Submitted by Anonymous (not verified) on Wed, 2011-03-30 20:51.
Have there been any tests of our tap water. I imagine the water itself blocks radiation. How do you separate radioactive materials from the water you are testing?
This is a good question. Yes, the water shields some of the radiation from our detector but some of it also get's through. Of the radiation particles (these are gamma-ray photons), some of these interact with our detector and even less deposite their entire energy within the detector (some photons just scatter and deposite partial energy). All of this results in some "efficiency" of the photons reaching our detector and deposite the full energy. The full energy is required because the energy of the photon is the "signature" we use to determine if it came from an iodine or cesium atom. We calibrate our system with a known radioactive source with a known concentration in pure deionized water. Once we know the efficiency, we can then determine an unknown concentration in a similar sample by using the number of full energy particles we detect.
Hope that makes sense. These are the types of questions I enjoy answering!
Have there been any tests of
Have there been any tests of our tap water. I imagine the water itself blocks radiation. How do you separate radioactive materials from the water you are testing?
This is a good question.
This is a good question. Yes, the water shields some of the radiation from our detector but some of it also get's through. Of the radiation particles (these are gamma-ray photons), some of these interact with our detector and even less deposite their entire energy within the detector (some photons just scatter and deposite partial energy). All of this results in some "efficiency" of the photons reaching our detector and deposite the full energy. The full energy is required because the energy of the photon is the "signature" we use to determine if it came from an iodine or cesium atom. We calibrate our system with a known radioactive source with a known concentration in pure deionized water. Once we know the efficiency, we can then determine an unknown concentration in a similar sample by using the number of full energy particles we detect.
Hope that makes sense. These are the types of questions I enjoy answering!