Hello, all!
I have been successfully measuring F in apatite up until today, when I 'improved' several of my standard bundles by finally going off and collecting high-count peak shape references. Now, even when I assign a F standard and x-ray line in the Quant Alien, the element just vanishes from the final results. I don't know how adding non-auto shape references would do this, but it is the only thing I can think of that changed. Many of the other standard bundles I 'improved' at the same time still give good results.
What would cause DTSAII to exclude a specified element in the results?
Can you send me some files (nicholas.ritchie@nist.gov) and I'll take a look.
I'll need:
- The standard spectra - as bundles if that is what you are using
- An unknown or two
- The detector definition
The detector definition can be exported from the "File" => "Preferences" menu item. Select the detector in the tree view and scroll to the bottom of the detector definition page. There is an "Export detector" button that will export an .xdet file.
I think the problem is that some of the files used as references have peak interferences and are not suitable.
To make this less likely, I've made an improvement to the Standard Bundler. The Standard Bundler will now check the files specified as references to ensure that they are suitable and warn if they are not.
In addition, the improved Standard Bunder, has a new tool that performs a statistical comparison to score the standard files (it is encouraged to collect multiple replicas of the standard) to determine which are most similar and to permit dropping outliers.
The workflow that I use to ensure that Standard Bundles will work is:
- Quantify the spectra I plan to use as standards using the references.
- I check the residual and the quantification results to ensure that they look reasonable.
- I use the Standard Bundler to aggregate multiple replica of the standard spectra into a single standard. (Usually, I collect five 60 s spectra rather than one 300 s spectrum.) I specify the references that I verified in the previous step.
- Finally, I test the standards that I just created to quantify the raw standard spectra. The quant results should replicate the known composition to within statistical scatter.
A pre-release version is available at https://drive.google.com/file/d/17YAXRYkQ9vAQ509AwP5eZagdGfShX-dE/view?usp=sharing (https://drive.google.com/file/d/17YAXRYkQ9vAQ509AwP5eZagdGfShX-dE/view?usp=sharing). Feedback is welcome.
You'll find a video describing the improved Standard Bundler on YouTube (https://www.youtube.com/watch?v=V7-srnvU5SE)