Star Scientific: muon-catalyzed fusion

Point out news stories, on the net or in mainstream media, related to polywell fusion.

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dkfenger
Posts: 30
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Location: Victoria, BC

Post by dkfenger »

Joseph Chikva wrote:
dkfenger wrote:I think a lower bound on muon production in the 400MeV range seems reasonable.
Reasonable but impossible.
I do not think that word means what you think it means.

Below 140MeV is impossible. Below 400MeV would require interesting physics and/or impressive engineering, but isn't impossible. Unlikely, vanishingly improbable, but not actually impossible.

Just because the current method to produce muons costs 6GeV doesn't mean it can't be done better if you try. We're only talking about a single order of magnitude, here. It's not as if the beryllium smashing approach was designed for highly efficient muon production, either. It only has to be good enough to produce useful amounts of muons at a reasonable cost, it doesn't have a break-even point to aim for.
And why I should concider deuterium cycle?
50-100 D-D events produce about 200-400 MeV
Not more.
Because we won't just see D-D events. D-D results in Tritium or He3 (ignoring the extra H or n), then those react with more D. The latter reactions are:
* Very energetic (17.6 or 18.3 MeV)
* The ones that actually produce alphas, to carry off the muons.

The muon loss vector is called 'alpha sticking' for a reason.

Joseph Chikva
Posts: 2039
Joined: Sat Apr 02, 2011 4:30 am

Post by Joseph Chikva »

dkfenger wrote:Below 140MeV is impossible. Below 400MeV would require interesting physics and/or impressive engineering, but isn't impossible. Unlikely, vanishingly improbable, but not actually impossible.

Just because the current method to produce muons costs 6GeV doesn't mean it can't be done better if you try. We're only talking about a single order of magnitude, here. It's not as if the beryllium smashing approach was designed for highly efficient muon production, either. It only has to be good enough to produce useful amounts of muons at a reasonable cost, it doesn't have a break-even point to aim for.
Yes, below 140MeV impossible.
400MeV was calculated by taking into account effeciency of accelerator 35%. As:
140/0.35=400
So, this is minimum possible energy that should be spent per muon creation event admiting that process is 100% selective. That impossible as such.
As together with creation of pions there many other types of reactions will be observed.
dkfenger wrote:Because we won't just see D-D events. D-D results in Tritium or He3 (ignoring the extra H or n), then those react with more D. The latter reactions are:
* Very energetic (17.6 or 18.3 MeV)
* The ones that actually produce alphas, to carry off the muons.
I do not know about "alphas, to carry off the muons".
And can not imagine that. Know from two or three sources only about average fusion events providing by a single muon. And the number is 50-100. And not more.
Yes, D-T and D-He3 produce about 4.5 more energy per each event.
That is not an order of magnitude.
All the more He as such can not create meso-molecule and I am not sure in its ability to react in such a manner.

dkfenger
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Joined: Thu Jul 07, 2011 9:55 pm
Location: Victoria, BC

Post by dkfenger »

There's a 1998 overview linked from the Wikipedia page on muon catalyzed fusion that explains the 4-6GeV figure a bit better. This is not the value for any current facility, but the best theoretical case that various researchers had come up with. Most seem to involve accelerating deuterium or tritium at about 1GeV into deuterium-tritium targets, with a muon yield in the .17 to .25 range.

One study considered colliding counter-rotating beams of deuterium and suggested that a yield near .5 muons per collision was possible, but it would be fairly impractical to build.

I did find a few papers suggesting using high-intensity lasers to produce muons, but the yield was atrociously low.

Without some pretty serious breakthrough physics (which Star Scientific has shown no real evidence of), this seems like a dead end.

Still, there seems to be ongoing research, and suggestions that the sticking rate can be in the .35% range for proper conditions (tritium concentration seems to be a factor). Maybe one day...

Joseph Chikva
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Joined: Sat Apr 02, 2011 4:30 am

Post by Joseph Chikva »

dkfenger wrote:Without some pretty serious breakthrough physics (which Star Scientific has shown no real evidence of), this seems like a dead end.
But they have quite good web-designer and very good clip-maker. :)

Torulf2
Posts: 285
Joined: Fri Sep 21, 2007 9:50 pm
Location: Swedem

Post by Torulf2 »

Look that that man has done before.
http://www.couriermail.com.au/news/feat ... 1119160884

seedload
Posts: 1062
Joined: Fri Feb 08, 2008 8:16 pm

Post by seedload »

Torulf2 wrote:Look that that man has done before.
http://www.couriermail.com.au/news/feat ... 1119160884
Thanks, good find.

EDIT -

It wasn't different. It was the same. But the fiasco wasn't his doing. Gotta feel bad for the guy getting forced to come forward with his unfinished technology.

http://www.stephenhorvath.com.au/
By 1979, Stephen had developed and patented (No 7918107) the prototype for a car powered through fusion-enhanced hydrogen burn as part of his ongoing research into alternative fuel sources. When the then Queensland Premier, Sir Joh Bjelke-Petersen learned of the project, he invited Stephen to display his work publicly. Unfortunately, Sir Joh's foresight to bring about a pollution free hydrogen economy has not eventuated as yet.

As a result, an announcement was made which put Stephen in an awkward position, since he knew his work was incomplete and he had never wanted to promote the "hydrogen car" project as a finished product.

Nature is not very kind to inventors and entrepreneurs, not all of the innovative ideas have come to fruition - although each one has deepened Stephen's knowledge and understanding of his ultimate scientific goal - to unlock the secret to releasing energy via sustained muon-catalysed fusion.
Stick the thing in a tub of water! Sheesh!

D Tibbets
Posts: 2775
Joined: Thu Jun 26, 2008 6:52 am

Post by D Tibbets »

Joseph Chikva wrote:
dkfenger wrote:I think a lower bound on muon production in the 400MeV range seems reasonable.
Reasonable but impossible.
And why I should concider deuterium cycle?
50-100 D-D events produce about 200-400 MeV
Not more.
Actually, D-D reactions can produce more energy than the ~ 3 MeV per D-D fusion. I'm skeptical of the 40 MeV number, but still a lot more energy than 3 MeV. If you take 6 deuteriums, fuse 4 of them, you get one T, one He3 and ~ 6 MeV. Then fuse the last two D with the T and He3 and you get ~ 20 MeV and 12 MeV (estimates from memory). This adds up to ~ 38 MeV, but remember that this needs 4 separate fusion events to obtain. The average per fusion would be ~ 9-10 MeV/ fusion. Higher yields would come from burning D-T directly, but then you have to produce the tritium first.

Also note that the tritum and He3 would leave have to be moderated (slowed) befor reacting further (we are talking about liquid hydrogen temperatures). This would eat through the Muon aviable life time. If one muon could catalyze 100 reactions before it decayed, then it could at best catalyze 25 of the above chain reactions (100/4). This would dampen any advantage. One chain completed with ~ 35 to 40 MeV yield vs 4 D-D fusions with ~ 12 MeV. There is a possible advantage, but much less than was suggested, even without any time penalties that I suspect would be significant.

The reason liquid hydrogen temperatures are needed because high densities are needed to get usefull fusion rates with the short lived muons.
I supose you could approach this with a super DPF machine if you could synchronize everything, though the pinch (high density) only lasts for a fraction of a microsecond. Though with the time necessary for the creation and transfer of the muons, this time may be reasonable. But if it takes a significant fraction of the muons lifetime to get into place in the fusion reaction space, the possible number of fusions per muon goes down.

Creating muons in a particle accelerator can and has been done. But we are talking about a few . Perhaps a few dozen or a few million muons per second may be produced in the accelerator.

To produce ~ 1 MW, you need ~ 10^18 fusions per second . This divided by 100 fusions per muon means you would need ~ 10^16 surviving muons per second output from the particle accelerator. This would probably require a CERN on steroids accelerator*. That is why I said the total system size would even put ITER to shame. If there is some possibility of success you might need to scale up considerably to break even from a financial perspective. You might have a plant that produces 10-100 GW and a final size that would put a whole farm of ITER tokamaks to shame.

Of course if you have a secrete recipe for making muons in situ in the fusion chamber cheaply and in great profusion, then the story is different. Maybe Rossi should be put on the project!

*Actually a much smaller accelerator would be needed to produce a few muons, but it is not a question of making muons, but of making muons in relatively tremendously huge quantities. And the efficiencies may be much lower than stated. Making muons at one percent efficiency (energy in vs muon energy out) may be optimistic.

Dan Tibbets
To error is human... and I'm very human.

Joseph Chikva
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Joined: Sat Apr 02, 2011 4:30 am

Post by Joseph Chikva »

D Tibbets wrote:Actually a much smaller accelerator would be needed to produce a few muons,...
Much smaller than what? Than today's (yesterday's 70s of past century)? The fact in that they could not make muons with the help of smaller accelerators despite of many attempts. And that's all I can say you. Also all muon catalyst researchers estimated equal consumption of muons 1-2% from fusion events quantity. Make all calc on base of these data. And also take into account that effeciency of accelerator has about 25-35% order. Higher energies less as multistage acceleration cycles are required.

D Tibbets
Posts: 2775
Joined: Thu Jun 26, 2008 6:52 am

Post by D Tibbets »

From a theoretical perspective, only a few hundred MeV is needed to create a muon spontaneously or more likely as a result of collisions of particles with KE higher than a few hundred MeV. A room sized accelerator may reach these energies, or even smaller accelerators if new laser accelerators become pratical.

The question is not so much how difficult it is to produce muons, but how difficult it is to produce AND detect these muons. With their short half life, and rarity, it is a challenge, unless you have the appropriate detector, excess energy and perhaps most important a production rate that is adequate. It is not so much a question of voltage (KE) once past the threshold, but a matter of current- the number of particles necessary to reach some goal. My point has been that producing muons is not difficult, but producing muons in adequate numbers is extremely difficult and costly.

The same applies to D-D fusion. It is very easy to do, it is more difficult to do in quantities that is detectable without heroic detection efforts, and it is much harder to produce D-D fusions in numbers that results in significant power. And this is ignoring the cost/ Q considerations.

Dan Tibbets
To error is human... and I'm very human.

Giorgio
Posts: 2830
Joined: Wed Oct 07, 2009 6:15 pm
Location: China, Italy

Post by Giorgio »

Torulf2 wrote:Look that that man has done before.
http://www.couriermail.com.au/news/feat ... 1119160884
Good find indeed.
So in the end it was the father who started the business and the son is now bringing it forward. It's amazing, these guys are bringing this on from more time than Steorn and BLP together.

A real (first?) example of generational vapor-ware business!

seedload
Posts: 1062
Joined: Fri Feb 08, 2008 8:16 pm

Post by seedload »

Giorgio wrote:
Torulf2 wrote:Look that that man has done before.
http://www.couriermail.com.au/news/feat ... 1119160884
Good find indeed.
So in the end it was the father who started the business and the son is now bringing it forward. It's amazing, these guys are bringing this on from more time than Steorn and BLP together.

A real (first?) example of generational vapor-ware business!
It is amazing. Dad first claims revolutionary electolosis process and then, when the scam publically falls completely on its face, changes the whole story to fusion and somehow manages to keep the scam going. And people wonder about Rossis end game. There is no end game.
Stick the thing in a tub of water! Sheesh!

Nik
Posts: 181
Joined: Thu Mar 12, 2009 8:14 pm
Location: UK

Slightly off-topic...

Post by Nik »

Shifting boxes in our loft recently, I came across 'The Jupiter Theft' (Moffit 1977), where-in aliens have mastered meson-powered fusion-- "It's easy when you know how..."

Ivy Matt
Posts: 700
Joined: Sat May 01, 2010 6:43 am

Post by Ivy Matt »

When dealing with a pion or a horse, one just lets nature take its course.
Temperature, density, confinement time: pick any two.

Giorgio
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Joined: Wed Oct 07, 2009 6:15 pm
Location: China, Italy

Post by Giorgio »

ROTFL :D

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