Outlook
If only it were that simple! In practice, we often encounter the following characteristics:
- The matrix is not homogeneous. If the matrix consists of (known) homogeneous layers, then the method described above can be used to evaluate each of these layers individually. The sum of the specific activities of a radionuclide in the individual layers then gives the activity of the radionuclide in the entire container. However, if the matrix does not consist of homogeneous layers, then ….
- The radionuclides are not homogeneously distributed. If we can identify point-like distributions of a radionuclide in the spatial distributions, then special evaluation methods can be applied. For other distributions …
- Neither the matrix nor the distribution of the radionuclides is homogeneous. Then we are right at the case “…”
What does “…” mean?
Numerous research and development efforts have addressed the question “what to do when there is no homogeneity.” The result of all this work can be summarized as follows: “Lack of knowledge cannot be replaced by even the most sophisticated mathematical methods.”
Good to know:
The problem of lack of knowledge can be addressed by using complementary measurement methods. For example, the methods of radiography and tomography are mentioned here – but that is another topic.
Thus, our journey to answer the question “what is segmented gamma scanning" has come to an end.
We hope you enjoyed it and now have an idea of what it is about when you next hear someone talking about segmented gamma scanning or read something about it somewhere.
As a “reward” for your perseverance, we can now watch a video of a typical gamma scan measurement. The measurement is a multi-slice scan, where measurements are taken at five height positions. It was recorded at a research institute that also conducts such measurements as part of product control. Throughput is not an issue here, meaning the times spent on a measurement are generally significantly longer than is usual, for example, in a nuclear facility. The video therefore contains sequences in time-lapse mode (duration 5:16 min).
Video of a segmented gamma scan measurement (multi-slice scan, duration: 5:17 min).
Click to start the video.
