PowderDiffILLDetScanReduction v1¶

PowderDiffILLDetScanReduction dialog.

Table of Contents

Summary
Properties
Description
Input Runs
Calibration
Normalisation Options
Output
Workflow
Related Algorithms
Usage
Source

Summary ¶

Performs powder diffraction data reduction for D2B and D20 (when doing a detector scan).

Properties ¶

Name	Direction	Type	Default	Description
Run	Input	list of str lists	Mandatory	File path of run(s). Allowed values: [‘nxs’]
NormaliseTo	Input	string	Monitor	Normalise to monitor, or skip normalisation. Allowed values: [‘None’, ‘Monitor’]
UseCalibratedData	Input	boolean	True	Whether or not to use the calibrated data in the NeXus files.
Output2DTubes	Input	boolean	False	Output a 2D workspace of height along tube against tube scattering angle.
Output2D	Input	boolean	False	Output a 2D workspace of height along tube against the real scattering angle.
Output1D	Input	boolean	True	Output a 1D workspace with counts against scattering angle.
HeightRange	Input	dbl list		A pair of values, comma separated, to give the minimum and maximum height range (in m). If not specified the full height range is used.
OutputWorkspace	Output	WorkspaceGroup	Mandatory	Output workspace containing the reduced data.

Description ¶

This algorithm performs the data reduction for the D2B instrument at the ILL, and also for D20 when doing a detector scan.

Provide the list of the input runs, that is the runs corresponding to a single detector scan, following the syntax in MultipleFileProperty. For specifying multiple runs it is best to use : as the separator - e.g. 508093:508095. Using - is also possible, this will call MergeRuns, but there is a performance penalty for this.

Calibration ¶

The NeXus files for D2B contain raw data and pre-calibrated data. Either of these can be used when loading.

Normalisation Options ¶

The default is for normalisation to monitor, but this can be skipped.

Output ¶

The output from the algorithm is a WorkspaceGroup, containing the requested outputs:

Output2DTubes - Outputs a 2D workspace of tube height against scattering angle. In other words with no correction for Debye-Scherrer cones. It is expected that this is only used for checking alignment.
Output2D - Outputs a 2D workspace of height along tube against scattering angle for pixel in tube. Here there is effectively a correction for the Debye-Scherrer cones.
Output1D - Outputs a 1D workspace of counts against scattering angle. The vertical integration range for this is set in the HeightRange option.

Note for D20 only the Output1D option will be relevant.

For Output2DTubes only the negative scattering angles are included, they are excluded for Output2D and Output1D.

Use SaveFocusedXYE to save in FullProf format #10, or SaveGSS for GSAS format.

Workflow ¶

../_images/PowderDiffILLDetScanReduction-v1_wkflw.png

Usage ¶

Example - PowderDiffDetScanILLReduction

red_ws = PowderDiffILLDetScanReduction(Run='508093:508095', Output2DTubes=True, Output2D=True, Output1D=True)
print("'2DTubes' output workspace has {0} diffractograms having {1} bins each".format(red_ws[0].getNumberHistograms(), red_ws[0].blocksize()))
print("'2D' output workspace has {0} diffractograms having {1} bins each".format(red_ws[1].getNumberHistograms(), red_ws[1].blocksize()))
print("'1D' output workspace has {0} diffractograms having {1} bins each".format(red_ws[2].getNumberHistograms(), red_ws[2].blocksize()))

Output:

'2DTubes' output workspace has 128 diffractograms having 3250 bins each
'2D' output workspace has 128 diffractograms having 3025 bins each
'1D' output workspace has 1 diffractograms having 3025 bins each

Categories: Algorithms | ILL\Diffraction | Diffraction\Reduction

Source ¶

Python: PowderDiffILLDetScanReduction.py (last modified: 2018-03-07)