Help Na-22 Beta calibration

[THEMuffinMan7]

Hello,

I am working on a project that is attempting to use GM tubes to detect low levels of radiation emitted from food or other objects.

Currently I am trying to find the efficiency of these tubes to beta and gamma radiation. I wanted to get a pure beta and pure gamma source but I was only able to get a Na22 source and a Cs137 source. These both emit beta and gamma. Is it possible to use these to determine the efficeincy of the tubes to beta and gamma separately?

I know I could block the beta with a piece of metal, giving the gamma only, then subtract that from the total to get beta, but how do I calculate how much of each radiation type is being emitted??

Thanks for any help!

 

[Valerie Park]

Yes, it is possible to use these sources to determine the efficiency of the GM tubes for beta and gamma radiation separately. You can calculate the relative amount of beta and gamma emitted from the source by calculating the ratio of the energy of the gamma radiation to the energy of the beta radiation. This can be done using data from the source datasheet or from other reliable sources. Once you have the ratio, you can measure the detection efficiency of the GM tube for each type of radiation and then calculate the overall efficiency of the tube for both types of radiation.