Open main menu
Thermonuclear weapon is a former featured article candidate. Please view the links under Article milestones below to see why the nomination failed. For older candidates, please check the archive.
Article milestones
DateProcessResult
August 10, 2005Peer reviewReviewed
December 16, 2005Featured article candidateNot promoted
A fact from this article appeared on Wikipedia's Main Page in the "Did you know?" column on July 25, 2005.
The text of the entry was: Did you know ...that the Teller-Ulam design is considered "the secret of the hydrogen bomb"?
Current status: Former featured article candidate

Comment on India's capability sectionEdit

Section claims that "Dr. Samar Mubarakmand asserted that Shakti-1 was a successful test,". It should be noted that Dr Samar Mubarakband is a Pakistani scientist. He can not in anyway be involved in Indian tests.

Yes, you're correct, and someone has made that notation. And as far as I can tell that India section statement is otherwise just plain wrong, in that it would appear that Pakistani scientist Dr. Samar Mubarakmand was disputing the Indian claim of a successful thermonuclear device at the Shatki-1 test, not asserting that it was a successful test! https://defence.pk/pdf/threads/pakistans-nuclear-and-missile-assets-myth-vs-reality.8651/page-4 about half-way down the page at Shatki-1 (approx. 66 'paragraphs' down), "...on the basis of the yield value from the detonation." . Whether his disagreement belongs in the India section I can't address. UnderEducatedGeezer (talk) 21:34, 31 August 2018 (UTC)

Basic principle and Summary sections: lithium deuteride, no need for tritium?Edit

Just reading the article, with no other specific knowledge, I see that the Basic principle section, referring to the secondary, fusion section of the H-bomb, says (bold is mine), "Inside this is the fusion fuel itself, usually a form of lithium deuteride, which is used because it is easier to weaponize than liquefied tritium/deuterium gas.", but the Summary section for that Basic principle section says (again, bold is added by me), "...fission chain reaction...supplying neutrons that react with lithium to create tritium for fusion." Other readings I've found ( http://www.atomicarchive.com/Fusion/Fusion2.shtml ) do suggest that lithium itself can be transmuted by incident neutrons into tritium, as suggested in the Summary section, so if that's true, shouldn't the fact that no actual initial tritium is needed in the secondary, because it's produced in the secondary by the fission explosion acting on the lithium deuteride there, be explained in the parent 'Basic principle' section? In other words, lithium deuteride is not just easier to use, it's all that's needed to provide the helpful tritium, at least in the secondary; it seems unclear if the same situation prevails in the core of the primary. UnderEducatedGeezer (talk) 02:13, 11 June 2018 (UTC)

Before anyone changes our article to say "lithium deuteride is not just easier to use, it's all that's needed to provide the helpful tritium, at least in the secondary", the editor would have to show where reliable secondary sources say that. Even if facts supported by reliable sources suggest such a thing, we can't (under the WP:SYNTH guideline, which I suggest reading) conclude it's true unless reliable secondary sources specifically say it's true.
"The US Department of Energy's Restricted Data Declassification Decisions 1946 to the Present (RDD-7)", lists among declassified information on tritium, "C. Tritium... 11 The fact that compounds of Li6 containing tritium are used in the design of weapons as TN fuel. (72-11)". The source doesn't say whether such compounds are or are not present in thermonuclear weapon secondaries. We can't change the article to say "lithium deuteride is not just easier to use, it's all that's needed to provide the helpful tritium, at least in the secondary" unless a reliable secondary source (see WP:SECONDARY) specifically says that.
I strongly suggest if you find such a source, you bring it up here in the article's talk page before making any changes. Thanks! loupgarous (talk) 03:25, 26 August 2018 (UTC)
You are of course completely correct, speculation is not fact and speculation should never be added to the wiki article itself. Thank you for pointing this out, and for suggesting referencing to source material, if any exists and could be found, before any addition relating to this conjecture would be made in the article. I just thought to bring the lithium-only conjecture up here in talk in case anyone might know or find any info on it. But it's good of you to remind people like me to not be too bold, such reminders really can be necessary, thank you! UnderEducatedGeezer (talk) 01:20, 27 August 2018 (UTC)
Just making sure everyone understood that (which is why I said "Before anyone changes... " - not directed solely at you, but at less-experienced editors who might be struck by the excellent logic of your suggestion. And you've got a good idea there, bringing this out and asking other folks for help.
Richard Rhodes' history of the thermonuclear weapon Dark Sun mentions tritium being loaded into the "sparkplug" of Ivy Mike's secondary. He doesn't say it explicitly, but (hopefully some more knowledgeable editor than us can point us to is a source to confirm this) the tritium in the Ivy Mike sparkplug was likely to fusion-boost the sparkplug and make it a more efficient source of X-rays to compress the deuterium in the central cavity of the secondary. A source to confirm that would be fantastic.
You're likely right and lithium-6 enriched deuteride is all you need (in the Castle Bravo test of the "dry", lithum deuteride secondary, the lithium-7 that was just supposed to be along for the ride actually captured a neutron and emitted two each time, driving the fusion reactions so much harder than planned that its nuclear explosive yield went three times its five-megaton design to fifteen megatons). We just need a source to confirm that. And really, thanks for bringing this issue up - we'd have a stronger article if the fact were out in the public domain and we could cite it. Hopefully, another editor knows where and can help us. loupgarous (talk) 08:16, 31 August 2018 (UTC)
[1] suggests a secondary source: Arnold, Lorna; Pyne, Katherine (2001). Britain and the H-bomb. Basingstoke, Hampshire: Palgrave. p. 18. ISBN 978-0-230-59977-2. OCLC 753874620.
Better: [2] Blades, David M.; Siracusa, Joseph M. (2014). A History of U.S. Nuclear Testing and Its Influence on Nuclear Thought, 1945-1963. Lanham, Maryland: Rowman & Littlefield. p. 60. ISBN 978-1-4422-3200-6. OCLC 867013161.
Hawkeye7 (discuss) 15:19, 31 August 2018 (UTC)
Thanks for the sources, Hawkeye7! In the back of my head (not citable here, of course) I remember reading an online retrospective on the British thermonuclear program (which actually had respectable thermonuclear yields before the 1958 mutual defense agreement with the US in which they got the Teller-Ulam design) in which it was mentioned that lithium was considered for use as the primary fusion fuel for thermonuclear weapons. I have to lay hands on your two texts (hopefully amazon.com's got them cheap, otherwise it's off to the county library for interlibrary loan) and also try to re-find that British Ministry of Supply web page I just described. Somewhere in those three sources, we'll find a citable passage to either affirm or deny the idea that tritium isn't strictly necessary for a thermonuclear detonation. And thanks again, UnderEducatedGeezer for getting this discussion started. loupgarous (talk) 20:45, 5 October 2018 (UTC)
And thank you, loupgarous and Hawkeye7 for finding my comment interesting enough to further investigate! My physics 'knowledge' goes back to a semester or two of Physics ~50 years ago for an (un-completed) Engineering degree, so my comment was just, 'hmmm, I wonder if...', in the hopes that more knowledgeable people might respond, and boy did you ever! :) . UnderEducatedGeezer (talk) 20:57, 9 October 2018 (UTC)
Glad to oblige! Anyway, finding promising books on the history of the British nuclear weapons program; British production of lithium-6 was so disappointing that they needed to trade plutonium to the US for six tonnes of refined lithium-6 as part of the UK-US Mutual Defense Agreement of 1958, according to Charles N. Hill's An Atomic Empire: A Technical History of the Rise and Fall of the British Atomic Energy Programme.
In page 97 of that book, Hill says "Tritium is not used in fusion devices (other than to improve the performance of the trigger stage)". That flies in the face of published data from The US Department of Energy, which declassified "The fact that compounds of Li6 containing tritium are used in the design of weapons as TN fuel." The only way to deconflict those sources would be to find another secondary source which describes lithium-6 tritide being used in the "spark plug" of a Teller-Ulam thermonuclear secondary as well as in fusion-boosting the fission primary, so that it's not acting as the fusion fuel in the secondary, just making the fissile devices as efficient as they can be.
Tritium is important in all Teller-Ulam thermonuclear weapons, but British thermonuclear test devices up to Grapple X (1.8 megaton yield) had spherical secondaries and were thus likely not Teller-Ulam designs (the early Teller-Ulam weapons had cylindrical secondaries). If we're looking for a thermonuclear weapon with little or no tritium in it, we're probably talking about Soviet, British, Chinese or French designs. loupgarous 07:37, 11 October 2018 (UTC)
Going back to Richard Rhodes' The Making of the Atomic Bomb (pp. 419-420 of the trade paperback edition)

"There was serious trouble with Teller's D+D Super. The reaction would proceed too slowly to reach ignition before the fission trigger blew the assembly apart. Konopinski came to the rescue. "Konopinski suggested that, in addition to deuterium, we should investigate the reactions of the heaviest form of hydrogen, tritium." This, Teller explains, was at that time, "only... a conversational guess." One tritium reaction of obvious interest was the fusion of a deuterium nucleus with a tritium nucleus...

and goes on to describe how Lithiun-6 would have to be neutron activated to make tritium, since tritium doesn't occur in nature.
Going back to the sources we do have, and avoiding WP:SYNTH, we have good secondary sources stating that a D-D reaction alone was discarded early on (1942) as too slow to proceed before the primary blew a hypothetical D-D bomb apart, D-T fusion is at least crucial as the "spark plug" of a thermonuclear reaction (plenty of open-source material attests to that both for weapons and for fusion reactors that don't involve boron-11 + proton reactions or other such exotica). And we have the US Department of Energy themselves saying that tritium is used in theromnuclear weapon fuel.
Rhodes' mention of Konopinski's suggestion (of adding tritium to the hydrogen fusion mix for a faster, more enegetic reaction) and the Manhattan Project's core team of physicists' early rejection of just deuterium-deuterium fusion for a thermonuclear weapon (Teller's early "Super" concept at that point) will have to be enough. We ought, in our article, to omit the idea that you can just use lithium-6 deuteride as a thermonuclear fusion fuel without the addition of tritium till we get a good secondary source saying that explicitly. Thanks to everyone for their help! loupgarous (talk) 17:20, 15 April 2019 (UTC)

Semi-protected edit request on 8 July 2019Edit

Change "Dr. Samar Mubarakmand, a Pakistani nuclear physicist, asserted that Shakti-1 was a successful thermonuclear test"

to

"Dr. Samar Mubarakmand, a Pakistani nuclear physicist, asserted that Shakti-1 was a nuclear test not thermonuclear" 103.255.5.64 (talk) 08:22, 8 July 2019 (UTC)

  Partly done: I changed the sentence to reflect the info in the citation given, using the formulation ... asserted that if Shakti-I had been a thermonuclear test, the device had failed to fire. Thanks. —Nizolan (talk · c.) 01:32, 16 July 2019 (UTC)
(Incidentally it seems UnderEducatedGeezer pointed this out above almost a year ago, so I'm pinging him to let him know I made the change. —Nizolan (talk · c.) 01:33, 16 July 2019 (UTC))
Return to "Thermonuclear weapon" page.