Pion/Muon Injection

For the design and construction details of ion guns, necessary for more advanced designs and lower vacuums.
Post Reply
ironman68
Posts: 2
Joined: Fri Mar 15, 2013 10:24 pm
Real name:

Pion/Muon Injection

Post by ironman68 »

Would it be possible to give a +pion/+muon enough inertia to overcome the magnetic field allowing it to slam into the traffic jam of protons at the center of the fusor? This may be the spark needed to kick off fusion on a larger scale. From what I've read about Muon catalyzed fusion, the muon should have a long enough half life to orbit 300 proton pairs before disintegrating into other particles. Perhaps this 300 value would be much higher in the center of the fusor where all the action is?

Thanks for your thoughts.
User avatar
Carl Willis
Posts: 2841
Joined: Thu Jul 26, 2001 7:33 pm
Real name: Carl Willis
Location: Albuquerque, New Mexico, USA
Contact:

Re: Pion/Muon Injection

Post by Carl Willis »

Please read the four rules for posting, and change your username to your real name and post an introduction in the forum for that purpose as the rules require.

Please also spend some time reading background on the Farnsworth fusor. Your question suggests elementary misconceptions about how it works. No magnetic field contributes to the operation of the fusor. You might also productively read through the archived discussions about muons, aided by our handy search feature. Yes, muon-catalyzed fusion is a thing, reported in various scientific literature. The hobby fusion community cannot practically study it. The rest mass energy of muons and their parent particles is far too high to be accessible with hobby equipment. When hobbyists show up to this community with GeV-class linacs in their back yards, I am sure the discussion about muons will be fruitful and highly relevant. Until then, it's likely to remain the kind of discussion topic that our audience will roll their eyes at and troll, as they have done in the past when muons have come up.

-Carl
Carl Willis
http://carlwillis.wordpress.com/
TEL: +1-505-412-3277
terryphi
Posts: 21
Joined: Fri Nov 09, 2012 1:08 pm
Real name:

Re: Pion/Muon Injection

Post by terryphi »

Although this is horribly off topic, I did have a friend who did detect some Muons from cosmic rays using vertically stacked detectors and a coincidence circuit, so I I wouldn't say that Muon research is entirely off limits to the amateur circuit....well, the production of Muons yes, but Muons nonetheless.
User avatar
Chris Bradley
Posts: 2930
Joined: Fri May 02, 2008 7:05 am
Real name:

Re: Pion/Muon Injection

Post by Chris Bradley »

Just to clarify - muon fusion requires very cold muons, not fast cosmic muons. This is because they need to create a 'hybrid atom' of deuterons, in which the 'heavy' negatively charged muon becomes the centre of the 'atom' and two deuterons orbit around it, like a reverse of a normal atom. This only happens in low energy frames, not with high energy muons. After that, because the deuterons are so close together (like electrons in an atom) and for such a relatively long period, they have a chance of fusing by quantum means.
User avatar
Carl Willis
Posts: 2841
Joined: Thu Jul 26, 2001 7:33 pm
Real name: Carl Willis
Location: Albuquerque, New Mexico, USA
Contact:

Re: Pion/Muon Injection

Post by Carl Willis »

Sure, "muon telescopes" and various other detectors for the low-level cosmic secondary muon flux are pretty well known among nuke hobbyists.

Any background reading on the subject of muon catalyzed fusion will inform interested people that to produce fusion rates we might consider detectable requires the world's largest accelerator facilities, cranking out muons at a rate that is probably on the order of billions of times more intense than cosmics. If someone wants to make the serious argument, from an informed position, that cosmic muons can be used in practical muon-catalyzed fusion experiments, then they should feel at liberty to describe how that would work and, better yet, get their hands dirty implementing it. I'm not holding my breath! (A quick read through the archived discussions about muons and fusion is downright depressing for the lack of background reading in evidence.)

-Carl
Carl Willis
http://carlwillis.wordpress.com/
TEL: +1-505-412-3277
Dan Tibbets
Posts: 578
Joined: Thu Apr 17, 2008 1:29 am
Real name:

Re: Pion/Muon Injection

Post by Dan Tibbets »

Fusion due to cosmic rays (actually from secondary muons from cosmic ray hits in Earth's upper atmosphere) is a simple experiment to demonstrate. Take a bowel of heavy water, let it sit for a few years, then measure the accumulated He3. Since this has not been reported, even with scaling up to much larger containers of water, I take as an indication that it is a hopeless endeavor. The fusion cross section for deuterium is so low at room temperatures, even improving the likelihood with muons a few million fold will not result in measurable fusion.

In a fusor, the temperature is greater and thus the fusion cross section is more reasonable, but the density is perhaps less by a factor of 100,000. That means density dependent fusion rates would be ~ 100,000,000 times less. The few natural muons that enter the chamber and catalyze a few, or even a few hundred fusions does not make a difference in the measurable fusion rates- the uncertainty in the measurements completely dwarfs any contribution from the muons. As mentioned, artificial muons from an accelerator would have to be supplied at concentrations many orders of magnitude greater than the natural muon flux to make a detectable difference.

And of course it costs lots of energy to produce muons in an accelerator. Considering inefficiencies, it might take ~ 1 GeV or more to make each muon, and to recover that energy it might take ~ 300-1000 catalyzed D-D fusions. Then there are the problems of maintaining the muon participation in the fusion process even as long as it's short half life. Read about muon catalyzed fusion in Wikapedia.

Dan Tibbets
User avatar
Chris Bradley
Posts: 2930
Joined: Fri May 02, 2008 7:05 am
Real name:

Re: Pion/Muon Injection

Post by Chris Bradley »

Dan, Carl has just flagged a warning of poor reading. Muons at sea level are all highly relativistic (as otherwise they'd not make the journey from top of atmosphere to ground). They will flash through your bowl of heavy water almost as if it was not there. They need to form this 'hybrid molecule' before inducing any fusion, and there's no chance of that with a penetrative power of many meters of rock.
ironman68
Posts: 2
Joined: Fri Mar 15, 2013 10:24 pm
Real name:

Re: Pion/Muon Injection

Post by ironman68 »

Gents,

I ran across the following company:

http://www.starscientific.com.au/the-st ... akthrough/

Now if they would just talk to the Polywell folks.
User avatar
Carl Willis
Posts: 2841
Joined: Thu Jul 26, 2001 7:33 pm
Real name: Carl Willis
Location: Albuquerque, New Mexico, USA
Contact:

Re: Pion/Muon Injection

Post by Carl Willis »

Bring your registration into compliance with the rules if you want to comment on fusor.net. Your account will be frozen if you keep posting pseudonymously and with no introduction.

The site you linked is not distinguishable from quackery. You can find quackery and misinformation everywhere online for a topic as sensational as fusion energy. There are enough incurious, uneducated, dreamy, conspiracy-minded, and idle folks in this world to keep the quacks and pseudoscientists in business. The focus on fusor.net is "open-source" discussion about real, amateur (non-commercial), fusion projects. Discussions about commercial projects and quackery are the last thing we want you to bring here.

-Carl
Carl Willis
http://carlwillis.wordpress.com/
TEL: +1-505-412-3277
Post Reply

Return to “Ion Gun Design and Construction (& FAQs)”