Generating elemental maps from raw XRF data using the Sort EVT window
You will need to first import and fit your raw data, and generate a DA matrix, before processing the raw data in the Sort EVT window.
Video
Coming soon!
Steps
1. In the Sort EVT window, load a recent .dai file. We usually dont start from scratch- this way we avoid setting detector parameters specific to the Maia every single time.
2. Change the path for the "First File" to the ".0" blog file in your raw directory for the data you wish to analyze.
- GeoPIXE may ask:
Do you want to set the detector calibration parameters based on the values loaded along with the list-mode header? Respond NO. We will set the energy calibration ourselves, as it could likely different from what was used to collect the data
- GeoPIXE may ask:
Do you want to use these to set the "Pileup" and "Throttle" fileds? Respond YES, these paths are saved with the raw data and we want them to match what we used to collect the data
3. Change the path for the "Last File" to be the last file in your raw data set.
4. Change the output path. Make sure it points to a location in your analysis directory.
5. You do not have to change any parameters in the "Device" tab.
6. You normally do not have to change any parameters in the "Scan" tab. If you want to crop your final image, however, you should change "Image Mode" from "Image full area" to "Image select sub-region (no XY compression)" and set the XY origin and cropped area size in the resulting fields.
7. In the "Flux" tab, make sure the IC Scaler channel, Preamp sensitivity, and Preamp scale are correct. Check the dwell time, and make sure Q/IC (
the flux/charge conversion) is correct for your scan. You don't need to change the Equivalent charge box.
8. In the "DA/E.Cal" tab:
- Click Get, then load the energy calibration you used in your spectrum (probably in the setup folder).
- Click File, and load the DA matrix you wish to use as the model to analyze your data.
9. Turn on cluster, if desired, and press Start. A progress bar should appear, and when complete, your elemental concentration maps should automatically load in the main GeoPIXE window. Sometimes the cluster option is finicky, so if the progress bar does not appear, or appears quickly but no image loads in the main window, try turning off the cluster option and try again.
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LouisaSmieska - 10 May 2016