First CS-137 Spectrum

[Svilen]

Hi Steven and Others,

This is what I got from a quite weak CS-137 source - an old spark gap tube. I thought, after all the years, there is not much of the CS left, but it was detectable (I also used a different detector than before). Can you please tell me how do you find this result? Is this performance good enough? How to improve it, except some better shielding maybe (I used a very basic 10mm lead shielding just around the crystal)? Is it possible at all to get sensitivity, high enough to find small amounts of radionuclides like in food for example? Thank you in advance for your comments!
Svilen


The source:



The detector:



The result:

[Sesselmann]

Svilen,

That looks like a good result. Can't tell exactly what resolution it is because you have not selected the region of interest and turned on gaussian correlation, but it would have to be 8% or better.

You have the right kind of detector to do good science so with a bit of fine tuning you should be able to detect Cs137 in samples to within the WHO safe limits. Check out Karl's recent post here; viewtopic.php?f=5&t=261

Steven

[Svilen]

Hi Steven,
Thanks for your answer. The resolution is 7%, here is the picture again, with ROI selected and gaussian correlation turned on:
Unfortunately, I don't have a source with known activity under 1000 Bq/kg, to test the limits of detection, but I hope with this detector I'm getting some good results soon.