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Experimental Details and Auto-Processing Steps for I15-1 Data

Experimental Details and Auto-Processing Steps for I15-1 Data

You have now analysed your data and looking to publish, here are some details that you may want to include in your experimental section as well as your acknowledgments.

Experimental

Detector Used:

Perkin-Elmer (Varex) XRD 4343CT: https://www.vareximaging.com/wp-content/uploads/2022/01/XRD-4343CT_118914-1.pdf

Sample-to-detector distance:

This can vary from sample to sample, but the exact calibrated distance can be found in your .nxs file. Simply load the RAW .nxs file (this is the file in the top directory labeled i15-1-12345.nxs) into DAWN’s DataVis tab. Right click the file to open tree, the distance will be found: entry > intrument > pe2AD > distance, as shown below.

image-20251003-124354.png

Beam Size:

We typically operate at a size of 700 μm (h) x 150 μm (v) at the beam position. The vertical will be reduced for DRIX style experiments to approximately 10 μm. Beam size is not typically measured experiment to experiment, so please contact your beamline scientist if you need accurate measurements.

Calibration Standards

Any experiment conducted on the beamline will have been calibrated in one or more ways, the standards are as follows:

Silicon 640d/g - Detector Calibrations

Si/Al2O3 - High Temperature External Calibrant

Pb - Low Temperature External Calibrant

Data Corrections

Your xy processed 1D data will have been automatically processed via our DAWN pipelines, allowing for confidence and repeatability in data. To examine these or reporcess data, simply drag a processed data file (i15-1-12345-pe2AD-1234abcd-1a2b____.bragg.nxs) into the Processing tab in DAWN. It should look something like this:

image-20251003-125121.png

The general processes it will undergo are:

  1. Import Detector Calibration - Apply the detector calibration that your beamline scientist will have created.

  2. Multiply Frame - Applies the flatfield correction

  3. Powder Diffraction Intensity Corrections - Correct for transmission and polarisation.

  4. Import Mask From File - Import masks that mask out dead pixels and detector edges.

  5. Mask by coordinate/Mask Outside Region - Masks out the lower right hand corner and detector defects.

  6. Mask Outliers in Q - Masks out hot pixels.

  7. Azimuthal Integration - Integrates the data into 1D over a range of 0.0 - 38.4 degrees.

  8. Export to Text File - Creates a standard .xy file of the above integration.

  9. Divide - Divides through by the i0, normalising the data against the ring current.

  10. Export to Text File - Creates an _norm.xy file containing the normalised data.