26.3 KeV Americium line?

[Daryl]

It's the blue one at the far left side. I've seen it before but didn't know what it was.

So, I put the Americium sample in the castle and let it build up the peaks. Then I replaced the Americium with my Carnotite and watched its familiar peaks build. Then I used the known 59.5 and 609 peaks for calibration and it gave me a bin in the blue at 26.9KeV. I looked that up on my cellphone app "nuclidelib" and found that Americium does indeed have one at 26.3446.!

[Peter-1]

Hello Daryl,
a good idea. I have also tried it immediately and here is my result.

2016_10_19-Am241-10x.png (76.37 KiB) Viewed 7041 times

Peter

[Sesselmann]

Hi Guys,

In the links section of my web site there is a link to the "Lund/LBNL Nuclear Data Search"

http://nucleardata.nuclear.lu.se/toi/

Once you search for an isotope you sometimes get a long confusing list of gamma, but at the bottom of the page is an option to sort the table by intensity (Ig %). This will show the most intense gamma energies first, and it is usually the first two or three you are interested in. Here is the sorted page for Am241 showing the two most intense peaks first.

http://nucleardata.nuclear.lu.se/toi/nu ... =I&sortA=E

Steven

[ZeeCaptain]

Sorry for digging up the old thread...

But shouldn't the 26.3 keV Peak be much smaller? I got a Am-241 Source too. The 26.2 keV peak is 12394 counts and the 59.5 keV peak is 68237. So the main peak is 5.5 times higher than the 26.3 keV one.

I calculated the efficiency for the two energies with my setup. When considering the efficiency i get 187220 decays with 26.3 keV and 509231 decays with an energy of 59.6 keV. But this means, that the 59.6 keV photon is only 2.7 times more likely that one with the energy of 26.3 keV. When looking at the Ig %, this does not make any sense, because it should be something around 15.8 times. (2.4 % vs. 35.9%)

Can somebody please explain why the first peak is that big?

Could this might be more flurescence then the 26.3 keV peak from Am-241?

Felix

[lodovico]

Hi,
with americium 241 you should get the main line at 59 KeV and some peaks between 20 and 25 KeV, more or less. they are the peak of americium at 26 KeV and the XRF peaks of neptunium.
But with uranium ore, like carnotite, you should not have any americium ! So if you find some peaks there, it is likely they are from XRF of lead shielding for example.
Lodovico