x-ray spectroscopy of beam target for fusion-helium?

This area is for discussions involving any fusion related radiation metrology issues. Neutrons are the key signature of fusion, but other radiations are of interest to the amateur fusioneer as well.
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Harald_Consul
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x-ray spectroscopy of beam target for fusion-helium?

Post by Harald_Consul » Mon May 27, 2019 9:34 am

I have managed to get my x-ray scintillation probe running. I cannot tell about the its sensing quality yet. I just quick testet it in front of a CR-tube and measured, if it does produce a signal.

My approach is beam on target fusion (instead of plasma Hirschman fusor). If I could do an x-ray spectroscopy of the deuterium filled beam target (which is out of irridium or palladium material) afterwards the beam fusion experiment, the whole beam on target apparatus would be much more cheaper than live fusion detection. In this case I could use a vacuum chamber out of industrial steel pipes (instead of an apparatus that let neutrons - or in my setup gamma radiation - pass through the outer wall of the apparatus.)

Is it possible to do an x-ray spectroscopy for helium? If so, how can I do it the easierst and cheapest way?
Last edited by Harald_Consul on Mon May 27, 2019 12:42 pm, edited 2 times in total.

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Dennis P Brown
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Re: x-ray spectroscopy of beam target for fusion-helium?

Post by Dennis P Brown » Mon May 27, 2019 11:34 am

I am lost reading this part of your question: " If I could x-ray spectroscopy the deuterium filled beam target out irridium or palladium afterwards" where the bold is what I don't follow. Nor do I follow why "much more cheaper than live fusion detection" and why you think that is true? X-rays do not define fusion at all (of course, gamma rays are produced in essentially undetectable levels; though the energies can be the same for an x-ray and gamma ray, of course under special conditions but not at fusion energy levels. But using correct terms is important to be understood here) - neutrons are the only significant signal and that is why those are generally used by people trying to prove fusion.

As for spectral lines using x-ray illumination (what I infer that you are asking but if not, please clarify that too), this isn't something that can easily be done since it requires special crystals to separate and resolve the lines. These are weak lines so not sure a simple scintillation detector will easily cut it. Also, exactly what are you using for a source of x-rays? (If that is what you are saying - a fusor (except the 4Pi steradians flux from electrons on the walls for 30 kV and higher supplies) does not produce any significant high energy photons that you can measure (i.e. the gamma rays.)

If you are just trying to use x-rays for simple bulk absorption differences between a target with and without deuterium it is highly unlikely to work since signal differences will not be above your noise levels.

Harald_Consul
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Re: x-ray spectroscopy of beam target for fusion-helium?

Post by Harald_Consul » Mon May 27, 2019 12:39 pm

There were two words missing in my statement. It must be: "If I could do an x-ray spectroscopy of the deuterium filled beam target (which is out of irridium or palladium material) afterwards the beam fusion experiment, the whole beam on target apparatus would be much more cheaper than live fusion detection." (I have corrected it now.)

A deuterium ion beam is usually generated in vacuum, because air slows down the ion beam. Thus, a vacuum chamber is required to perform a beam on target fusion experiment.

I've been simply thinking about proving the fusion afterwards the experiment, by taking the target out of the vacuum chamber subsequent the experiment and examining it for helium in case generated by a fusion process. To do this I want to use x-ray spectroscopy.

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Dennis P Brown
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Re: x-ray spectroscopy of beam target for fusion-helium?

Post by Dennis P Brown » Mon May 27, 2019 9:54 pm

Thanks, that makes sense now; as for deuterium ion acceleration, I have gone that route and quit after building a fully operational accelerator; why? Before powering it up, I realized that my very high voltage multiplier was far too dangerous a supply to be open like the accelerator required; further, accelerators are very difficult to properly shield against the x-rays they create. Since a regular fusor was far safer I went that route instead. As for the very high vacuum required, that subject is all too well understood by me - lol. I laugh because building an accelerator system/target system that was good to the low 10^-6 torr required was a very tedious job.

The amount of helium a fusor or a low power accelerator would produce is extremely small and unfortunately, it is highly unlikely you will be able to detect any outside the noise level of your device. You might, instead, try activation of a target like silver using deuterium ions - that is within reach of your detector.

Harald_Consul
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Re: x-ray spectroscopy of beam target for fusion-helium?

Post by Harald_Consul » Thu May 30, 2019 8:24 am

Thanks Dennis.

There is only one point I do not understand. In which way would a silver target help me out of the helium detection problem?

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Richard Hull
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Re: x-ray spectroscopy of beam target for fusion-helium?

Post by Richard Hull » Thu May 30, 2019 8:34 am

It will not help at all except to indicate real fusion has taken place using a GM counter when the device is turned off. this is proof that 3He was produced. No activation of silver = no 3He and no fusion.

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.

Harald_Consul
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Re: x-ray spectroscopy of beam target for fusion-helium?

Post by Harald_Consul » Thu May 30, 2019 10:03 am


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