat more accurate. The secondary of a radiation implosion weapon uses the same arrangement.
On the other hand if Alarm Clock can be considered a boosted fission device, so can staged thermonuclear weapons, which usually also derive most of their yield from fission.
I am going to remove the section from the article. -- JWB ( talk) 01:30, 1 January 2008 (UTC)
Li-D requires similar compression to D-D; in fact according to NWFAQ 4.4.5.3.2.1 Li-D relies on D-D for its initial neutrons (so requires the same temperature and compression) and fission neutrons do not play a significant role. So there is little difference.
Arnold pp. 86-87 is quoting British scientist Keith Roberts speculating in 1955 without full knowledge of the American program. As Arnold notes on p. xiii, the British at the time were confused and inconsistent in their use of nuclear weapon terminology. And on p. 223 she defines boosted bombs in a way that would include most later thermonuclear weapons.
In the weapons designs the US standardized on by the 1960s and deployed in the tens of thousands to the exclusion of anything else, "boosted fission weapon" always refers to small amounts of fusion fuel inside the primary's pit. In contrast the British experiments were a short-lived dead end, abandoned after the US agreed to share its technology.
I think it is fair to say that while "boosting" may have been used early on to refer to various uses of fusion to supply neutrons for fission, "boosted (fission) weapon" and "boosting" have more specific connotations in the context of the actual US nuclear arsenal and program, as it stabilized after the experiments of the first few years. -- JWB ( talk) 13:30, 6 January 2008 (UTC)
1. This article has been rated Start-Class and has a warning about lack of sources.
2. The bulk of this information has been incorporated into Nuclear weapon design where the reader can see it in a useful broader context.
3. Instead of fixing it and bringing it up to acceptable quality, should it be simply eliminated?
HowardMorland ( talk) 12:28, 8 May 2008 (UTC)
Teller-Ulam design, on the other hand, is closer to a duplicate article on the whole topic, though it still has some difference in emphasis.
One split that has occurred to me as reasonable is an article on History of nuclear weapons vs. a Nuclear weapon design that concentrates on modern designs. --18:01, 8 May 2008 (UTC)
Early thermonuclear weapon designs such as the Joe-4, the Soviet "Layer Cake", used large amounts of fusion to induce fission in the uranium-238 atoms that make up depleted uranium.
These weapons had a fissile core surrounded by a layer of lithium-6 deuteride, in turn surrounded by a layer of depleted uranium. Some designs (including the layer cake) had several alternate layers of these materials.
The Soviet Layer Cake was similar to the American Alarm Clock, which was never built, and the British Green Bamboo, which was built but never tested.
When this type of bomb explodes, the fission of the highly enriched uranium or plutonium core creates neutrons, some of which escape and strike atoms of lithium-6, creating tritium.
At the temperature created by fission in the core, tritium and deuterium can undergo thermonuclear fusion without a high level of compression. The fusion of tritium and deuterium produces a neutron with an energy of 14 MeV—a much higher energy than the 1 MeV of the neutron that began the reaction. This creation of high-energy neutrons, rather than energy yield, is the main purpose of fusion in this kind of weapon.
This 14 MeV neutron then strikes an atom of uranium-238, causing fission: without this fusion stage, the original 1 MeV neutron hitting an atom of uranium-238 would probably have just been absorbed. This fission then releases energy and also neutrons, which then create more tritium from the remaining lithium-6, and so on, in a continuous cycle. Energy from fission of uranium-238 is useful in weapons: both because depleted uranium is very much cheaper than highly enriched uranium and because it cannot go critical and is therefore less likely to be involved in a catastrophic accident.
This kind of thermonuclear weapon can produce up to 20% of its yield from fusion, with the rest coming from fission and is limited in yield to less than one megaton of TNT (4 PJ) equivalent. Joe-4 yielded 400 kilotons of TNT (1.7 PJ). In comparison, a true hydrogen bomb produces typically 50% of its yield from fusion, with 97% having been achieved, and there is no upper limit to its explosive yield.
There is a source and some usable content at Tritium#Boosting that could be moved or copied here. The source by Hisham Zerriffi says "the estimated quantity needed is 4 grams per warhead." -- Petri Krohn ( talk) 13:52, 21 November 2010 (UTC)
This article is not about multi-stage weapons, and yet it has a photo of one being tested (Ivy Mike). 180.200.183.94 ( talk) 11:19, 27 February 2015 (UTC)
Hello fellow Wikipedians,
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Cheers.— cyberbot II Talk to my owner:Online 03:49, 10 January 2016 (UTC)
There is no link to a German article, and I do not know how to edit links, so maybe somebody can help? Deutsch ---- https://de.wikipedia.org/wiki/Kernwaffentechnik#Geboostete_Spaltbomben
The German article is organized in a different manner. Boosted weapons is a section of "nuclear weapon technology". The link I'm giving is to the appropriate section.
76.254.31.171 ( talk) 06:33, 17 January 2017 (UTC)
Some of this article is very misguided. The problems seem so consistently wrong in the following quote that it is hard to imagine it is not intentionally wrong: . '....Deuterium-tritium fusion neutrons are extremely energetic, seven times more energetic than an average fission neutron, which makes them much more likely to be captured in the fissile material and lead to fission. This is due to several reasons: Their high velocity creates the opposite of time absorption: time magnification. When these energetic neutrons strike a fissile nucleus, a much larger number of secondary neutrons are released by the fission (e.g. 4.6 vs 2.9 for Pu-239). The fission cross section is larger both in absolute terms, and in proportion to the scattering and capture cross section...' . Not one of those supposed reasons is without serious problems.
The first reason, 'time magnification' is a made-up techno-sounding term. Note there is no link to any such buzz word in wikipedia. Note there is no footnote number for a supporting link for this or any of the claims in this section. Perhaps the author was dreaming about the relativistic effect known as 'time dilation'. If that was it, correcting the name won't help. Time dilation would delay the beta decay of free neutrons, but the halflife of that is many orders of magnitude higher than the processes discussed here and does not have any meaningful effect for nuclear weapons. . The second supposed reason fails because it is not related causally to the question it is supposed to answer, namely, why the more energetic d-t fusions neutrons might be more likely to be captured in fissile matetial and result in fission. The additional fission neutrons produced by d-t fusion neutrons is a result and not a cause of absorption. . The third supposed reason is just flat wrong. With the possible exception of u238 over very specific ranges, the absorption and fission crosssections are smaller at higher energies over an range of significance. . . Please review and delete this section. You can try to find support for those claims in question, but you will be looking a long time, so better to take out the offending inaccuracies in the interim. . 98.183.55.219 ( talk) 18:19, 17 March 2017 (UTC)BGriffin
I believe this is the technique used in the Tom Clancy book, The Sum Of All Fears. In the book, they discuss recovering a plutonium ingot from a Mark 12 bomb "lost" in the Yom Kippur war. The bulk of the story is about a former Soviet nuclear scientist and his protege that use metallurgical methods to reshape the ingot to produce a high yield weapon for some terrorists. At one point, they obtain some boosting fuel (it's been a while, could have been Lithium) that adds significant neutrons in order to make the explosion go from a 10Kt yield to a 400Kt yield. I read the Sum Of All Fears Wikipedia article just now, and it omits these details. Anyway, my point is, you might consider adding an "in the literature" section to call out to this. Maybe someone with more recent knowledge of the book can shore up my description. — Preceding unsigned comment added by 96.255.18.130 ( talk) 11:18, 3 April 2017 (UTC)
Lithium7, Deuterium, and Tritium participate in (n,2n) neutron doubling reactions. Deuterium splits circa 2MeV into proton and neutron. Beryllium9 generates neutrons from high MeV alpha emission in Polonium210/Beryllium neutron sources. Nazi Germany sought to enhance natural Uranium by adding “light metals” to increase Uranium neutron flux. Shjacks45 ( talk) 00:03, 16 November 2019 (UTC)
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As I understand it, the usual configuration of a tritium boosted weapon is that deuterium (D) and tritium (T) are placed in the centre of the pit (ie the core of plutonium or highly enriched unranium) of an implosion-type weapon. The shockwave of the implosion passes into the pit and produces a very high temperature in the centre sufficient to ignite thermonuclear fusion in the DT mix. The fusion reactions give off a burst of neutrons which initiate the fission chain reaction more quickly than would spontaneous fission alone. This increases the amount of fission that can occur in the brief time before the pit blows itself apart. The thermonuclear yield is insignificant, but the yield of the fission reaction is greatly increased. Man with two legs 14:12, 11 October 2005 (UTC)
I believe it takes not just the implosion energy from conventional explosives, but fission energy from the early stages of the fission chain reaction, to start fusion. After this, both fission and fusion proceed, the fission assisting the fusion by continuing heating and compression, and the fusion assisting the fission by radiating fast neutrons. As the fission fuel depletes and also explodes outward, it falls below the density needed to stay critical by itself, but the fusion neutrons keep fission going for longer than it would otherwise.
Besides increased yield (for the same amount of fission fuel with vs. without boosting) and the possibility of variable yield (by varying the amount of fusion fuel), possibly even more important advantages are allowing the weapon (or primary of a weapon) to have a smaller amount of fission fuel (reducing the risk of predetonation) and more relaxed requirements for implosion.
Also, I believe all boosting of primaries is done with gas, not 6LiD, probably because the latter is not a net producer of neutrons, and would not provide the quick neutron boost that DT fusion does. -- JWB ( talk) 07:19, 22 November 2007 (UTC)
The Nuclear Weapons Archive you gave discusses fusion via chemical explosive implosion farther down the page and says it's not practical.
The external neutron generator is the initiator.
“ | A somewhat similar approach is to use the implosion to initiate a neutron generating fusion reactions with tritium and deuterium (described in Section 2.2 below). It may seem surprising that this can be made to work, given the well known fact that fission explosions are required to produce the temperatures that fusion reactions normally need. Three considerations overcome this obstacle. First, an exceedingly low rate of fusion is actually required. One neutron (and thus one fusion) every 10 nanoseconds is sufficient, a rate that is only some 10^-24 as fast as an actual fusion explosion would need. Second, implosions focus energy and can reach very high temperatures near the center. Theoretically the temperature at the center is infinitely high, but lack of perfect symmetry reduces this. Even so, a high precision implosion can reach temperatures of several hundred thousand degrees C. Third, the velocity of atoms in a gas or plasma is a statistical (Maxwellian) distribution. A very small portion of the atoms can greatly exceed the average energy. Thus enough atoms in the D-T mixture near the center can reach fusion energies to produce the required rate of neutron production. This type of implosion initiator is even more difficult to engineer than the Be/Po-210 type since the very high precision implosion is required to achieve the required symmetry. The major advantage is that the short half-life Po-210 is not needed. | ” |
T-T fusion is listed at Nuclear fusion#Criteria and candidates for terrestrial reactions. It produces less total energy (11.3 MeV) than D-T fusion (17.6 MeV), and the energy is split between one alpha particle and two neutrons. D-T fusion has only two products, and conservation of momentum forces the neutron to exit at 4 times the speed that the alpha does, I think 17% of speed of light, which makes the neutron carry 4/5 of the fusion energy. These extremely fast and energetic neutrons spread the fission chain reaction faster, and produce fissions that themselves release larger number of neutrons. T-T fusion will produce less energetic neutrons. The initiation temperature or temperature-reaction curve for T-T is not given but may be higher than D-T. Given that deuterium is much cheaper, and can be handled in the same way as tritium, there is little reason not to include deuterium with tritium.
Ivy Mike's secondary was mostly deuterium, so there was certainly deuterium present. It is hard to say what the tritium was intended for with out more information. The tritium would reach higher thermal velocities than uranium or fission products because it is lighter, so some may have been ejected into the surrounding deuterium at high speed, where it might fuse and supply heat and neutrons. Or, since the test was an experiment, it may have been included simply to facilitate some measurements. Anyway, a secondary is a very different case than a primary, and is not what is meant by "boosted fission weapon".
Also, the radiation implosion of the secondary is supposed to avoid heating the fusion fuel too much, because that would interfere with the goal of maximum compression. Once maximum compression is reached, then you want to quickly raise the temperature to initiate fusion.
Too much neutron-absorbing 6Li in the center of a primary would raise the critical mass of plutonium needed for criticality, which would detract from boosting's reduction of the plutonium requirement to reduce predetonation insensitivity. -- JWB ( talk) 04:13, 25 November 2007 (UTC)
This discussion is wandering around too much. Here some facts I have nailed down with 99%-100% certainty:
One that is taken seriously but may be wrong:
And here is one I did not make up but which needs sourcing or rebutting:
An example of converging waves producing remarkably high temperatures appears in
Sonoluminescence.
Man with two legs ( talk) 10:59, 25 November 2007 (UTC)
I have posted a question on this at User_talk:Georgewilliamherbert. He knows something about this and may be able to shed light on it. Man with two legs ( talk) 16:09, 25 November 2007 (UTC)
I will post some more intelligent replies later, but...
Solid Li-D fission stage boosting has been demonstrated - it's known as "pill boosting". It's described as "much harder" than gas boosting and modern warhead designs generally include features which are presumed to be part of gas boosting systems. How prevalent it was in any generation of deployed weapons is currently hard to guess based on purely public information.
Fusion boosting is more important to avoid predetonation than to make weapons immune to high radiation environments, though both are advantages.
Don't take the warhead diagrams and Mark-28 internal details too literally. The drawings are oversimplified and slightly wrong.
In terms of whether you'd boost a secondary's sparkplug with pure T or D-T mix, it's the same logic that applies to primaries. Modern weapons probably use D-T for both.
As far as I know, nobody has used shockwave imploding the gas to start any useful fusion reaction in a test or deployed nuclear weapon. Under ideal conditions it may be possible; the inside of a realistic bomb is likely not ideal enough.
Anyways, just a few comments off the top of my head. Back to the grindstone. Georgewilliamherbert ( talk) 00:31, 27 November 2007 (UTC)
I have rewritten most of it. Positive criticism welcome. Man with two legs 22:43, 25 May 2007 (UTC)
Apparently inclusion in this article was motivated by a final comment at the FAS site:
"This design should probably be considered distinct from other classes of nuclear weapons. This design is something of a hybrid and could be considered either a type of boosted fission device, or a one-stage type of fission-fusion-fission bomb."
In actual usage "boosted fission weapon" always refers to a normal fission bomb with a small amount of fusion boosting at the center.
Boosting is used in all modern nuclear weapons, while Alarm Clock/Sloika designs are only of historical interest and were deployed briefly if at all.
The "one-state fission-fusion-fission bomb" is somewhat more accurate. The secondary of a radiation implosion weapon uses the same arrangement.
On the other hand if Alarm Clock can be considered a boosted fission device, so can staged thermonuclear weapons, which usually also derive most of their yield from fission.
I am going to remove the section from the article. -- JWB ( talk) 01:30, 1 January 2008 (UTC)
Li-D requires similar compression to D-D; in fact according to NWFAQ 4.4.5.3.2.1 Li-D relies on D-D for its initial neutrons (so requires the same temperature and compression) and fission neutrons do not play a significant role. So there is little difference.
Arnold pp. 86-87 is quoting British scientist Keith Roberts speculating in 1955 without full knowledge of the American program. As Arnold notes on p. xiii, the British at the time were confused and inconsistent in their use of nuclear weapon terminology. And on p. 223 she defines boosted bombs in a way that would include most later thermonuclear weapons.
In the weapons designs the US standardized on by the 1960s and deployed in the tens of thousands to the exclusion of anything else, "boosted fission weapon" always refers to small amounts of fusion fuel inside the primary's pit. In contrast the British experiments were a short-lived dead end, abandoned after the US agreed to share its technology.
I think it is fair to say that while "boosting" may have been used early on to refer to various uses of fusion to supply neutrons for fission, "boosted (fission) weapon" and "boosting" have more specific connotations in the context of the actual US nuclear arsenal and program, as it stabilized after the experiments of the first few years. -- JWB ( talk) 13:30, 6 January 2008 (UTC)
1. This article has been rated Start-Class and has a warning about lack of sources.
2. The bulk of this information has been incorporated into Nuclear weapon design where the reader can see it in a useful broader context.
3. Instead of fixing it and bringing it up to acceptable quality, should it be simply eliminated?
HowardMorland ( talk) 12:28, 8 May 2008 (UTC)
Teller-Ulam design, on the other hand, is closer to a duplicate article on the whole topic, though it still has some difference in emphasis.
One split that has occurred to me as reasonable is an article on History of nuclear weapons vs. a Nuclear weapon design that concentrates on modern designs. --18:01, 8 May 2008 (UTC)
Early thermonuclear weapon designs such as the Joe-4, the Soviet "Layer Cake", used large amounts of fusion to induce fission in the uranium-238 atoms that make up depleted uranium.
These weapons had a fissile core surrounded by a layer of lithium-6 deuteride, in turn surrounded by a layer of depleted uranium. Some designs (including the layer cake) had several alternate layers of these materials.
The Soviet Layer Cake was similar to the American Alarm Clock, which was never built, and the British Green Bamboo, which was built but never tested.
When this type of bomb explodes, the fission of the highly enriched uranium or plutonium core creates neutrons, some of which escape and strike atoms of lithium-6, creating tritium.
At the temperature created by fission in the core, tritium and deuterium can undergo thermonuclear fusion without a high level of compression. The fusion of tritium and deuterium produces a neutron with an energy of 14 MeV—a much higher energy than the 1 MeV of the neutron that began the reaction. This creation of high-energy neutrons, rather than energy yield, is the main purpose of fusion in this kind of weapon.
This 14 MeV neutron then strikes an atom of uranium-238, causing fission: without this fusion stage, the original 1 MeV neutron hitting an atom of uranium-238 would probably have just been absorbed. This fission then releases energy and also neutrons, which then create more tritium from the remaining lithium-6, and so on, in a continuous cycle. Energy from fission of uranium-238 is useful in weapons: both because depleted uranium is very much cheaper than highly enriched uranium and because it cannot go critical and is therefore less likely to be involved in a catastrophic accident.
This kind of thermonuclear weapon can produce up to 20% of its yield from fusion, with the rest coming from fission and is limited in yield to less than one megaton of TNT (4 PJ) equivalent. Joe-4 yielded 400 kilotons of TNT (1.7 PJ). In comparison, a true hydrogen bomb produces typically 50% of its yield from fusion, with 97% having been achieved, and there is no upper limit to its explosive yield.
There is a source and some usable content at Tritium#Boosting that could be moved or copied here. The source by Hisham Zerriffi says "the estimated quantity needed is 4 grams per warhead." -- Petri Krohn ( talk) 13:52, 21 November 2010 (UTC)
This article is not about multi-stage weapons, and yet it has a photo of one being tested (Ivy Mike). 180.200.183.94 ( talk) 11:19, 27 February 2015 (UTC)
Hello fellow Wikipedians,
I have just added archive links to one external link on
Boosted fission weapon. Please take a moment to review
my edit. If necessary, add {{
cbignore}}
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nobots|deny=InternetArchiveBot}}
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This message was posted before February 2018.
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(last update: 5 June 2024).
Cheers.— cyberbot II Talk to my owner:Online 03:49, 10 January 2016 (UTC)
There is no link to a German article, and I do not know how to edit links, so maybe somebody can help? Deutsch ---- https://de.wikipedia.org/wiki/Kernwaffentechnik#Geboostete_Spaltbomben
The German article is organized in a different manner. Boosted weapons is a section of "nuclear weapon technology". The link I'm giving is to the appropriate section.
76.254.31.171 ( talk) 06:33, 17 January 2017 (UTC)
Some of this article is very misguided. The problems seem so consistently wrong in the following quote that it is hard to imagine it is not intentionally wrong: . '....Deuterium-tritium fusion neutrons are extremely energetic, seven times more energetic than an average fission neutron, which makes them much more likely to be captured in the fissile material and lead to fission. This is due to several reasons: Their high velocity creates the opposite of time absorption: time magnification. When these energetic neutrons strike a fissile nucleus, a much larger number of secondary neutrons are released by the fission (e.g. 4.6 vs 2.9 for Pu-239). The fission cross section is larger both in absolute terms, and in proportion to the scattering and capture cross section...' . Not one of those supposed reasons is without serious problems.
The first reason, 'time magnification' is a made-up techno-sounding term. Note there is no link to any such buzz word in wikipedia. Note there is no footnote number for a supporting link for this or any of the claims in this section. Perhaps the author was dreaming about the relativistic effect known as 'time dilation'. If that was it, correcting the name won't help. Time dilation would delay the beta decay of free neutrons, but the halflife of that is many orders of magnitude higher than the processes discussed here and does not have any meaningful effect for nuclear weapons. . The second supposed reason fails because it is not related causally to the question it is supposed to answer, namely, why the more energetic d-t fusions neutrons might be more likely to be captured in fissile matetial and result in fission. The additional fission neutrons produced by d-t fusion neutrons is a result and not a cause of absorption. . The third supposed reason is just flat wrong. With the possible exception of u238 over very specific ranges, the absorption and fission crosssections are smaller at higher energies over an range of significance. . . Please review and delete this section. You can try to find support for those claims in question, but you will be looking a long time, so better to take out the offending inaccuracies in the interim. . 98.183.55.219 ( talk) 18:19, 17 March 2017 (UTC)BGriffin
I believe this is the technique used in the Tom Clancy book, The Sum Of All Fears. In the book, they discuss recovering a plutonium ingot from a Mark 12 bomb "lost" in the Yom Kippur war. The bulk of the story is about a former Soviet nuclear scientist and his protege that use metallurgical methods to reshape the ingot to produce a high yield weapon for some terrorists. At one point, they obtain some boosting fuel (it's been a while, could have been Lithium) that adds significant neutrons in order to make the explosion go from a 10Kt yield to a 400Kt yield. I read the Sum Of All Fears Wikipedia article just now, and it omits these details. Anyway, my point is, you might consider adding an "in the literature" section to call out to this. Maybe someone with more recent knowledge of the book can shore up my description. — Preceding unsigned comment added by 96.255.18.130 ( talk) 11:18, 3 April 2017 (UTC)
Lithium7, Deuterium, and Tritium participate in (n,2n) neutron doubling reactions. Deuterium splits circa 2MeV into proton and neutron. Beryllium9 generates neutrons from high MeV alpha emission in Polonium210/Beryllium neutron sources. Nazi Germany sought to enhance natural Uranium by adding “light metals” to increase Uranium neutron flux. Shjacks45 ( talk) 00:03, 16 November 2019 (UTC)