Unknown source
- Steven Sesselmann
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- Real name: Steven Sesselmann
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Unknown source
Hi Guys,
I have been playing around with some gamma spectroscopy, and after taking spectrums of all my known sources, I got desperate, and took this overnight spectrum from the tiny check source on the side of my Leni geiger counter.
There are clearly some identifiable bumps there, but what is the substance?
I have drawn in some approximate values, based on my check sources.
Steven
I have been playing around with some gamma spectroscopy, and after taking spectrums of all my known sources, I got desperate, and took this overnight spectrum from the tiny check source on the side of my Leni geiger counter.
There are clearly some identifiable bumps there, but what is the substance?
I have drawn in some approximate values, based on my check sources.
Steven
- Attachments
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- Unknown.pdf
- (116.75 KiB) Downloaded 259 times
http://www.gammaspectacular.com - Gamma Spectrometry Systems
https://www.researchgate.net/profile/Steven_Sesselmann - Various papers and patents on RG
https://www.researchgate.net/profile/Steven_Sesselmann - Various papers and patents on RG
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- Posts: 307
- Joined: Sat Aug 27, 2005 8:30 am
- Real name: rich normand
Re: Unknown source
Here is a link of some common check sources used on survey instruments that could be of some help.
http://www.orau.org/ptp/collection/civi ... ources.htm
Just a guess, decay products from radium would have some peaks aroud 240, 295 and 350 from Pb214. This would also have Bi214 around 660. I would guess the peak at the far right (about 1400?) to be K40 from background? But it does look weak indeed. It is also difficult to tell how linear your scale is.
Just a guess, others on this site are much more qualified than me for this!!!
have fun!
http://www.orau.org/ptp/collection/civi ... ources.htm
Just a guess, decay products from radium would have some peaks aroud 240, 295 and 350 from Pb214. This would also have Bi214 around 660. I would guess the peak at the far right (about 1400?) to be K40 from background? But it does look weak indeed. It is also difficult to tell how linear your scale is.
Just a guess, others on this site are much more qualified than me for this!!!
have fun!
Re: Unknown source
Yes Potassium K40, (prob)
Try it again on the salt
Steve.
Try it again on the salt
Steve.
- Carl Willis
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- Real name: Carl Willis
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Re: Unknown source
Hi Steven,
Those CDV sources are usually either DU metal chips or a so-called "Radium D-E" source (Pb-Bi-Po-210).
Your spectrum is a bit difficult to interpret because of a heavy continuum of counts drowning any real distinct peaks.. If you can get a single-isotope, single-energy test source (e.g. Cs-137) to aid in setting up your audio pulse-shape processing, you will get much better results out of this apparatus. It's possible to do quite well with it as I have found, but it's not exactly "plug and play" for scintillators.
-Carl
Those CDV sources are usually either DU metal chips or a so-called "Radium D-E" source (Pb-Bi-Po-210).
Your spectrum is a bit difficult to interpret because of a heavy continuum of counts drowning any real distinct peaks.. If you can get a single-isotope, single-energy test source (e.g. Cs-137) to aid in setting up your audio pulse-shape processing, you will get much better results out of this apparatus. It's possible to do quite well with it as I have found, but it's not exactly "plug and play" for scintillators.
-Carl
- Steven Sesselmann
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- Joined: Wed Aug 10, 2005 9:50 pm
- Real name: Steven Sesselmann
- Location: Sydney - Australia
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Re: Unknown source
Carl,
I already have three check sources, Am241, Ba133, and Cs137, and with my new USB bias, it really is plug and play. See pdf spectra below, I am getting really good definition.
I might send you one of these plug and play USB modules, they would be great on your fossicking trips
Steven
I already have three check sources, Am241, Ba133, and Cs137, and with my new USB bias, it really is plug and play. See pdf spectra below, I am getting really good definition.
I might send you one of these plug and play USB modules, they would be great on your fossicking trips
Steven
- Attachments
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- Am241.pdf
- (53.79 KiB) Downloaded 244 times
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- BA133s.pdf
- (74.32 KiB) Downloaded 247 times
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- Cs137.pdf
- (79.44 KiB) Downloaded 250 times
http://www.gammaspectacular.com - Gamma Spectrometry Systems
https://www.researchgate.net/profile/Steven_Sesselmann - Various papers and patents on RG
https://www.researchgate.net/profile/Steven_Sesselmann - Various papers and patents on RG
Re: Unknown source
Wow - Jon you need to watch out - the apprentice may challenge the master
Congrats Steven - a great effort
Congrats Steven - a great effort
- Richard Hull
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- Real name: Richard Hull
Re: Unknown source
I think you have a weak natural uranium or radium source. Lotsa' bumps usually mean radium or natural U ore.
Based on your collection time, I think you are looking at background and there is not a real sorce there at all.
Richard Hull
Based on your collection time, I think you are looking at background and there is not a real sorce there at all.
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
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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Re: Unknown source
If it's anything like the ENI's that I have then it has a that the check source is most likely what they call a "Radium DEF" source. According to my research it's actually just a generic radium266 source with a number of radium daughters and various contaminants. Pretty much just a mix of radioactive debris, the quality control was miserable on these things.
The DU check sources that I have are several times more active than the sources on my ENI's which makes it very easy to discriminate between the two.
I'm wondering if the 230k peak is actually the Bi & Po K x-rays around 200k:
http://www.radiochemistry.org/periodict ... /ra226.pdf
If you want to really dig into it knock yourself out here:
http://ie.lbl.gov/decay.html
The DU check sources that I have are several times more active than the sources on my ENI's which makes it very easy to discriminate between the two.
I'm wondering if the 230k peak is actually the Bi & Po K x-rays around 200k:
http://www.radiochemistry.org/periodict ... /ra226.pdf
If you want to really dig into it knock yourself out here:
http://ie.lbl.gov/decay.html
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- Site Admin
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- Real name: Frank Sanns
Re: Unknown source
I am in the background radiation or weak shielded source camp here too. Check out for a relalvent experment. viewtopic.php?f=18&t=7754#p55713
Mild shielding from dirt, walls or any other Z including air will affect the lower energy peaks the most and can turn them into a continuum. Higher energy peaks will be less affected and could explain why you see higher energy bumps but a big undefinded mass of lower energy photons.
Frank Sanns
Mild shielding from dirt, walls or any other Z including air will affect the lower energy peaks the most and can turn them into a continuum. Higher energy peaks will be less affected and could explain why you see higher energy bumps but a big undefinded mass of lower energy photons.
Frank Sanns
Achiever's madness; when enough is still not enough. ---FS
We have to stop looking at the world through our physical eyes. The universe is NOT what we see. It is the quantum world that is real. The rest is just an electron illusion. ---FS
We have to stop looking at the world through our physical eyes. The universe is NOT what we see. It is the quantum world that is real. The rest is just an electron illusion. ---FS