Proton-boron Success! - Nope!

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Jason C Wells
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Proton-boron Success! - Nope!

Post by Jason C Wells »

Tonight (this morning) I successfully conducted the proton-boron fusion reaction.

These results should be considered preliminary. I observed extremely bright scintillations on a zinc-sulfide screen that employed a foil filter to block low energy protons but allow high energy alphas. I'll have my professor over to critique my work as soon as I can. I am too excited to say nothing, so you get caveat emptor in the mean time.

Regards,
Jason C. Wells
Last edited by Jason C Wells on Fri Sep 25, 2015 8:54 pm, edited 1 time in total.
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Dennis P Brown
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Re: Proton-boron Success!

Post by Dennis P Brown »

Protons or some other charged particle scintillating upon a ZnS screen is not final proof of boron fusion even if you have a low energy filter (like what? An Al foil 25 microns thick (off the self aluminum foil) will fully stop 5 MeV protons so even if your He nuclei have 8.7 MeV energy (for boron/proton fusion) I doubt they could significantly penetrate through a standard aluminum foil for a signal upon your ZnS screen.); remember, you need a lot of hard data to support a claim. So details of the experiment are critical.
I see you have an accelerator so I assume you are using protons to bombard a boron target? What energy do you think you your accelerator is producing and what is your proton current (as measured, not calculated)? Have you calculated the penetration depth of He+2 ions through Al at 8.7 MeV? What percent of ions should get through?
Regardless, that is outstanding that you have your accelerator finally working! and I look forward to seeing more details.
That all said, I am glad you got results that excite you! Regardless, that is always fun. Just remember, you need to carefully consider all aspects of your experiment.
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Jason C Wells
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Re: Proton-boron Success!

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The foil is specialty foil at 7 micron thick. The maximum theoretical output of the VDG is 600 KeV. The stopping distance of 600 KeV protons in aluminum is 6.9 micron. The alpha from proton-boron is 3MeV and greater. The stopping distance of the lowest energy alpha in aluminum is 10.7 micron. Proton current at the target is 2-4 μA.

VDG output is nominally 300 KeV as determined by 8 inch spark gap, but it wasn't putting out that much last night. That's not critical to verifying fusion though. That just tells you where on the cross section curve you were operating. I was probably closer to the 150 KeV resonance peak than the 560 MeV max cross section.

I read the post on making fusion claims here. I did say preliminary. I probably won't meet the "data" criteria for a long time since I don't have spectroscopy. I will have just as supportable a claim as Oliphant had when Rutherford stuck his head up that box and said, "It looks like you've got alpha." I appreciate the hard skepticism and I do plan on working toward spectroscopy. The hard skepticism helped me get to this point!

I have to put together documentation to complete my degree. I will share that here in fine fusor.net fashion.

Regards,
Jason
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Jason C Wells
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Re: Proton-boron Success!

Post by Jason C Wells »

Here is a crude smart phone video.

https://www.facebook.com/jason.c.wells/ ... 921719544/

And a still photo of the same stuff with the lights on. The circular shape on the steel pipe inside the glass tube is the alpha window. That circle covers a hole in the steel pipe. On the inside diameter of the steel pipe is the foil screen.

https://www.facebook.com/photo.php?fbid ... 537&type=3
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Jason C Wells
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Re: Proton-boron Success! - Nope!

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I ran a control test with air rather than hydrogen. The results were somewhat different. I still got scintillations though. This negates my result from two days ago. Rather, I may have had fusion two nights ago, but I cannot authoritatively claim to have done so because my detectors produce scintillations when there are no protons.

There are other control tests to perform. I will run a test with hydrogen and no boron also.

My target bias and beam current measuring are not robust. I have to sort that out.

I currently cannot see the target. I am going to update the design to allow viewing the target directly.

Regards,
Jason C. Wells
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Richard Hull
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Re: Proton-boron Success! - Nope!

Post by Richard Hull »

You are doing it in a correct manner, of course. Alphas are classically best detected with a PIPs detector coupled to an alpha spectrometer to verify energy levels. Too many things can cause scintillations on a ZnS screen.

Can you verify your exact applied voltage under the load of the accelerator? I mean critically and accurately measured rather than make an assumption based on spark distance jumped in air without the accelerator load. Current is not important to know here, only voltage. The current would be vanishingly small regardless of voltage actually working under load.

Richard Hull
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Fusion is the energy of the future....and it always will be
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Re: Proton-boron Success! - Nope!

Post by Dan Tibbets »

Stoping protons with a given filter/ barrier is fine. But, you must consider the Maxwelliam/ Boltzman distribution of the protons. With an average proton beam energy of 600 KeV, the distribution will have some at substantially lower and higher energies. Only if you proton beam was non thermalized/ monoenergetic would the barrier be highly efficient. Even then, interaction with the target would probably introduce some energy spread, secondary protons with a significant thermal spread. You might get some useful signal, but I suspect it would need to be a substantial difference over controls.

Dan Tibbets

Dan Tibbets
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Jason C Wells
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Re: Proton-boron Success! - Nope!

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Richard Hull wrote:Can you verify your exact applied voltage under the load of the accelerator?

Richard Hull
I cannot. I envisioned a day when I had spectroscopy to measure incident particles. Then I could know energies at the target. I'm not there yet.

A couple years ago I concluded that measuring the voltage of a Van De Graaff was tricky business and decided that if I got far enough for it to matter, that I would work harder at instrumenting the Van De Graaff. I might be there now.

Regards,
Jason
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Richard Hull
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Re: Proton-boron Success! - Nope!

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Usually, the slightest load on a common experimenter's Van De Graaff, even a large one, will virtually kill the potential or drag it down significantly.

Richard Hull
Progress may have been a good thing once, but it just went on too long. - Yogi Berra
Fusion is the energy of the future....and it always will be
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Steven Sesselmann
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Re: Proton-boron Success! - Nope!

Post by Steven Sesselmann »

Jason,

I have not been active on the forum lately and have not followed your progress.

Can you refer me to a post which describes your p+B11 setup?

Steven
http://www.gammaspectacular.com - Gamma Spectrometry Systems
https://www.researchgate.net/profile/Steven_Sesselmann - Various papers and patents on RG
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Dennis P Brown
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Re: Proton-boron Success! - Nope!

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The best approach to getting an approximate check on a VdG's voltage is to use a second sphere (should not be too small but does not need to be similar in size, either.) Ground this second sphere, run the VdG and slowly move the second sphere closer to the VdG. This must be done in very dry air, of course. When the air breaks down and the arc jumps, measure the distance in centimeters. This gives a rough measure of the voltage.
How did you measure the proton current? I'd like to know since that would be useful once (or if?) I ever get mine working ... .
Also, how did you measure your Van de Graaff current?
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Re: Proton-boron Success! - Nope!

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The arc method is fine provided, and only if, it is done under full load with the VDG hooked to a working accelerator that is in full load operation. Just jumping an arc in air with the generator just sitting there in an unconnected condition, tells you nothing related to its voltage output in an "in use situation" hooked to a load.

The two are vastly different. Depending on the load and the VDG, Most VDGs will not produce even 5% of their no load, arc measured, voltage when loaded in an accelerator application.

VDG's or any static machine, for that matter are some of the highest internal impedance HV power sources known to man and can not supply much vlotage, current or power at all to a load.

Richard Hull
Progress may have been a good thing once, but it just went on too long. - Yogi Berra
Fusion is the energy of the future....and it always will be
The more complex the idea put forward by the poor amateur, the more likely it will never see embodiment
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Jason C Wells
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Re: Proton-boron Success! - Nope!

Post by Jason C Wells »

You can easily measure the current that the drive belt can deliver to the VDG terminal. You can easily measure the dead short current that the VDG terminal can provide to ground. These things don't tell you what's going on during nominal operation though. They do tell you order of magnitude sort of information. I use them for the purpose of determining if what I am seeing makes any sense.

Proton current at the ion source can be deduced from the current supplied to the ion source assuming equilibrium and charge conservation, perhaps a bad assumption since we don't know where the charge leaks are. My ion source is akin to a Penning trap. I measure the current supplied from a 5000v potential across one stage of a small ladder multiplier. When pressure is low my penning source will draw about 50 microamps. My ion source should be able to deliver a maximum of 50 microamps of protons assuming perfect efficiency. The glow out of the penning source at this pressure is barely perceptible even after becoming accustomed to the darkness in my garage.

Proton current at the target end of things is as simple as putting a meter between the target and ground, except it isn't. I measured 10 microamps at this end, but that includes ejected secondary electrons travelling opposite direction back up the accelerator column. Just about the time I was getting some target bias set up, I fried my ammeter. I also don't know how many protons get stuck on the inside wall of the glass due to poor beam collimation. If I ballpark the beam current to be something less than 10 microamps, say 1 microamps, then my entire beam line is about 2% efficient. But all of this is a swag.

I just got a new ammeter tonight. (Actually I bought three. Two to use and one for a spare.) This $15 dollar student desktop meter has proven surprisingly robust. It only failed when I applied 400 VDC through it to ground due to fat fingers.

I don't know if that helps you Dennis. A sparky has a better intuition than I do for these sorts of things. Feel free to ignore dumb things that I wrote. You are probably right and I am probably wrong.

Regards,
Jason C. Wells
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Dennis P Brown
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Re: Proton-boron Success! - Nope!

Post by Dennis P Brown »

Thanks for the description and details; 1 microamp sounds reasonable for a current on an operational accelerator and measuring the current directly at the target is a good method but, as you correctly point out, secondary electrons will cloud the results. I think you are doing good work and any accelerator project - especially one that uses a Van de Graaff - is a battle to fix issues to achieve sufficient voltage potential; I know only too well about those issues. I still feel you need to get rid of the wood box and use Plexiglas around your VdG - at least replace the wood section that the accelerator tube pass's thru with plexiglass. Wood, with its high water content is a very good conductor (at VdG voltages) and will hurt the systems ability to achieve full potential.
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Jason C Wells
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Re: Proton-boron Success! - Nope!

Post by Jason C Wells »

I've been thinking about ditching the wood box prior to your most recent post, but I've got everything "installed" right now and other things are causing me trouble. Also, the wet season in Seattle is upon me. So I might need me environmental chamber anyway. Right about the time I get everything else sorted out, humidity will be back causing me trouble.

Regards,
jason
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Jason C Wells
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Re: Proton-boron Success! - Nope!

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I missed a comment by Steve Sesselman. Steve, I describe my apparatus as proton-boron fusion in a linear accelerator, PBFLA for short. I haven't posted any documents yet. My equipment is: a 600kV Van De Graaff, a modified penning trap to ionize hydrogen, a Hofmann apparatus, a custom glass accelerator column, a diff pump, rough pump, a 400V battery, a Cockroft-Walton ladder multiplier, and assorted plumbing bits and pieces. A crude and obsolete schematic is attached. It should be sufficient to get the main idea across.

Regards,
Jason
A schematic of proton-boron fusion in a linear accelerator.
A schematic of proton-boron fusion in a linear accelerator.
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Steven Sesselmann
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Re: Proton-boron Success! - Nope!

Post by Steven Sesselmann »

Jason C Wells wrote:I missed a comment by Steve Sesselman. Steve, I describe my apparatus as proton-boron fusion in a linear accelerator, PBFLA for short. I haven't posted any documents yet. My equipment is: a 600kV Van De Graaff, a modified penning trap to ionize hydrogen, a Hofmann apparatus, a custom glass accelerator column, a diff pump, rough pump, a 400V battery, a Cockroft-Walton ladder multiplier, and assorted plumbing bits and pieces. A crude and obsolete schematic is attached. It should be sufficient to get the main idea across.
Jason, thanks for the schematic, so if I understood this correctly the VDG is inside the vacuum chamber, very neat idea, I hope you get results.

I prefer negative acceleration into a negative target but so far I only have theoretical evidence of this being a better approach.

Steven
http://www.gammaspectacular.com - Gamma Spectrometry Systems
https://www.researchgate.net/profile/Steven_Sesselmann - Various papers and patents on RG
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Jason C Wells
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Re: Proton-boron Success! - Nope!

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The box around the VDG is just for humidity control and is at atmospheric pressure. The interior of the sphere is also at atmospheric pressure. I can see from the schematic how it can be confusing. (Sorry for the late reply. I've been away from my project for a time.)

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Jason C. Wells
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Dennis P Brown
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Re: Proton-boron Success! - Nope!

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Again, I strongly suggest you get rid of the wood box; it will draw current from the machine. Use a plexi-glass box. Thin sheets aren't that expensive. At least at the exit port of the accelerator tube. There the wood will really act as a conductor!

I am, as you may note from my posts trying both a very large VdG and building a rather massive voltage multiplier for my deuteron accelerator. Best of luck with your system. Keep up the work - it takes time but is worth it - do avoid exploding caps as I just failed to do (lol.).
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Jason C Wells
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Re: Proton-boron Success! - Nope!

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The box will be deleted during my next foray into my project. I was able to observe a sporadic large umbrella shaped plasma that terminated on the plywood box. This confirms your claim that the box is a problem.

I am also planning on incorporating a ladder multiplier. VDGs are too finicky in my opinion.
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Dennis P Brown
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Re: Proton-boron Success! - Nope!

Post by Dennis P Brown »

LOL on the VdG issues! Know only too well and why I am attacking that issue a number of ways: a very large VdG (posted) and two approaches to a high voltage multiplier (VM; one system I have posted images the other still in the works and will be posting some aspects.)

A few words of advice on the VM: use a high frequency supply if possible; 60 Hz isn't easy to do (but the diodes sure are cheap.) While I have achieved over 40 kV using a NST (7.5 kV) and intend to top out a good bit higher, that system is rather large - certainly inexpensive but very large and will require oil. Lots of stages is not the best approach; of course, with a high freq. power supply one can get away with more stages. Also, flybacks require high freq. to drive them. They can give you both more voltage and power for the buck.

Best of luck and really look forward to your progress and results!
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