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Inertially Confined Catalyzed Fusion

What a difference a heavy negative charge might make!
  [vote for,

Ordinary "ICF", Inertially Confined Fusion, starts with a small pellet of frozen-solid deuterium, or a mixture of deuterium and tritium, and zaps the pellet from all directions with high-energy laser beams or electron beams. The energy that arrives causes the outer layers of the pellet to explode outward. The Law of Action and Reaction causes the rest of the pellet to implode to a very tiny size, also very very hot. Fusions can occur at that temperature and pressure. The goal is to get enough energy from those fusions to be able to "pay" for the initial energy blast (and extra to sell, of course).

For a number of years (and I've written about this elsewhere, but not as its own Idea), I've wondered about the effect of injecting a muon into the ICF environment. A muon is a subatomic particle that has many properties very similar to the electron, it's biggest difference is that it is about 206 times as massive as an electron. It is also an unstable particle that typically only lasts for about 2 microseconds (this is actually a decent amount of time in the subatomic realm, as you will see).

It is known that in liquid deuterium-hydrogen (very cold!) an injected muon can catalyze nuclear fusion reactions. It does this in several steps. First it replaces the electron that normally orbits one deuterium atom. Because it is 206 times as massive as the electron, it orbits 206 times closer, making a "muonic" atom that is 1/206 the normal size. Ordinary thermal motion can cause this atom to collide with a nearby atom --but because it is 1/206 the size, it is "denser" than the other atom, and can plow right through the electron shell, instead of bouncing off the way a normal atom would. INSIDE the ordinary atom, the muon is electrically attracted to that atom's nucleus, and sort-of drags the nucleus it is orbiting, along with it. When the two nuclei get close enough, they fuse, and some of the energy of the reaction can cause the muon to be kicked out, away from the site of the reaction.

I've known for years that the muon can live long enough to catalyze another fusion reaction in the same way. I've also known that the total number it can fuse, before it dies, does not release enough total energy to "pay" for manufacturing the muon (at least partly because of inefficiencies in the processes that can yield muons). This was figured out in the 1950s not long after the process of "muon catalyzed fusion" was first discovered.

What I did not know until today was just how many fusions the muon could catalyze before it died. "Not enough" is not a number, after all! Would you believe the answer is, "Up to 170"? (See what I mean about 2 micoseconds being a significant amount of time!) The answer is not always 170 because sometimes the muon does not acquire QUITE enough energy from the reaction to escape, so it stays in orbit, basically useless, until it dies. Not to mention that even when I didn't know that "not enough" number, I did happen to know that however-many fusions it was, it was not enough by a factor of 5 or 6, to be able to produce enough energy to pay for making the muon. So, we need a muon to cause something like 170*5=850 or 170*6=1020 fusions (I'll call it nine hundred, because we want EVERY muon to do that), if possible.

Anyway, I've speculated for years about what would happen if a muon was injected into the middle of an imploding pellet, in an ICF experiment. The muon would not necessarily go into orbit because at a certain point of the implosion, the matter of the pellet has converted from frozen solid to hot plasma (totally ionized matter).

On the other hand, the energetics of a muon-orbit are over 40,000 times the energetics of an electron-orbit, thanks to the Inverse Square Law (orbiting 206 times closer than normal means the electrical attraction is 206x206 normal). So at least during part of an ICF implosion, the muon could still get into orbit to do its catalyzing thing perfectly normally, and in fact more easily than in liquid deuterium, because during the implosion all the nuclei of all the atoms are closer together than in liquid deuterium.

Here is the key Question to this idea: How Much Closer Are Those Nuclei In An ICF Experiment??? Note that if we assume a muon can travel some total distance X in its lifetime, and if in liquid deuterium it can encounter and orbit 170 atomic nuclei, and encounter and fuse those nuclei with 170 more atomic nuclei, then that means the average distance between nuclei must be something like X/340, in liquid deuterium.

Doesn't it logically figure that if the distance between nuclei was squeezed down to 1/6 the normal distance, in an ICF experiment, then there would be 6*340=2040 nuclei for the muon to encounter in the distance it could travel during its lifetime? That would be 1020 fusions, certainly more than the 900 mentioned as desired above.

Folks, the fact is, in ICF experiments, nuclei are routinely squeezed down to something like 1/50 their normal separation distance! That means just one muon could catalyze up to 50x170=8500 fusions! That should be enough to not only pay for the muon, but also to pay for a significant chunk of the blast of energy that caused the implosion. Add a few more muons and all of that energy blast could be paid for. Add a few more muons, and now we are in the nuclear fusion power-plant business!

Vernon, May 07 2009

An old fusion Idea I posted Three_20Fusion_20Reactor_20Variations
Search the annotations for "muon"; it clearly shows I've been thinking about this independently of the item in the next link. [Vernon, May 07 2009]

Some muon-catalyzed fusion data http://scitation.ai...type=cvips&gifs=yes
As mentioned in the main text [Vernon, May 07 2009]

Muons aren't the only possible catalyst http://www.springer...t/6658672700g6133t/
Now, if the implosion was VERY hot, so that antiprotons did not go into orbit, how many fusions could they catalyze? [Vernon, May 07 2009]

Metallic Hydrogen Inertial Confinement Metallic_20Fusion
I hinted here using muons to further fuse the metallic atomic nuclei subjected to high implosion pressures [rotary, May 07 2009]

Anomalous regeneration of muon from possible ionization of (ma)+ http://www.iaea.org...2000/pdf/icp_15.pdf
By increasing the temperature, the anomaly increases. Maybe your suggestion of higher pressure due to implosion would lead to much higher anomaly--leading towards above break-even. [rotary, May 09 2009]


       Well, yes, seems not unreasonable. One question (and this may be very naive). You're assuming that the number of fusions a muon can catalyse is limited only by the number of nuclei it can traverse in its lifetime; this in turn assumes that they spend no time during each fusion. Is this so? And is there no way to just make muons move faster, rather than putting the nuclei closer together?
MaxwellBuchanan, May 07 2009

       [Maxwell Buchanan]], a muon will stop moving faster as soon as it goes into orbit. It will have to give off that energy getting into orbit. And of course the speed it moves at, between fusions, depends solely on the energy it acquires from the fusions it catalyzes. There's no obvious way to enhance that at all. So, reducing the distance between nuclei is the best way.   

       Now, IF a muon can catalyze a fusion while NOT going into orbit, say by passing between two almost-collided deuteriums, then in that case the faster the muon moves, the more fusions it might catalyze. But there is enough uncertainty about that to not want to recommend it out-of-hand. The faster the muon moves, the less time it spends between the deuterons, interfering with their mutual electric repulsion. In orbit we KNOW it can interfere long enough for the deuterons to fuse. Outside of an orbit we don't know that, at all.   

       So, logically, we want to compress the deuterium fuel pellet without heating it up so much that muons cannot get into orbit, when implementing this Idea. There is certainly a limit (the more the squeeze, the higher the temperature); I just don't know at this time how that limit compares to the distance between nuclei. For example, it is possible that a 50-fold squeeze will result in rather too-high a temperature, for a muon to get into orbit, to do its catalysis thing.
Vernon, May 07 2009

       OK. But there's still the question: what proportion of their time do the muons spend a-movin? If it's only 10%, then closening up the nuclei won't give a significant increase in the number of fusions catalysed.
MaxwellBuchanan, May 07 2009

       That is a valid question (possibly improved by asking how much time does a muon spend in orbit before the muonic atom approaches another atom's nucleus), and it could certainly mean that we have to squeeze more than 6 times to get a 6-fold increase in the number of catalyzed fusions. To Be Determined by experiment, of course!
Vernon, May 07 2009

       [Vernon], I do hope you have time to study if my proposed solution to improve the efficiency of muon production is viable. My solution is described under one of the ideas of [xkuntay] - Metallic Fusion (see link). If muon production is vastly improved, then you might probably need only half of your intended moun reactions to make fusion above break-even point.
rotary, May 07 2009

       [rotary], there are recent real developments in particle accelerators that might meet the need. I think the technique is called "plasma wave" acceleration, or something like that. The most efficient way to make muons that I'm aware of is to collide electrons and positrons at a "resonant" energy of rougly 210MeV.   

       Of course the positrons have to be made before you can accelerate them to collide them with accelerated electrons, but it only takes a little more than 1Mev to create a positron/electron pair, and I'm pretty sure the particle-accelerator physicists have worked out reasonably efficient ways to do that, since they have used so many positrons in such long-term experimental facilities as the Large Electron Positron Collider.   

       There is also a minor efficiency thing here: once you create an electron and a positron, and collide them to make a muon and an anti-muon, only the muon is needed for fusion catalysis (and it should be immediately injected into the reactor). Meanwhile, the anti-muon will decay in about 2 microseconds, and one of its decay products is a positron. Obviously that positron can be re-used to make another muon/anti-muon pair.
Vernon, May 08 2009

       Well hello again guys! I heard my favorite subject is being discussed again so I came right over. I must say I am glad to see there are still unique ideas to explore on fusion! Now cutting the phony talk short and going back to the idea, I will give you a [+] for this one Vernon. A sound and agreeable combination of ICF and catalyzed fusion.. but not without reservation! My first and foremost question is: how do you inject the Muons in there without intercepting with the lasers? And then there are bunch of more theoretical and practical concerns that can be posed. But all in all, for HB purposes, it goes on the tray and into the oven with lot of butter.
xkuntay, May 09 2009

       Inertially confused.
MaxwellBuchanan, May 09 2009

       Inertially infused.
wjt, May 10 2009

       Defiladedly amalgamused
reensure, May 10 2009

       [xkuntay], it is easy to get the muons through the laser blast, because of a necessity. The necessity relates to the 2-microsecond lifespan of a muon; it can't travel very far in that time UNLESS it is moving at nearly the speed of light. Then Relativity will do its time-dilation thing and significantly enhance the perceived lifespan of the particle.   

       So, it is necessary to manufacture the muon in such a way that it is moving at nearly the speed of light. This can be done if the electron and the position are also moving at nearly light-speed, in roughly the same direction, but ALSO are converging at a rate such that their collision has the "resonant" energy that I mentioned in another anno.   

       Once you have a muon moving at nearly light-speed, a mere laser blast won't keep it from zooming into the imploding fuel pellet.
Vernon, May 11 2009

       I'm confused. the Abstract in the second link tells about using muon-catalysts in the context of inertially confined fusion - is your idea to simply whack the pellet with lasers, additionally?
loonquawl, May 11 2009

       /is your idea to simply whack the pellet with lasers, additionally/   

       If this is all it boils down to, of course I'm for it!
bungston, May 11 2009

       [loomquawl], ICF is typically initiated by either a laser blast or an electron blast (energetically, I think the electron blast is more efficient). The muons described here should be made/injected almost immediately after that blast has started the pellet-implosion process.
Vernon, May 11 2009

       [Vernon] would be pleased to note that a lot of what he says, so far as cold fusion goes, has been taking place.   

       Further, the 'inertia contained, Gravity sling-shot' he describes here is being seriously considered as a contributor to Dark matter/ Dark energy perterbations that we see on a grander scale.
4whom, May 12 2009


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