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MDNormSCDPreprocessIncoherent v1

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Summary

Creates the Solid Angle and Flux workspace from an incoherent scatterer for MDNormSCD

See Also

MDNormSCD, MDNormDirectSC

Properties

Name	Direction	Type	Default	Description
Filename	Input	list of str lists	Mandatory	Files to combine in reduction. Allowed extensions: [‘_event.nxs’, ‘.nxs.h5’, ‘.nxs’]
Background	Input	string		Background run. Allowed extensions: [‘_event.nxs’, ‘.nxs.h5’, ‘.nxs’]
BackgroundScale	Input	number	1	The background will be scaled by this number before being subtracted.
FilterByTofMin	Input	number	Optional	Optional: To exclude events that do not fall within a range of times-of-flight. This is the minimum accepted value in microseconds. Keep blank to load all events.
FilterByTofMax	Input	number	Optional	Optional: To exclude events that do not fall within a range of times-of-flight. This is the maximum accepted value in microseconds. Keep blank to load all events.
MomentumMin	Input	number	Mandatory	Minimum value in momentum.
MomentumMax	Input	number	Mandatory	Maximum value in momentum.
GroupingFile	Input	string		A file that consists of lists of spectra numbers to group. See GroupDetectors. Allowed extensions: [‘.xml’, ‘.map’]
NormaliseByCurrent	Input	boolean	True	Normalise the Solid Angle workspace by the proton charge.
LoadInstrument	Input	string		Load a different instrument IDF onto the data from a file. See LoadInstrument. Allowed extensions: [‘.xml’]
DetCal	Input	string		Load an ISAW DetCal calibration onto the data from a file. See LoadIsawDetCal. Allowed extensions: [‘.detcal’]
MaskFile	Input	string		Masking file for masking. Supported file format is XML and ISIS ASCII. See LoadMask. Allowed extensions: [‘.xml’, ‘.msk’]
SphericalAbsorptionCorrection	Input	boolean	False	Apply Spherical Absorption correction using AnvredCorrection
LinearScatteringCoef	Input	number	Optional	Linear scattering coefficient in 1/cm. If not provided this will be calculated from the material cross-section if present (set with SetSampleMaterial)
LinearAbsorptionCoef	Input	number	Optional	Linear absorption coefficient at 1.8 Angstroms in 1/cm. If not provided this will be calculated from the material cross-section if present (set with SetSampleMaterial)
Radius	Input	number	Optional	Radius of the sample in centimeters. f not provided the radius will be taken from the sample shape if it is a sphere (set with SetSample).
SolidAngleOutputWorkspace	Output	Workspace	Mandatory	Output Workspace for Solid Angle
FluxOutputWorkspace	Output	Workspace	Mandatory	Output Workspace for Flux

Description

This algorithm preprocesses an incoherent scattering sample (usually Vanadium) for use with MDNormSCD. The input filename follows the syntax from MultipleFileProperty. The resulting workspaces can be saved with SaveNexus.

Usage

Corelli example using multiple files with masking

# Create a simple mask file
MaskFilename=mantid.config.getString("defaultsave.directory")+"MDNormSCDPreprocessIncoherent_mask.xml"
LoadEmptyInstrument(InstrumentName='CORELLI', OutputWorkspace='CORELLI')
# Missing banks
MaskBTP('CORELLI', Bank='1-6,29,30,62,63-68,91')
# End of tubes
MaskBTP('CORELLI', Pixel='1-15,242-256')
SaveMask('CORELLI', MaskFilename)

SA, Flux = MDNormSCDPreprocessIncoherent(Filename='CORELLI_28119-28123',
                                         MomentumMin=2.5,
                                         MomentumMax=10,
                                         MaskFile=MaskFilename)

Solid Angle instrument view:

Flux spectrum plot:

TOPAZ example with backgound subtraction, grouping, masking and Spherical Absorption Correction

SA, Flux = MDNormSCDPreprocessIncoherent(Filename='TOPAZ_15670',
                                         Background='TOPAZ_15671',
                                         FilterByTofMin=500,
                                         FilterByTofMax=16000,
                                         MomentumMin=1.8,
                                         MomentumMax=12.5,
                                         GroupingFile='/SNS/TOPAZ/IPTS-15376/shared/calibration/TOPAZ_grouping_2016A.xml',
                                         DetCal='/SNS/TOPAZ/IPTS-15376/shared/calibration/TOPAZ_2016A.DetCal',
                                         MaskFile='/SNS/TOPAZ/IPTS-15376/shared/calibration/TOPAZ_masking_2016A.xml',
                                         SphericalAbsorptionCorrection=True,
                                         LinearScatteringCoef=0.367,
                                         LinearAbsorptionCoef=0.366,
                                         Radius=0.2)
print(SA.getNumberHistograms())
print(SA.blocksize())
print(Flux.getNumberHistograms())
print(Flux.blocksize())

Output:

1507328
1
23
10000

Related Algorithms

MDNormSCD uses the output of this algorithm

Categories: AlgorithmIndex | MDAlgorithms\Normalisation

Source

Python: MDNormSCDPreprocessIncoherent.py