HOMEbuilt H-Bombs? Fact or Fiction?

[RonRyan85]

There are a few magazines who seem to try and
increase sales with super-sensational covers that
are more exciting than the story inside. The August
issue of "Popular Mechanics" is one I am familar
with and the cover shouts:"America's Worst
Nightmare...HOMEBUILT H-BOMBS! Cold fusion
Technology enables anyone to build a nuke from
commonly available materials." The article tells
about an explosion that occurred in a cold fusion
lab and shows a number of ways to produce the
weapons grade uranium and speaks of the need
to produce TRITIUM for use in an H-bomb but
never goes into any details...of course.

My question is : Does this article and others
like it hold any merit? What does it take to do
what I consider a very difficult task of making a
neclear weapon from common materials?

(I know that a college student
wrote a paper for credit in the 1970's or 80's and
told in detail how to build an atomic bomb and
when the F.B.I. came and questioned him he
explained he got most of the information from
books he checked out of the local library and
calls he made to some scientists. (One problem
he asked about was the method used to compress
the uranium so it created a critical mass. The
scientist told him the way to do it.) :uhh:

 

[selfAdjoint]

The Popular Science article is over the top. 1. Cold fusion has yet to produce any noticable nuclear results. 2. It is hard to get fusion to make a big explosion, the obvious things either would not explode at all or would produce just a squiff. All the present designs use an atom bomb as a first stage to compresss the fusile materials sufficiently to attain real fusion.

The college student (he was actually a physics grad student) was hired by the government to try to design a nuclear bomb. He succeeded, as you said working off his own physics knowledge and open published material. (Actually there were two students, the first one got a good start but had to go back to school, the second one made the successful design).

The design was evaluated by experts, and they agreed it would have worked. Of course it was never built.

In spite of what I wrote above, I am very worried about private individuals, terrorists or otherwise, building fission bombs. The main difficulty is getting fissile material (purified U-235 or Plutonium). Purifiying U-235 from natural Uranium is a long and expensive process. AFAIK, Plutonium is only produced in nuclear reactors. Nevertheless, it is possible that a small group of individuals could do it.

 

[RonRyan85]

TO:selfAdjoint
Hyper Wave

Thanks for the interesting reply. As to the subject of terrorists obtaining weapons to
use against the USA or other countries,what do you think about the possibility of
former USSR "Suitcase Atomic Bombs" coming into their hands. We heard a lot about
these weapons a few years ago but not much lately. What do you think is the most
likely way that terrorists might get what they want? Another question I have for you
or others is: How many years can a "Suitcase Bomb" exist before the parts begin to
wear out and refuse to work?

 

[selfAdjoint]

This is a very good question.

The best way to get one would be bribery. Senator Lugar and others have desperately trying to get all the Russion and Ukranian loopholes closed, but the Bush administration shows no interest.

A suitcase bomb would probably feature U-235, I'm thinking it would use the same simplified construction as the A-bomb in an artillery shell.. The metal decays gradually by radioactivity, so it does have a finite shelf life. I would expect it to last several years. But I'm no expert. There are some real experts on nuclear weapons down on the Engineering forums; you might give them a try.

 

[rick1138]

There is a recent book out that makes the claim that 20 of the Ukranian "suitcase" nukes are missing and that some were obtained by Al Qaida in the late 1990's.

 

[Tau_Muon_PlanetEater]

First off, building a nuke is not difficult, its getting the materials needed to build it that is near to impossible without arrousing a response from intelligence agencies. U-235 is needed, and can only be obtained by milling the more common U-238. Milling involves a process that requires several football fields worth of space and extremely expensive equipment. Of course, you could get U-235 from nuclear facilities, but most of it would be impurely mixed with U-238. To start the runaway effect know as fission, the U-235 must be at least 97% pure, which no nuclear facility produces at that weapons grade purity.

Secondly, there are dozens of other elements needed to attain fission, like cadmium (heavily regulated), Plutonium (heavily regulated), and many others. Also, without extremely in depth blueprints, or technical know-how, you would never get the U-235 to properly implode. Also, its the last 2 or 3 fissions that create the huge mushroom cloud, and they are the most difficult to achieve.

 

[Chronos]

Even if you had all the materials, manufacture of a working device is an incredibly difficult project. The equipment required is enormously expensive and complex. Were you to attempt to buy it outright, or certain components, you would quickly draw the undivided attention of people you really don't want to meet. Few countries, much less individuals, have the necessary technical resources and abilities.

 

[radagast]

Regarding the suitcase bomb, based on a simple U235 "gun" design:

While the U235 has a fairly long HL, these bombs required a trigger - a source of neutrons to trigger the chain reaction cascade. This is usually provided by a small about of Tritium *.

Tritium's HL is fairly short, and generally require changing within five to ten years.

* [a small, very delicate hollow sphere of gold, housing a source of tritium is placed so that the colliding subcritical portions of U235 heats the small amount of tritium sufficiently to cause a small amount of fusion. Not much from an 'explosives' perspective, but enough to produce plenty of neutrons]

 

[pervect]

Even if you had all the materials, manufacture of a working device is an incredibly difficult project. The equipment required is enormously expensive and complex. Were you to attempt to buy it outright, or certain components, you would quickly draw the undivided attention of people you really don't want to meet. Few countries, much less individuals, have the necessary technical resources and abilities.

I'm not convinced it's necessarily all that complex. I do think that to be confident of success, a certain amount of testing would be needed. This would imply being at a minimum able to acquire and routinely blow up high explosives if one is pursuing an implosion design, for instance - an activity which would seem to draw a fair amount of attention if attempted by an individual in any civilized area. There's a lot of desolate and uncivilized real-estate in the world, though, so it's not impossible.

 

[Blissfulpain]

what about a neutron bomb? to my limmited understanding, they are just part of the norml Nuclear bomb... i haven't looked into this stuff in a long time, so I'm working from memory. wouldn't a netron bomb be easier to build and less difficult to construct?

 

[selfAdjoint]

Actually they are trickier, because you have to reduce the blast while keeping the radiation. A dirty bomb would have a similar effect much more easily.

 

[LURCH]

Regarding the suitcase bomb, based on a simple U235 "gun" design:

While the U235 has a fairly long HL, these bombs required a trigger - a source of neutrons to trigger the chain reaction cascade. This is usually provided by a small about of Tritium *.

Tritium's HL is fairly short, and generally require changing within five to ten years.

* [a small, very delicate hollow sphere of gold, housing a source of tritium is placed so that the colliding subcritical portions of U235 heats the small amount of tritium sufficiently to cause a small amount of fusion. Not much from an 'explosives' perspective, but enough to produce plenty of neutrons]

I think that most weapons now use Lithium (which is not all that hard to get hold of) to produce tritium actually during the fusion process, don't they?

 

[Jenab]

First off, building a nuke is not difficult, its getting the materials needed to build it that is near to impossible without arrousing a response from intelligence agencies. U-235 is needed, and can only be obtained by milling the more common U-238. Milling involves a process that requires several football fields worth of space and extremely expensive equipment.

The uranium can be chemically separated from the rock. Are you referring to gas diffusion separation of the isotopes? I understand that a much more compact method involves lasers that ionize gaseous U235 and U238 at differential rates, permitting them to be separated by magnetic field.

Of course, you could get U-235 from nuclear facilities, but most of it would be impurely mixed with U-238. To start the runaway effect know as fission, the U-235 must be at least 97% pure, which no nuclear facility produces at that weapons grade purity.

U235 makes a nice neutron source for transmuting U238 into fissile Pl239, which is somewhat better for bombs than U235 is.

Secondly, there are dozens of other elements needed to attain fission, like cadmium (heavily regulated), Plutonium (heavily regulated), and many others. Also, without extremely in depth blueprints, or technical know-how, you would never get the U-235 to properly implode. Also, its the last 2 or 3 fissions that create the huge mushroom cloud, and they are the most difficult to achieve.

Not true. It's hydrogen fusion that has the microsecond collapse requirement. A fission bomb's critical core can assemble in a more leisurely time, a millisecond maybe. A pair of cannons shooting purified 2/3 critical mass U235 cannonballs at each other with gunpowder as the propellant can get the job done. Usually, the assembly is carried out with the detonation of 20 dodecahedrally emplaced charges of RDX or PETN on a hollow sphere of tamper material - which might be U238 - which collapses supersonically on a fissile core, which compresses the core metal to a supercritical density.

The stories about homemade fusion bombs are probably fiction, though. The design of the h-bomb cavity is intended to reflect the radiation from a fusion bomb trigger in way that focuses several hundred microseconds' worth of radiation into a single microsecond impingement on the tritium containing vessel (which might be lithium hydride). The fusion needs to proceed in a snappier manner than the fission trigger would ordinarily supply energy, so the bomb makers interpose a U238 shield between the fission and fusion parts of the h-bomb, so that the gamma rays taking the straight route will be slowed down by the dense material.

Jerry Abbott

 

[TheStatutoryApe]

So then what about a dirty nuke? I've heard that they are very definite possibility and far easier to create/obtain. There are only two problems I can think of with these aside from the obvious difficulty of obtaining the radioactive materials. 1) I don't know whether or not spreading the low grade radioactive material in such a manner would have that strong an effect. Maybe just exposing people to several rads more than what they would normally come in contact with and increasing their risk of cancer dramaticly unless they happen to be in close proximity to the explosion at the time of the explosion. 2) Moving about a significant enough quantity of radioactive material to use in such a bomb without it being detected. This last one seems to me probably the biggest challenge once the materials are obtained, perhaps even more so than obtaining the materials.

 

[Morbius]

The college student (he was actually a physics grad student) was hired by the government to try to design a nuclear bomb. He succeeded, as you said working off his own physics knowledge and open published material. (Actually there were two students, the first one got a good start but had to go back to school, the second one made the successful design).

The design was evaluated by experts, and they agreed it would have worked. Of course it was never built.

WRONG WRONG WRONG

No "expert" every said anything of the sort. [ Maybe some self-styled "experts"]

See the following about DOE's policy in this regard:

http://www.inel.gov/inews/2000/06-06-00/0606nocomment.htm

You can read the publically released verion of the "N-th Country
Experiment" at:

http://www.thebulletin.org/issues/2003/ma03/ma03stober_doc.html

http://www.gwu.edu/~nsarchiv/news/20030701/nth-country.pdf

You can see that the conclusions as to how well the participants did
have been deleted from the published report.

Dr. Gregory Greenman
Physicist

 

[RonRyan85]

One last opinion poll for all of you that responded to my question
about "Home made H-Bombs". I read about and have heard on late night
radio programs about the possible existence of "SUITCASE NUCLEAR
BOMBS" being purchased from the old CCCP KGB and about 20 are already
hidden here in the USA. (See article located here at: http://nuclearweaponarchive.org/News/Lebedbomb.html)Some say it's
possible and others say the old bombs (small artillery shell nukes)
would not work unless persons with the knowhow have added new battery
power and a new Tritium or Lithium triggering device. What do you
guys think?

 

[MedicalPhysics]

Why is this issue even worth discussing? It is impossible for any small group (terrorists or not) to get their hands on the high level materials that can ONLY be found in power plants, and are more than well secured. I've worked extensively in cross-training with power plants in emergency drills and triage activity exercises and planning. Not even crashing a plane into a power plant in this country would result in external contamination of sources. The problem with nuclear terrorism exists because of the incredible amount of ignorance in the general public and media. I would be much more concerned about biological or toxicological terrorism rather than nuclear terrorism. The less secure sources are all low level sources and would do more damage from the explosion and fear and chaos in the public, than from radiobiological impacts. I mean, geez, think about it; what is someone going to do, make a bomb with a maximum of 100 millicuries of Tritium, C-14, S-35, P-32, Rb-86, I-125, I-131, Tc-99m, P-33, etc. ? Use your head people. The only scary thing about that is how the media and public would react just from hearing the word "radioactive" or "isotope". Nuclear technology has always been misunderstood in the public, due to ONE country's ignorance and lack of common sense on how to use the technology. Who has the only record of using nuclear technology to destroy? The United States. Yes, if a new technology evolves and the U.S. uses it in war for the purpose of destruction; sure, it will also get a bad reputation from its inception. Common sense goes a long way in this world, and sometimes ignorance can spread like a disease when common sense fails to be used.

 

[selfAdjoint]

MedicalPhysics, your objections are valid for the idea of diverting domestic radioactive materials for a bomb; the idea of doing this is pretty much just an urban legend. But the possibility of some terrorist group obtaining weapons grade nucleides or even assembled bombs through some black market abroad is not so outlandish. The Bush administrtion has shown no interest in trying to prevent theft of materials from the former USSR sites that are now in poor countries.

 

[Pengwuino]

MedicalPhysics, your objections are valid for the idea of diverting domestic radioactive materials for a bomb; the idea of doing this is pretty much just an urban legend. But the possibility of some terrorist group obtaining weapons grade nucleides or even assembled bombs through some black market abroad is not so outlandish. The Bush administrtion has shown no interest in trying to prevent theft of materials from the former USSR sites that are now in poor countries.

I thought they had a program 3 years ago going up for review and approval by the Russians that would have doubled funding to securing the materials. It was part of an anti-terrorism bill on our side and I have on reason to think it didn't get passed here since it was part of a pretty big bill.

 

[Pengwuino]

due to ONE country's ignorance and lack of common sense on how to use the technology. Who has the only record of using nuclear technology to destroy? The United States. Yes, if a new technology evolves and the U.S. uses it in war for the purpose of destruction; sure, it will also get a bad reputation from its inception. Common sense goes a long way in this world, and sometimes ignorance can spread like a disease when common sense fails to be used.

One country? Your saying every other country on Earth's population knows far more then teh average American when it comes to nuclear technology? And what does someone using it have anything to do withs perceived danger? Let's say we didn't use it. Do you really think peopel would have seen footage of tests by the US and Russia and France and China and every other nuclear nation that whiped out islands or tore through mothballed battleships or anything like that and simply thought "Oh well, that's not a bad weapon! i like it!". Sounds like the latter idea is showing more ignorance then what you think is the ignorance in the public.