IEC Fusion - Neutron Club Entry

[Bern Bareis]

Operation on April 22, 2015: 15 minute run time, -25kV to -26kV at 5 mA to 7 mA.
Result: 4 Bubbles on BTI BD-PND67 Dosimeter (closest point located 8.04 cm from center of cathode).

High Voltage Power Supply:

Cathode:

BTI BD-PND67:

[Rich Feldman]

That was fast! Looking good there Bern. If you are planning to stick around after the neutron club discussion, do you want to reconcile your BTI counts with your NeutronRAE counts?

If I were a judge, it would be time to remind you again -- it takes more than a convincing demonstration of neutron production. In most contests and clubs, following the rules is important. It demonstrates respect for the institution and the other members.
So, now sticking my neck out, do any other participants agree? Has anyone ever seen a neutron club application with so many sections not filled in? Details so easy that persistently skipping them could be seen as flaunting a cavalier attitude. The rules are posted for all of us to read, so I will just point out a few lines.

The following will be demanded for neutron club membership.
...
1. You shall have been a poster and member of the forums for at least 60 days.
...
4b. An image of the entire fusor setup with neutron detection assembly in place with yourself in the image with the device. (all must be visible.)
...
4c. A full data set to include ... Operational pressure of the Deuterium fuel in the fusor during fusion. Show metering. [during the same run as the claimed neutron count was collected]
...
Several fusion runs with several sets of data as noted above will be preferred. [ e.g. a 15 minute run with different voltage, current, pressure, or gas, resulting in fewer or no bubbles. Evidence of scientific method. ]

A personal note, after looked through the posting history of the last 10 or 15 neutron club inductees. What leaps out, and I think is unprecedented, is that you have not yet posted a single word about Bern.

Why do you want to be in the neutron club? What other clubs are you in? Are you in a hurry, or can't spare much more time for this particular notch? Do you think the decision should be objective and mechanical (please tell us which rules should matter and which are unimportant) or somewhat colloquial (in which case, who are you?).

Best regards,
Rich

[Richard Hull]

The data is believable at last. I have a good deal of experience with BTI detectors and considering the voltage, current and the images, I am placing you in the Neutron club. Good work in going through the extra effort.

Richard Hull

[Rich Feldman]

You won this one, Bern. Let me be the second fusor.netter to congratulate you.

Are you going to carry on with your fusor? It would be great to see count values from the NeutronRAE II at your new, higher voltage levels. With and without moderator, of course. The guy from RAE did recommend a moderator for maximizing the count values. As discussed in another thread, we think your datasheet interpretation is unrealistically favorable to the instrument. D/s does give sensitivity as 1 to 2 cps (for an unspecified energy spectrum). It does say energy range for detection (with unspecified sensitivity) is thermal to 14 MeV.

How do you feel about telling us about yourself, now that your name is on the honor roll?
Must we continue to use our imaginations?

[Bern Bareis]

Thank you Richard H.

[Bern Bareis]

Additional data April 25, 2015: -28kV 5.5mA to 7mA, 20 minute run time, 67 b/mrem BTI BD-PND67.
Cathode:

Result: 14 Bubbles

14 bubbles.JPG (16.43 KiB) Viewed 6892 times

[Rich Feldman]

Excellent ! What''s that rate in neutrons/cm^2/s, and total fusor neutrons/s?

[Richard Hull]

While this would be great to know and is really icing on the cake, the calcs are easy to do and I posted them a while back. You need to know the distance from the fusor the total run time and that calibration constant for the BTI, and the dose rate number of 2.5mev neutrons/sqcm per mrem/hour.

Work the bubble count to mrem dose
convert to a rate mrem/hr
then figure the flux required to get that rate
figure neutron emission/sec over the entire spherical area at the range used
Double the result to get total fusions/sec in the fusor.

The answer should be within +/- 20%

Not highly accurate as absolute counts go, but it is better than a poke in the eye with a sharp stick and you are smarter and have more data in hand when done. Give it a whirl.

Richard Hull

[Bern Bareis]

[Bern Bareis]

As a scale reference, the cathode grid is 1 inch in diameter and the poissor is approximately 0.1 inch in diameter in this image.

[Rich Feldman]

Good stuff there, Bern. Thanks for coming back to share it.

Your spreadsheet cell titles, including proper symbols for units of measurement, are exemplary. An independent calculation from the same inputs gave the exact same outputs.

I didn't know that poissors came as compact as the one in your picture. Can you tune for smalless? The grid's equatorial ring appears hotter than the other rings. How, if at all, are the rings bonded where they cross?

Now a few questions/comments offered as helpful critique, not criticism.
What are the voltage, current, and pressure for the poissor picture? Some guesses can be made from its filename.
In your spreadsheet it looks like yellow cells are for inputs and green ones for outputs, with the rest being intermediate results. Isn't the 3.70E-05 an input here, in the same category as the 67? (inputs not measured by you)
The word poissor seems to generally be spelled with an -or, not an -ar, unlike the Portuguese verb poisar.

To all:
Richard H says that poissor was derived from the name of Siméon-Denis Poisson. So until/unless corrected, I pronounce its first syllable like "pwis" or "pwahs". https://www.youtube.com/watch?v=7IyCfyiDfpU http://www.pronouncenames.com/pronounce/Poisson http://www.howdoyousaythatword.com/word/poisson/ Maybe that's pretentious. Americans can say derailer for derailleur, and Farve for Favre. The cgs unit of dynamic viscosity, poise ("pwahz"), is named for a different French scientist.

[Richard Hull]

Great image and great continued work and reporting on improvements and solid fusor operation. Doing fusion is fun. You have the complete hang of operation now as the images and data shows.

Could you give us your thoughts on the actual operation as you get your system up to fusion and keep it in the sweet spot zone during your long runs? It would be good to hear this from another newer fusioneer who seems to be doing it right.

Richard Hull