Fourth Generation Nuclear Weapons

[Astronuc]

Muon-catalyzed fusion is an example of controlled thermonuclear reaction which is not the intent of nuclear weapons. As vanesch pointed out, it would not be feasible to introduce a muon source/generator within a nuclear weapon system. It might be worthwhile to split it off this discussion into a separate thread.

The buckeye ball idea is interesting but it faces some significant drawbacks. It seems suitable perhaps to the Inertial Confinement Systems, which already use cryogenic pellets, but then there is the matter of getting D-T or D-D into the buckeyeballs. One has to look at the conditions in which buckeyeballs are produced and compare that to solid/metallic hydrogen. Metallic hydrogen is formed under high compressive pressures.

A high-pressure phase of atomic hydrogen predicted theoretically to form at the center of Jupiter, was first produced in the laboratory by Weir et al. (1996), at a pressure of 93-180 GPa and temperature of 2200-400 K.

http://scienceworld.wolfram.com/physics/LiquidMetallicHydrogen.html

Liquid metallic hydrogen and the structure of brown dwarfs and giant planets
http://arxiv.org/abs/astro-ph/9703007

http://www.ncsa.uiuc.edu/News/Access/Stories/MetalHydrogen/Hydrogen.html

Are the process of buckeye ball formation and filling with hydrogen molecules compatible? What is the energy input and cost?

OK - assuming one obtains a collection of (DT)/(DD) buckeyeballs, how does one utilize them for fusion production? ICF? A beam of muons?

A unidirection beam of muons is problematic, to say the least, largely because of their very short lifetime.

The other factor is once some buckeyeballs experience fusion - the fusion plasma will blow them apart and collection/mass of buckeyeballs and the buckeyeballs themselves disperse.

 

[sanman]

Hi Astronuc, thanks for your response.

Well, note that the buckyball would contain mere hundreds of hydrogen atoms. How much energy could the fusion of these mere hundreds of atoms release, that they would not just blow apart but also disperse the surrounding buckyballs, before allowing other fusions to occur?

If these fusions are taking place among multiple buckyballs in a vicinity, then some will be dispersing buckyballs away, while others will see buckyballs dispersed towards them.

I'd imagine that the energy released by a fusion could help to cause adjacent atoms to fuse.

I'm not sure how fusion energy output is measured in muon-catalyzed fusion experiments. Is it measured in the form of a temperature rise in the frozen hydrogen medium? Or just in the form of gamma-ray and neutron-counter measurements?

 

[Astronuc]

Fusion reactions like the d+t reaction would be measured by the 14.1 MeV neutron.

http://en.wikipedia.org/wiki/Fullerene#Buckyballs - indicates the diameter from nucleus to nucleus of C₆₀ is about 0.7 nm or 7 Å. How much DT or DD could one put in a C₆₀ buckyball. I'm not sure this would be practical

It might be interesting to try boron bucky encasing H in order to try the p+B reaction. But I see this as an ICF target - perhaps, and not for magnetic confinement.

 

[James Essig]

Hi Sanman and Astronuc;

This has been an active and informative thread over the past day or so. Even if some of the ideas I have expressed over the past few days don't seem to hold water and turn out to be nonesense, I have still enjoyed the discussion.

Anything that advances the state of fusion physics or applied nuclear physics is cool to me. The National Ignition Facility should give us plenty of experimental data in nuclear fusion science and the interaction of particles within compressed plasma at temperatures on the order of 10 million K to 100 million K.

Thanks;

Jim

 

[sanman]

boron buckyballs, p+B

Fusion reactions like the d+t reaction would be measured by the 14.1 MeV neutron.

http://en.wikipedia.org/wiki/Fullerene#Buckyballs - indicates the diameter from nucleus to nucleus of C₆₀ is about 0.7 nm or 7 Å. How much DT or DD could one put in a C₆₀ buckyball. I'm not sure this would be practical

It might be interesting to try boron bucky encasing H in order to try the p+B reaction. But I see this as an ICF target - perhaps, and not for magnetic confinement.

Thanks for your response, Astronuc. It certainly gave me food for thought.

I still think that compression to metallic state would permit some slightly more rapid D-μ-T formation, which would benefit the muon-catalytic process. It still merits investigation even just for academic purposes.

But what you said about Boron buckyballs (B80) for the same type of setup, sounds very interesting. One might even suggest a Boron Nitride buckyball (B60N60, aka 'fulborene').

http://www.sciencedaily.com/releases/2007/04/070423111604.htm
http://www.mext.go.jp/english/news/1998/12/981206.htm
http://scitation.aip.org/getabs/servlet/GetabsServlet?prog=normal&id=APPLAB000075000001000061000001&idtype=cvips&gifs=yes

So based on what you've said, if any fusion energy produced inside the buckyball causes H to hit B with enough energy, then we get to benefit from the H+B fusion reaction as well, which however generates substantially lower power, but at least further exploits the encapsulating cage molecule:

http://en.wikipedia.org/wiki/Aneutronic_fusion#Technical_challenges

While the H+B fusion reaction is substantially lower in energy yield, perhaps this might be beneficial in terms of making the power release more manageable (ie. not dispersing all the surrounding buckyballs). It is also an aneutronic reaction, which could perhaps reduce the hazard of neutron radiation. Likewise, if the encapsulated atoms were all H instead of D & T, then H+H fusion reaction while producing 40 times less energy might similarly make the energy release more manageable and less catastrophic. Furthermore, is it possible that the positrons produced from the muon-catalyzed H+H fusion would anihilate with local H-bound electrons, thus increasing the opportunities for more rapid H-μ-H formation?

I am not sure what the cage strength of the B80 buckyball is, but fulborenes like B60N60 are supposed to have comparable strength to their carbon fullerene counterparts. Apparently the B-N bond is supposed to have a polar character which aids its strength when networked.

 

[vanesch]

Muon-catalyzed fusion is an example of controlled thermonuclear reaction which is not the intent of nuclear weapons. As vanesch pointed out, it would not be feasible to introduce a muon source/generator within a nuclear weapon system. It might be worthwhile to split it off.

Haha , using the SFSDS (Super Fast Strategic Delivery System) (TM). You initiate the detonation with a ground-based muon-source, and then you have 2 microseconds left to launch and deliver

 

[Astronuc]

I still think that compression to metallic state would permit some slightly more rapid D-μ-T formation, which would benefit the muon-catalytic process. It still merits investigation even just for academic purposes.

It would make for some interesting research.

But what you said about Boron buckyballs (B80) for the same type of setup, sounds very interesting. One might even suggest a Boron Nitride buckyball (B60N60, aka 'fulborene').

The drawback to BN is that the N competes with B for the p's.

So based on what you've said, if any fusion energy produced inside the buckyball causes H to hit B with enough energy, then we get to benefit from the H+B fusion reaction as well, which however generates substantially lower power, but at least further exploits the encapsulating cage molecule:

http://en.wikipedia.org/wiki/Aneutronic_fusion#Technical_challenges

I was musing about the p+¹¹B aneutronic reaction. If possible, aneutronic reactions are preferable with respect to direct energy conversion. The d+t fusion reaction is the easiest one to achieve, but one looses about 80% of the energy to the neutron, which then must be collected and the thermal energy extracted by more traditional means, as opposed to direct energy conversion. It also reduces or eliminates activation of the plasma containment structure.

Li+D (D + ⁶Li → 2 ⁴He + 22.4 MeV ) is an attractive fusion reaction from the energy/alpha particle and no neutrons.

While the H+B fusion reaction is substantially lower in energy yield, perhaps this might be beneficial in terms of making the power release more manageable (ie. not dispersing all the surrounding buckyballs). It is also an aneutronic reaction, which could perhaps reduce the hazard of neutron radiation. Likewise, if the encapsulated atoms were all H instead of D & T, then H+H fusion reaction while producing 40 times less energy might similarly make the energy release more manageable and less catastrophic. Furthermore, is it possible that the positrons produced from the muon-catalyzed H+H fusion would anihilate with local H-bound electrons, thus increasing the opportunities for more rapid H-μ-H formation?

p+p is not very efficient. That's the reaction that fuels the sun, and there the p-density is comparable to water at room temperature. The problem with fusion in metallic hydrogen is that as soon as fusion occurs, the metallic hydrogen heats and is no longer metallic hydrogen.

I'm not sure that positron annihilation occurs rapidly enough, nor frequently enough, to have a significant impact.

I am not sure what the cage strength of the B80 buckyball is, but fulborenes like B60N60 are supposed to have comparable strength to their carbon fullerene counterparts. Apparently the B-N bond is supposed to have a polar character which aids its strength when networked.

B80 research is still in its infancy - http://www.eurekalert.org/pub_releases/2007-04/ru-bbt042307.php

Haha , using the SFSDS (Super Fast Strategic Delivery System) (TM). You initiate the detonation with a ground-based muon-source, and then you have 2 microseconds left to launch and deliver

Would that be a 10¹⁵TW source?

 

[sanman]

It would make for some interesting research.

The drawback to BN is that the N competes with B for the p's.

I was musing about the p+¹¹B aneutronic reaction. If possible, aneutronic reactions are preferable with respect to direct energy conversion. The d+t fusion reaction is the easiest one to achieve, but one looses about 80% of the energy to the neutron, which then must be collected and the thermal energy extracted by more traditional means, as opposed to direct energy conversion. It also reduces or eliminates activation of the plasma containment structure.

Li+D (D + ⁶Li → 2 ⁴He + 22.4 MeV ) is an attractive fusion reaction from the energy/alpha particle and no neutrons.

What about a lithium-coated buckyball (Li12C60) then?

http://www.primidi.com/2006/07/26.html
http://www.greencarcongress.com/2006/07/researchers_des.html

I don't know what its cage strength is, though. Hopefully it would be comparable to C60.
They do mention it could store 13 Wt% of Hydrogen, but these appear to be H-bonded to the outside of the Li12C60 buckyball. Maybe these could supplement storage of hydrogen inside the buckyball as well.

So you could fire your muons at the Li12C60 buckyball, and if it catalyzed any fusions among the encapsulated D, then energy could be imparted to nearby D which might perhaps collide with the Li in the surrounding shell.

I've never heard of muon-catalyzed fusion being attempted with non-hydrogen reactants.
Could it work for Li+D directly? Could you just stuff LiD inside the buckyball and try to catalyze fusion on that?

B80 research is still in its infancy - http://www.eurekalert.org/pub_releases/2007-04/ru-bbt042307.php

Well, if you look at the structures of the B80 and Li12C60 buckyballs, then is there any way to make a buckyball out of Li and B?

 

[sanman]

Hmm, found this:

http://www.iop.org/EJ/abstract/0954-3899/16/2/017

http://www.iop.org/EJ/abstract/0954-3899/16/2/017"

D Harley et al 1990 J. Phys. G: Nucl. Part. Phys. 16 281-294

D Harley, B Muller and J Rafelski
Dept. of Phys., Arizona Univ., Tucson, AZ, USA

Abstract. The authors investigate the processes involved in muon catalysis of hydrogen isotopes with light nuclei Z>1, with the objective of identifying systems in which at least one fusion per muon is possible. They systematically explore all nuclear systems and identify those having the potential to lead to fast fusion rates despite the high Coulomb barrier. They consider in some detail the tunnelling through this barrier as well as the internal conversion of the muon. Furthermore they establish, in qualitative terms, the necessary conditions for muomolecular rates in collisions of muonic atoms of hydrogen isotopes with small concentrations of light elements.

Print publication: Issue 2 (February 1990)

 

[sanman]

p+p is not very efficient. That's the reaction that fuels the sun, and there the p-density is comparable to water at room temperature. The problem with fusion in metallic hydrogen is that as soon as fusion occurs, the metallic hydrogen heats and is no longer metallic hydrogen.

Yes, but if p+p releases enough energy to cause nearby p to collide with B80 shell, then you could get multiple p+B fusions as well, even if the B80 blows apart.

Here is something I found relating to this problem of fusion energy release vs. sustainability of the reaction process:

http://www.informaworld.com/smpp/content~content=a739286799~db=phys~order=page

http://www.informaworld.com/smpp/content~content=a739286799~db=phys~order=page"

Negative muons may be used as a catalyst to fuse hydrogen nuclei into helium. The necessary confinement of nuclei is obtained on a microscopic scale by chemical bonding within 'exotic' muonic molecules such as dtμ, without the extreme physical conditions required for macroscopic plasma confinement in Tokamaks and laser reactors. Fusion energy released by muon catalysis exceeds the rest-mass energy of participating muons, which triggered questions about suitability of this process for energy production. The present article reviews the theoretical studies of the microscopic events constituting the fusion chain. The aim of these studies is to optimize the fusion yield by understanding its dependence on the macroscopic conditions such as temperature, fuel density and/or composition. Apart from the energy production aspects, the field of muon catalysed fusion (μCF) is also a wonderful example of interdisciplinary basic research combining exotic chemistry with atomic, nuclear, and particle physics. While the μCF reactions occur for all hydrogen isotopes, the present review emphasizes the theoretical and experimental results obtained for the case of dtμ.

 

[sanman]

Muon Catalysis of p-Z Fusion Reactions at Z>1

http://www.jetpletters.ac.ru/ps/1254/article_18967.pdf

Ahh, I see. The higher the charge of the reaction products, then the more likely the muon will stick to those products (eg. "alpha-sticking")

But doesn't that then recommend H + H -> D + positron + neutrino
Because then at least the D product has a minimal charge to minimize muon-sticking

 

[James Essig]

Hi sanman;

A couple of weeks ago, I read an article in a very recent issue of Science News Magazine about the concept of so-called super atoms. These are arrangements of individual atoms within relatively large molecules wherein the molecules have orbitals as a whole in much the same way that a single atoms has electron orbitals or electron cloud/shells.

The article stated that perhaps certain forms of super atoms could store dense states of hydrogen within a central cage like section. If these super atoms can store H1, then I suppose they could store dense forms of deuterium and perhaps even dense forms of tritium.

I am not sure how this would benefit the subject methods discussed above for muon catalyzed fusion, but perhaps it could be of benefit. I do not know if superatoms could store hydrogen, and the like in denser form than fullerenes or nested fullerenes, but since you have expressed interest in the above subject, I thought I would pass this information along in case you have not already heard of super atoms for such potential applications.

Regards;

Jim

 

[sanman]

Hi James,

Here's what I read on the Superatom:

http://en.wikipedia.org/wiki/Superatom

 

[James Essig]

Hi sanman;

Thanks for posting the Wikipedia link to the superatoms article. I found the article most interesting.

By the way, the Science News issue I was referring to is either the latest issue or the previous one. The article is of good quality and is about 3-4 pages long.

I support any thing that has clean nuclear energy for commercial electric power production given the threat of global warming and the resulting threat to our national security and even global security. Nuclear fusion would be great for such a purpose.

I guess if the nuclear genie must remain out of the bottle, then we might as well if possible develope pure nuclear fusion devices and hopefully upon successful development of such devices, replace our current stockpile with pure fusion bombs which I would assume could be made in multiple megaton yield versions and thus not just in low yield versions such as 0.1 to 1.0 kiloton yeild devices.

Regards;

Jim

 

[sanman]

Here's another new article, James:

http://www.physorg.com/news134129791.html

I'm wondering how this phenomenon could be studied in more detail, rather than making blackbox macroscopic measurements? Maybe attosecond lasers, etc, could help to image these "superatoms" to tell us in more detail what's going on.

Are these superatoms a basic/primitive version of a Bose-Einstein Condensate?

 

[James Essig]

Hi sanman;

Thanks for the URL to the article. I plan on reading that article in full later this evening.

It occurred to me that indeed, attosecond laser pulses might be good to study superatoms. Other methods might include x ray diffraction crystallography, neutron diffraction crystallography, electron microscopy, or any other techniques capable of resolution on the scale of say 0.05 nanometers to 5 nanometers.

From what I gather from what I have read so far on the subject, it seems that the electronic clouds or socalled called orbitals of these superatoms seem to follow the same rules of magic numbers for single atoms in filling the energy levels or shells.

Perhaps there is an effect simmilar to Bose Einstein Condensation going on here. You have really got me interested in this subject. I will have to read more later tonight.

Regards;

Jim

 

[Vals509]

why is it that when we already have powerful nuclear weapons, research is going into making more ones. isn't this like digging your own grave?

 

[Morbius]

why is it that when we already have powerful nuclear weapons, research is going into making more ones. isn't this like digging your own grave?

Vals509,

Because nuclear weapons - like ANY machine - will age and deteriorate.

What do you think would happen to your car or an airliner if you just parked it and didn't
do any maintenance on it? Would you really want to fly on an airliner that had just been
sitting on the tarmac for 30 years without being flown or serviced by a mechanic?

The two things that a nuclear weapon has to do is to explode when it is commanded to;
and NOT explode when it is not commanded to under ANY other conditions. For example;
in 2007; a US Air Force B-52 mistakenly flew several nuclear weapons from North Dakota
to Louisiana. What if that aircraft had crashed? Even in a crash, you do NOT want the
nuclear weapons to explode as nuclear weapons. Suppose the safety features were
compromised due to age. You do NOT want to own nuclear weapons and then NEGLECT
them.

Contrary to popular belief; and the missives in the media; the ongoing research is NOT
about making nuclear weapons "bigger" or "more powerful". The military has better and
more accurate delivery systems - the yields of new nuclear weapons have been going DOWN
for decades. [ The actual total yield of the US arsenal actually peaked during the Kennedy
Administration ]

The number one goal of current research is to make nuclear weapons SAFER!

For example, the new Livermore design for the RRW features many new SAFETY
features:

http://nnsa.energy.gov/news/1145.htm

"Insensitive high explosives, which are far less susceptible to accidental detonation,
will be used in RRW to replace conventional high explosives."

Unfortunately, it appears that nobody in Washington is interested in SAFER nuclear weapons.

Some like California's Senator Dianne Feinsten say that if the US makes a new nuclear weapon,
it would send the "wrong message" to the other nuclear powers. The problem for Senator Feinstein's
argument is "that ship has already sailed". The USA is the ONLY nuclear weapons state that is
NOT modernizing its arsenal:

http://gsn.nti.org/gsn/nw_20081029_2822.php

"Currently, the United States is the only declared nuclear power that is neither modernizing its nuclear arsenal
nor has the capability to produce a new nuclear warhead," Gates told the audience yesterday.

Dr. Gregory Greenman
Physicist