isotropic neutron measurement

It may be difficult to separate "theory" from "application," but let''s see if this helps facilitate the discussion.
Jake Wells
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Re: isotropic neutron measurement

Post by Jake Wells » Thu Apr 24, 2014 12:09 am

thank you for helping me on the math I really appreciate it.

-Jake Wells
“The day science begins to study non-physical phenomena, it will make more progress in one decade than in all the previous centuries of its existence.”
― Nikola Tesla

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Richard Hull
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Re: isotropic neutron measurement

Post by Richard Hull » Thu Apr 24, 2014 5:55 pm

Before one gets to full of oneself with precise math calculations, There are about 10 or more issues that throw flies into the ointment. As such, you must realize it is all highly imprecise as assumptions are made throughout the process that just aren't that well controlled or even controlable.

Is the fusor external neutron emission uniform? Not really
Is it a stable emitter over time? Absolutely not.
Is the fusor a point source? It is NOT!
Is the detector fixed forever? In most cases, it is not.
Is the final count rate at the end of a timed run huge or small? If huge, you are better off and, within the above issues, your reduction more reliable. 20-30 counts over 10 minutes will pin things down poorly; while 16,340 counts over the same period will be far more valuable. This has to do with detector efficiency.

I have said this many times........You will never know the exact emission to better than 10-20%. However, you can gauge improvements in performance, run-to-run, rather easily, to within 1%!

You might say....Why bother? Again, it is all better than a poke in the eye with a sharp stick.

I hated casting these pearls of widom here.............It is the wrong forum! Folks wanting to know about neutron counting and neutron numbers will not expect this here, but search in the proper forum "neutron and radiation detection", missing all of this!

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
Retired now...Doing only what I want and not what I should...every day is a saturday.

Jake Wells
Posts: 87
Joined: Wed Mar 19, 2014 1:29 am
Real name: Jake Wells

Re: isotropic neutron measurement

Post by Jake Wells » Thu Apr 24, 2014 8:40 pm

I know that my TIER neutron rate will never be precise but car my calculations in the right ball park?
This is my last question any more will be put in the neutron radiation column. Sorry for the mix-up.
“The day science begins to study non-physical phenomena, it will make more progress in one decade than in all the previous centuries of its existence.”
― Nikola Tesla

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Richard Hull
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Re: isotropic neutron measurement

Post by Richard Hull » Fri Apr 25, 2014 6:34 am

Yes, they can be in the right ball park, provided you try and control the fusion rate over the timed period, (maintain a rather steady voltage, current and D2 pressure), and develop a good detection scheme.

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
Retired now...Doing only what I want and not what I should...every day is a saturday.

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