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"internal helium leak" may suggest Li-6 + Li-6 fusion!

Posted: Sat Jun 25, 2016 2:07 pm
by Sven Andersson
Scientists in my country have measured the weight of the Li-7 nucleus and at the same time took a stab at Li-6, see paper A new mass value for 7Li, which can be downloaded for free. During the Li-6 measurements they were pestered by an "uncontrollable internal helium leak" in the equipment. I suggest that this is due to Li-6 + Li-6 fusion reactions instead of a leak. Look at the table below of Li-6 fusion reactions; half of them produce alpha-particles!
ScreenHunter_339 Jun. 22 16.17.jpg
In the CRYSIS ion source (an EBIS) Li+ ions are bombarded by electrons until there is a population of Li3+ ions. Then an electric field is applied for a short time and the ions leave the CRYSIS and are weighed in a Penning ion trap. The elecric field I mention is important; it does the trick of fusion, I think. How? Probably by the same mechanism that it induces fusion in a deuterium ion source. It is quite well known, that if you build an ion source for deuterons, you must be very careful about the neutron and gamma radiation that is produced by the fusion reactions in the source.

I think like this: bare light nuclei + applied electric field (1-100 kV) = nuclear fusion

Unknowingly you Fusor people may have experience of this; you build Fusors and then attach an ion source and discover that it boosts fusion. The extra fusion may actually occur only in, or slightly 'after' the ion source itself.

OK; to be sure; there are helium leaks in vacuum equipment and my imagination may carry me too far on this. So what is your opinion?

Sven

Re: "internal helium leak" may suggest Li-6 + Li-6 fusion!

Posted: Sat Jun 25, 2016 3:24 pm
by Dan Knapp
Sven
The Penning trap has been investigated as a fusion source; see:
http://iec2015.es.titech.ac.jp/presentation/O-8.pdf
and references therein. Depending upon how the trap was gated, fusion is entirely possible.
Fusion in a Penning trap has not yet been documented, but theory says it is possible.
Theory also predicts that it may even be possible to exceed unity gain if the practical issues of high
Voltage standoff in a small dimension device can be overcome.

Re: "internal helium leak" may suggest Li-6 + Li-6 fusion!

Posted: Sat Jun 25, 2016 3:28 pm
by Dan Knapp
Sven
Your link to the paper does not work.

Re: "internal helium leak" may suggest Li-6 + Li-6 fusion!

Posted: Sat Jun 25, 2016 6:48 pm
by Roberto Ferrari
Nice suggestion!
Some fusorist has a RGA in order to check He rise after many fusor sessions?
Of course, it will require to run in a sealed mode.

Re: "internal helium leak" may suggest Li-6 + Li-6 fusion!

Posted: Sat Jun 25, 2016 11:48 pm
by Richard Hull
I am unaware of any fusioneer ever achieving a million neutrons/sec in a sealed chamber. I am not syaing it is impossible, just that it has never been done. One would need a clean RGA for at fusor run pressures, an RGA would be fouled rather quickly. Detectable He might not found in light running fusors.

I still posit that the reason we have to have flowing D2 is due to a rapid burying of deuterium atoms when working near the typical fusor best runs of 1 millon neut/sec and higher. The longest continuous "hot" runs of fusors are on the order of 30 minutes. Most runs are 10 minutes or so for data collection.

Richard Hull

Re: "internal helium leak" may suggest Li-6 + Li-6 fusion!

Posted: Sun Jun 26, 2016 8:29 am
by Sven Andersson
Dan Knapp wrote:Sven
Your link to the paper does not work.
Just Google "A new mass value for 7Li" and follow the first link to arxiv.org!

Re: "internal helium leak" may suggest Li-6 + Li-6 fusion!

Posted: Sun Jun 26, 2016 12:01 pm
by Jerry Biehler
You would need a pressure reducing setup for the RGA, this is a valve with an orifice and a separate turbo for the RGA. The RGA needs to be kept below -4 while it is running.

Re: "internal helium leak" may suggest Li-6 + Li-6 fusion!

Posted: Mon Jun 27, 2016 12:27 am
by Rex Allers
For anyone else who, like myself, didn't know what an RGA was...
Residual Gas Analyzer
a form of mass spectrometer. Got my small understanding from this Wiki page:
https://en.wikipedia.org/wiki/Residual_gas_analyzer

Re: "internal helium leak" may suggest Li-6 + Li-6 fusion!

Posted: Mon Jun 27, 2016 7:39 am
by Jeroen Vriesman
...."and a separate turbo for the RGA"....

That's not needed, I use a big valve between the turbo and the chamber, which is open during pump-down and bake-out, then the valve is closed, but it's bypassed with a throttle valve, so the pressure in the chamber can be medium vacuum, while the turbo creates a high vacuum.
Then the RGA is connected at the high vacuum side.

No second turbo needed.