Nazi Atomic weapons in 1943

reply to post by JimTSpock


A hybrid bomb of fission and fusion??? That's what that guy claimed?

AngryCymraeg
reply to post by JimTSpock

 

A hybrid bomb of fission and fusion??? That's what that guy claimed?

Yes, Spock. More accurately, the German approach to a nuclear detonation, at least in terms of the 1945 Ohrdurf explosion of a device designed and built by a team under the Army physicist Dr. Kurt Diebner, was one that probably used a form of "boosted fission". In simplest terms, boosted fission is a method of creating the same kind of overload of neutrons in a tiny space that was used by the first US atomic bombs. However, boosted fission achieves this effect by combining large numbers of neutrons from substances other than those found in the fissile target of "bomb fuel" itself. The immediate and cardinal advantage of such an approach is that it significantly reduces the amount of "bomb fuel" necessary to create a detonation in the first place.


Per Carey Sublette's outstanding article on the subject as archived on the Federation of American Scientists website, boosted fission actually achieves a momentary---and very small by comparison with true H-bombs---nuclear fusion reaction in the core of the bomb. The fusion only contributes 1 or 2% of the total yield of the boosted fission bomb, but causes far higher numbers of neutrons in the bomb fuel / core to fission than would be the case in a true, pure fission bomb such as Little Boy. A true, pure fission bomb utilizes ONLY the fissioning neutrons from its own organic or nominal critical mass to cause other neutrons to split from the uranium fuel. A boosted fission weapon uses BOTH neutrons as they fission from the bomb fuel AND neutrons from other substances, usually light nuclei such as Lithium-6 Deuteride or Tritium.


I have compared this approach elsewhere to the difference between two sports cars with identical stock engines, except that one of the engines has a turbocharger mounted on top of it. The difference is in the turbocharger, NOT in the engines themselves---except in this analogy, BECAUSE OF the turbocharger, the size of the engine in the second car could be scaled down dramatically while still providing the same, or even superior, power in comparison with the first car that has no turbocharger. Clumsy analogy, but maybe it helps.


For further reading: "New Light on Hitler's Bomb" by Mark Walker and Rainer Karlsch, archived on the Physics World website from 2005, and "Introduction to Nuclear Weapons Design" by Carey Sublette, archived on the Federation of American Scientists website.

sy.gunson

AngryCymraeg
reply to post by williamjpellas

 

The Oslo Report is extremely well-known and did NOT mention an Axis atomic bomb project.

The Oslo letter was received in November 1939.

The German Atomic bomb project was only begun in late 1939 in strict secrecy. Seimens only became involved with the Atomic bomb project through the Reichs Forschungsrat (RFR) in June 1942.

Right, Simon, but upthread you stated that the Oslo Report contained information about some part of the German nuclear weapons effort. Did you mean to say that, or was that a typo, perhaps? Understand, I am just trying to track down all of the sources you mention so I can, ideally, acquire them---along with others---for my own examination. Thanks much.

williamjpellas

sy.gunson

AngryCymraeg
reply to post by williamjpellas

 

The Oslo Report is extremely well-known and did NOT mention an Axis atomic bomb project.

The Oslo letter was received in November 1939.

The German Atomic bomb project was only begun in late 1939 in strict secrecy. Seimens only became involved with the Atomic bomb project through the Reichs Forschungsrat (RFR) in June 1942.

Right, Simon, but upthread you stated that the Oslo Report contained information about some part of the German nuclear weapons effort. Did you mean to say that, or was that a typo, perhaps? Understand, I am just trying to track down all of the sources you mention so I can, ideally, acquire them---along with others---for my own examination. Thanks much.

I'm familiar with the Oslo Report and I can confirm that it said nothing about atomic weapons.

williamjpellas
However, boosted fission achieves this effect by combining large numbers of neutrons from substances other than those found in the fissile target of "bomb fuel" itself. The immediate and cardinal advantage of such an approach is that it significantly reduces the amount of "bomb fuel" necessary to create a detonation in the first place.

For further reading: "New Light on Hitler's Bomb" by Mark Walker and Rainer Karlsch, archived on the Physics World website from 2005

In any nuclear weapon the nuclear fission reaction starts first from achieving critical mass of fissionable material and produces enough heat to start a nuclear fusion reaction if the weapon is a fusion-boosted fission weapon or a thermonuclear weapon. If you want to do the fusion reaction first you need cold fusion...but that's another story. Thus there is no reduction in the amount of fissionable material required for critical mass.

Types of nuclear weapons.

Pure fission weapons.
Gun-type assembly weapon - Little Boy
Implosion-type weapon - Trinity and Fat Man
Plutonium pit
Levitated-pit implosion
Two-point linear implosion
Two-point hollow-pit implosion

Fusion-boosted fission weapons.

Two-stage thermonuclear weapons.

www.atomicarchive.com...
en.wikipedia.org...
en.wikipedia.org...-boosted_fission_weapons

"Karlsch displays a catastrophic lack of understanding of physics," wrote physicist Michael Schaaf, author of a previous book about Nazi atomic experiments, in the Berliner Zeitung newspaper.

news.bbc.co.uk...

The fusion boosted fission nuclear weapon is a more advanced and complex design than the pure fission weapons which came from the Manhattan project and require more research and development. The US tested it's first fusion boosted weapon in 1951.

sy.gunson
reply to post by babybunnies

 

There is a concept called natural critical mass which US first generation nuclear weapons adopted for the methodology. USA abandoned weapons requiring critical mass in 1948. You need to research the Christie Core and levitated Plutonium pits to follow this further.

H-bombs were second generation nuclear weapons

Miniaturised boosted fission nukes were third generation nuclear weapons. Without third generation nukes ballistic nuclear weapons would be impossible.

If you read some of the public lectures by Edward Teller USA was greatly indebted to Nazi wartime research on Third Generation nuclear weapons for it's development of the H-bomb.

The fact is the Nazis adopted an entirely novel and different approach to the Allies and one which required far less fissile material therefore did not require a cumbersome Manhattan project.

It may be of interest that as of february 2013 North Korea which shares technology with iran and Jihadist groups test blasted a 7 kiloton Third Generation nuclear weapon using just 0.4 kilograms of uranium.

Los Alamos Laboratory and Lawrence Livermore laboratories are working with CERN on fourth (fifth?) generation nuclear weapon using anti-matter trapped in a cryogenic electromagnetic bottle. One in which a tiny speck of antimatter has the same explosive power as a a large H-bomb.



.

Anti-matter weapon? Really? Amazing. So the North Koreans made a nuke with 400 grams of uranium and it worked? How do you know that? Best post in the thread.

reply to post by JimTSpock



Karlsch himself may or may not have "a catastrophic lack of understanding of (nuclear weapons) physics". I suspect that he does not quite grasp exactly how certain types of weapons work. However, I am totally convinced that he is a good journalist and researcher and that he has uncovered a good deal of evidence and documentation that flies in the face of the more or less "conventional history" of WWII---or at least, of the end of WWII. Exactly how much evidence / documentation he has, and precisely where it leads, I am not yet sure. But I have seen enough to secure my interest in the topic and to lead me to a renewed and, hopefully, much more comprehensive investigation. In reading the naysayers in their attempted public execution of Karlsch and his ideas, I don't see a lot of specifics. Mostly just a lot of harrumph-harrumphing and saber rattling and how-dare-you-sirs. In other words, the same kind of crap they threw at Robert Wilcox and his book, Japan's Secret War. Not because they took issue with Wilcox's documentation or investigation or conclusions, but simply because his book called into question the phony secular "new left" pseudomorality about the War that came to dominate Western academia in the 1960s and, specifically, their constant retroactive handwringing and Marxist deconstructionism and mudslinging about the atomic missions against Japan. Which is a long winded way of saying, I'll wait until I read something by someone who has examined all of Karlsch's sources and then some, and who specifically debunks what he is saying---if it can be debunked---before I will join them in their, ahem, "conclusions".


Re: boosted fission. I don't think you quite have it, Spock, though I thank you for the useful list of various types of nuclear and thermonuclear weapons. I have discovered that there is a great deal of confusion about the precise meaning of the term "critical mass". In one sense of the term, every nuclear detonation can be said to have achieved "a critical mass". In other words, a "mass" of fissile material must go radioactively "critical" before it will explode (actually supercritical in the case of a bomb, as a reactor also "goes critical" but in slow motion in comparison with a bomb). However, NOT every type of atomic or thermonuclear weapon requires a nominal or organic critical mass in order to detonate.


Again: using only a pure fission bomb approach---a simple gun-type weapon---ONLY the neutrons in the organic or nominal critical mass of fissile material actually fission and split other atoms in order to cause an explosive release of energy. HOWEVER, if you can engineer it properly, it is possible---and in fact is today the world standard---to cause an explosion with the same kind of neutron overload in a confined space that you find in a fission bomb, except that you use OTHER FISSILE MATERIALS to add massive numbers of neutrons IN ADDITION TO the neutrons in the "bomb fuel" (the fissile core) of the weapon itself. The massive numbers of additional neutrons, as you might expect, cause massive numbers of additional uranium or plutonium atoms to fission, exponentially increasing the explosive yield of the bomb. This is true of both boosted fission and true "H-bombs", sometimes known as "three stage" or "fission-fusion-fission" bombs. I have found that there are often a number of different terms floating around in various books and on the internet that are used to describe the same phenomena, and it can be confusing when you read this or that source---often written by some kind of "insider" using all kinds of "wonkspeak". Which is why I recommend Carey Sublette's outstanding article "Introduction to Nuclear Weapons Physics", as it is far and away the clearest and most informative writing I have yet found on the subject.

reply to post by williamjpellas


All nuclear weapons require a critical mass of fissionable material to detonate, then further fusion increases the efficiency and yield, such as in a thermonuclear weapon.

simplethinking.com...

science.howstuffworks.com...

These 2 links have some good info and I've basically just said what's there.

Most of what you've said is absolutely correct except the fusion step does not decrease the critical mass required for detonation, it does increase the efficiency and yield. It's there in the links I've posted, which have some good info. What I've said so far is pretty basic.

williamjpellas
In other words, a "mass" of fissile material must go radioactively "critical" before it will explode (actually supercritical in the case of a bomb, as a reactor also "goes critical" but in slow motion in comparison with a bomb). However, NOT every type of atomic or thermonuclear weapon requires a nominal or organic critical mass in order to detonate.

The way I understood it was that the original definition of 'critical mass' corresponds to "how much do you need in a (mostly) spherical lump at standard density", i.e. essentially the Little Boy design. Fairly quickly they went to dynamic implosion designs and hollow geometries and arranged it so that the density increase from implosion and inertial confinement from stuff being flung together resulted in a condition which permitted criticality (i.e. chain reaction from fast fission where neutron induced fission rate of new nuclei exceeds losses, leading to exponential increase, at least at first) with less fissile material than would be necessary using a static geometry and standard density.

And in this sense the boosting adds additional neutrons at the moment of criticality which increases yields, but if criticality were not there (i.e. the exponent is not positive and is negative), the extra neutrons would just result in a stronger fizzle.

For a short time (before geometry changes due to explosive dissassembly), neutrons as a function of time is

N(t) = N_0 * exp(lambda t)

at criticality, lambda becomes > 0 for fast neutrons. Boosting, in effect, gives a pulse to N_0, and more of the assembly will be fissioned before explosive disassembly results in loss of criticality and end of chain reaction.

reply to post by mbkennel


That is my understanding and there are ways to decrease the mass required for the initial detonation.

Changing the point of criticality

en.wikipedia.org...

I imagine a lot of the info on nuclear weapons design would be highly classified.

The extra neutrons from boosting come from the fusion reaction which requires the initial fission to start.

reply to post by JimTSpock


Wow, love the information, kennel and Spock! Thank you both!


Kennel, yes, your description of the rapid progress in the early years of nuclear weapons engineering is consistent with what i have read in most sources. Thank you for your adroit summary! And Spock, you are saying that your sources indicate that both boosted fission and a true "H-bomb" (ie fission-fusion-fission) greatly increase both the efficiency and the yield of the nuclear explosion, but do not reduce the necessary size of the fissioning, supercritical mass? This is a key issue where the Schumann-Trinks design is concerned. I am trying to determine whether it was, in fact, a viable weapons design ie, would have worked with sufficient "bomb fuel"---I strongly suspect that it would have but I am not a physicist---and also whether it truly originated during WWII itself, or soon after the war (when it turned up in a French patent office of all places).


Again no offense meant, but I don't see where the sudden addition of massive numbers of neutrons would not result in at least a moderate reduction (and probably much more than that) of the necessary size of the "fissile target"---that is, the "bomb fuel" that is being bombarded by fast-fissioning neutrons to cause an explosion. As kennel points out, the structure of the fissile target / bomb fuel does come into play, meaning that there is a certain geometric configuration(s) that will enable the most efficient, or more efficient, reaction / explosion. But raw numbers of fissioning neutrons would still have to come into play as a very important factor if not the most important, it seems to me. There are numerous examples of small nuclear weapons that have been engineered in recent years, and obviously none of them needed anything like the "organic" or "nominal" or "natural" critical mass found in Little Boy and similar designs. Going back a few decades, there was the US Army "Dave Crockett" device, which was essentially an oversized nuclear bazooka. The warhead used by that weapon had a "critical mass" that was VERY small in comparison with both the original WWII US weapons and also when compared with most other postwar designs.


Yes, as was said above, one of the biggest problems in researching all of this stuff is that so much of it, even today, is highly classified. So we civilian pukes are more or less groping around---not in outright darkness, but certainly in twilight. I have been trying to find a reputable source who can comment definitively on the Schumann-Trinks design for the better part of a year now and can't find anyone. If anyone has any contacts who could help, I would greatly appreciate it.

williamjpellas
reply to post by seagull

 

Simon, of the possible areas of interest you have posted to this point, the one about which I know the least---next to nothing, really---is the "76 Zentner Bomb". Could you possibly give a brief summary of the nature of this weapon, ie, was it a uranium bomb, or something else, was it ever completed, was it tested, etc? I would also be interested to learn the identities of the top German scientists involved in its R&D, if you have that information. And of course, any sources you might have for the 76 Zentner project are much appreciated. Thanks again!

What I know really comes from a string of correspondence with German lawyer Dirk Finkemeier and his English friend Keith Sanders since January 2014. I ceased posting until i could get to the bottom of their claims.

Keith's father Fred Glyndwr Sanders was part of an RAOC unit attached to T-Force under the command of 8th Army DDOS. This unit reached Espelkamp on 4th April 1945 and at a varnish factory they found the entrance to an underground factory built underneath a nearby forest. In the 1950s a school was built over the site but pupils have been suffering radiation sickness so recently the German Government has been digging up the school grounds uncovering the concrete bunker.

Dirk initially told me a 3.8t atomic weapon was found at Espelkamp, but when I compared notes Keith Sanders, he corrected Dirk that this weapon was found in an underground complex near Goslar on 26 April 1945, then flown out by the Americans. Dirk was more specific and asserted the 3.8 tonne device was flown out in an aircraft flown by Charles Lindbergh. i am advised a document in the Library of congress refers to this, however I have no citation myself.

Charles Lindbergh was a German speaking aviation consultant to NAVTECHMISEU and is known to have participated in several interrogations relating to high technology German weapons. He was a qualified instructor on the B-24 Liberator bomber, so had the necessary flying skills.

To pursue their claim I did my own investigations of the American Little Boy bomb and found there was little credible evidence for Oak Ridge having enough HEU in April 1945. The Germans however had several underground facilities operating Uranium centrifuges which were thirty times more efficient and thirty times faster at enriching uranium that the K-25 gaseous diffusion plant at Oak Ridge.

It is very much their research and their sources and understandably they would not like me to poach what they have spent decades researching. they have given me some crumbs but I am in no position to enlarge much on their claims without doing my own research.

sy.gunson
found there was little credible evidence for Oak Ridge having enough HEU in April 1945.

except for this, which you ignore as it does not fit your silly claim....

As of January 1945 on any given day about 85 percent of some 864 Alpha calutron tanks operated to produce 258 grams-9 ounces-of 10 percent enriched product; at the same time 36 Beta tanks converted the accumulated Alpha product to 204 grams-7.2 ounces-per day of 80 percent enriched U235, sufficient enrichment to make a bomb. James Bryant Conant calculated in his handwritten history notes on January 6 that a kilogram of U235 per day would mean one gun bomb every six weeks. It follows that the gun bomb required about 42 kilograms-92.6 pounds, about 2.8 critical masses-of U235. Without further improvement the calutrons alone could produce that much material in 6.8 months, and Conant noted after conferring with Groves that "it looks as if 40-45 kg . . . will be obtained by July 1." Ernest Lawrence's monumental effort had succeeded; every gram of U235 in the one Little Boy that should be ready by mid-1945 would pass at least once through his calutrons.

The Making of the Atomic Bomb page 601....

reply to post by sy.gunson


I have a severe problem with your last post. 8th Army was nowhere near North-West Germany in April 1945. They were still the other side of the Alps. If you can't be bothered to get your facts straight then I have even more severe doubts about the rest of your unverified theory.

mbkennel, Spock:

Sorta.

The problem is in thinking that critical mass is a static number - it's not.

It's dependent on a number of things. Among them, the geometry of the material, the presence of 'poisons' that absorb neutrons, the use or not of a reflector, and the mean free neutron path. Diddle any of these, and you can make a non-critical mass become supercritical.

I would comment in depth on a few of these but I'm multiply NDAd on two of them. However, let's consider mean free neutron path. This is the big payoff variable, because it's got an exponent on one of the terms that defines it, and it's the term that the big boys diddle when they make the fireworks.

Basically, for any fixed set of the other variables, the mean free neutron path is dependent on the fissile material's characteristics, and there's not much you can do about that one. However, there is one variable you can alter, and that's density. The mean free neutron path is sensitive to the fissile density. The denser the material, the shorter the free path. If the bulk of the neutrons' paths end within the mass, it tends to be critical.There's a nice equation that deals with it in a more organized fashion, which has been tweaked and altered a tad since its inception. But the original one's still about right.

The critical mass is dependent on the mean free neutron path. The shorter the MFNP, the lower the critical mass. For an unshielded mass, the relationship between density and CM is roughly a square. The CM goes down more or less as the square of the relative density. Adding in a neutron reflector adds in more niftyness in the form of another exponent that gets tossed in. If you had a perfect neutron reflector, your CM approaches zero.

Adding in neutrons in the form of boost is a nice trick. As mbkennel says, it adds in neutrons at the beginning of the detonation. The supercritical mass acts as a sort of positive feedback amplifier while it's intact and still supercritical. The more neutrons you can input at this stage, the more you'll get back geometrically multiplied at the end.It's a way of increasing the total burn of the mass and makes the weapon not only more efficient but cleaner. You actually have to input more energy to get the fusion to go than you get back out of it, but the increased neutron flux pays you back handsomely.

For weapon systems that don't use boost, if you had one, you could get the same effect by just generating a lot more neutrons with your initiator. The tritium in boost gas and initiator gas (assuming you're using a neutron tube or zipper) is the reason that nukes need lots of maintenance. If you could get rid of it, there would be rejoicing and dancing about,because then one could put really high yield weaponry in places you can't readily maintain it,like space or the deep ocean or in someone's city park disguised as a clown statue or something. Something like that might be a real design goal, with lots of money attached.

Or you could just invent a nice switchable neutron reflecting field with 100% efficiency, and you could make nukes the size of a golfball.

reply to post by Bedlam


What do you make of this?

sites.google.com...

It's supposed to be the so-called Schumann-Trinks design which is completely different to a fusion boosted fission weapon, and down the bottom guess who the author is.

JimTSpock
reply to post by Bedlam

 

What do you make of this?

sites.google.com...

It's supposed to be the so-called Schumann-Trinks design which is completely different to a fusion boosted fission weapon, and down the bottom guess who the author is.

What an astonishing co-incidence! Oh wait...

AngryCymraeg

JimTSpock
reply to post by Bedlam

 

What do you make of this?

sites.google.com...

It's supposed to be the so-called Schumann-Trinks design which is completely different to a fusion boosted fission weapon, and down the bottom guess who the author is.

What an astonishing co-incidence! Oh wait...

Schumann & Trinks proposed to set up two conical hollow charges facing one another to implode a mixture of ingredients towards each other as two molten slugs. These slugs of Lithium-6 collided with each other at speeds up to 10 kilometres per second. With such pressures and temperatures, Lithium-6 in the presence of Deterium sheds neutrons in a massive rush, which artificially recreates the same critical mass effect obtained in a conventional nuclear warhead.

Well,you should fix this bit. Lithium-6 only creates neutrons when it's bombarded with neutrons, then compressed under absolutely awful pressures and temperatures in the presence of deuterium. It takes a LOT of neutrons to get that going, and a non-zero amount of time. Just putting it in the presence of deuterium doesn't get the job done. Even forming a plasma of it doesn't get the job done. And even IF you get it going somehow, it doesn't change the critical mass of any nearby fissiles. It would add neutrons to a supercritical mass if you had one, or if you had a lot of Li6-D that was very contained, you could use it to fission a mass of U238. The key to that is 'very contained'.

Your mechanism for Li6-D making neutrons is this - the Li6 has to be bombarded with a neutron which it has to capture, then after some time it fissions creating tritium and helium 4. Until you get that tritium, you got bupkis. Once you have enough of it, you start getting D-T fusion, and that's where the neutrons come from. But in order to get there, you've got to have it bombarded with neutrons long enough from outside to create the tritium, and then contain it while it fuses. That involves keeping the pressure very high and the temperature as well, in a Teller-Ulam weapon the neutron bombardment, compression and heating is done by a nuke ablating a cylindrical holraum on the outside while you fission a stick of plutonium up the middle on the inside. It's not the sort of thing you can do with a shaped chemical charge.

Bedlam Once you have enough of it, you start getting D-T fusion

Where does the energy come from to cause D-T fusion?

JimTSpock

Bedlam Once you have enough of it, you start getting D-T fusion

Where does the energy come from to cause D-T fusion?

If Sy.Gunson is to be believed, Nazi super-science!