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SANSILLMultiProcess v1¶

Summary ¶

Performs SANS data reduction of the entire experiment.

Properties ¶

Name	Direction	Type	Default	Description
SampleRunsD1	Input	list of str lists		Sample run(s) at the distance #1. Allowed values: [‘nxs’]
SampleRunsD2	Input	list of str lists		Sample run(s) at the distance #2. Allowed values: [‘nxs’]
SampleRunsD3	Input	list of str lists		Sample run(s) at the distance #3. Allowed values: [‘nxs’]
SampleRunsD4	Input	list of str lists		Sample run(s) at the distance #4. Allowed values: [‘nxs’]
SampleRunsD5	Input	list of str lists		Sample run(s) at the distance #5. Allowed values: [‘nxs’]
DarkCurrentRuns	Input	list of str lists		Absorber (Cd/B4C) run(s). Allowed values: [‘nxs’]
EmptyBeamRuns	Input	list of str lists		Empty beam run(s). Allowed values: [‘nxs’]
FluxRuns	Input	list of str lists		Empty beam run(s) for flux calculation only; if left blank the flux will be calculated from EmptyBeamRuns. Allowed values: [‘nxs’]
EmptyContainerRuns	Input	list of str lists		Empty container run(s). Allowed values: [‘nxs’]
SampleTrRunsW1	Input	list of str lists		Sample transmission run(s) at the wavelength #1. Allowed values: [‘nxs’]
SampleTrRunsW2	Input	list of str lists		Sample transmission run(s) at the wavelength #2. Allowed values: [‘nxs’]
TrDarkCurrentRuns	Input	list of str lists		Absorber (Cd/B4C) run(s) for transmission calculation. Allowed values: [‘nxs’]
ContainerTrRuns	Input	list of str lists		Container transmission run(s). Allowed values: [‘nxs’]
TrEmptyBeamRuns	Input	list of str lists		Empty beam run(s) for transmission calculation. Allowed values: [‘nxs’]
SensitivityMap	Input	string		File or workspace containing the map of the relative detector efficiencies.
DefaultMask	Input	string		File or workspace containing the default mask (detector edges and dead pixels/tubes) to be applied to all the detector configurations.
BeamStopMasks	Input	string		File(s) or workspace(s) containing the detector mask per distance configuration (typically beam stop).
FlatFields	Input	string		File(s) or workspaces containing the reduced water data (in 2D) for absolute normalisation.
Solvents	Input	string		File(s) or workspace(s) containing the reduced solvent/buffer data (in 2D) for solvent subtraction.
TransmissionThetaDependent	Input	boolean	True	Whether or not to apply the transmission correction in 2theta-dependent way.
NormaliseBy	Input	string	Monitor	Allowed values: [‘None’, ‘Time’, ‘Monitor’]
TrBeamRadius	Input	dbl list	0.1	Beam radius [m] used for transmission and flux calculations.
BeamRadius	Input	dbl list	0.25	Beam radius [m] used for beam center search.
SampleThickness	Input	dbl list	0.1	Sample thickness [cm] used in final normalisation.
SampleThicknessFrom	Input	string	User	Define where to read the sample thicknesses from. Allowed values: [‘User’, ‘Nexus’]
SampleNames	Input	str list		Sample names to put in the axis of the output workspaces.
SampleNamesFrom	Input	string	RunNumber	Define where to read the sample names from. Allowed values: [‘User’, ‘Nexus’, ‘RunNumber’]
WaterCrossSection	Input	number	1	Provide the water cross-section; used only if the absolute scale is done by dividing to water.
ProduceSensitivity	Input	boolean	False	Whether or not to produce a sensitivity map; should be used for water reduction only.
SensitivityWithOffsets	Input	boolean	False	Whether the sensitivity data has been measured with different horizontal offsets (D22 only).
MinThreshold	Input	number	0	Minimum threshold for calculated sensitivity.
MaxThreshold	Input	number	2	Maximum threshold for calculated sensitivity.
DistancesAtWavelength2	Input	long list		Defines which distance indices (starting from 0) match to the 2nd wavelength
OutputBinning	Input	string		Output binning for each distance( : separated list of binning params).
OutputType	Input	string	I(Q)	Final integration type; at the moment only I(Q) is supported. Allowed values: [‘I(Q)’]
CalculateResolution	Input	string	None	Choose to calculate the Q resolution. Allowed values: [‘MildnerCarpenter’, ‘DirectBeam’, ‘None’]
DefaultQBinning	Input	string	PixelSizeBased	Choose how to calculate the default Q binning. Allowed values: [‘PixelSizeBased’, ‘ResolutionBased’]
BinningFactor	Input	number	1	Specify a multiplicative factor for default Q binning (pixel or resolution based).
NumberOfWedges	Input	number	0	Number of wedges to integrate separately.
WedgeAngle	Input	number	30	Wedge opening angle [degrees].
WedgeOffset	Input	number	0	Wedge offset angle from x+ axis.
AsymmetricWedges	Input	boolean	False	Whether to have asymmetric wedges.
WavelengthRange	Input	dbl list	1,10	Wavelength range [Angstrom] to be used in integration (TOF only).
ShapeTable	Input	TableWorkspace		The name of the table workspace containing drawn shapes on which to integrate. If provided, NumberOfWedges, WedgeOffset and WedgeAngle arguments are ignored.
OutputPanels	Input	boolean	False	Output I(Q) per detector bank.
PerformStitching	Input	boolean	True	Wheter or not to perform stitching.
ManualScaleFactors	Input	dbl list		Manually specified scale factors, must follow the same order of the workspaces in the list.
TieScaleFactors	Input	boolean	False	Whether or not to calculate a single scale factor per workspace for all the spectra.
ScaleFactorCalculation	Input	string	MedianOfRatios	Allowed values: [‘MedianOfRatios’, ‘Manual’]
StitchReferenceIndex	Input	number	1	The index of the reference workspace during stitching, by default the middle distance will be chosen as reference if there are 3.
OutputWorkspace	Output	WorkspaceGroup	Mandatory	The output workspace group containing the reduced data.

This algorithms performs complete treatment of SANS data recorded with the ILL instruments. This high level algorithm steers the reduction for multiple samples measured with one or more detector distances in the most optimal way. The sample measurements will be corrected for all the instrumental effects and converted to Q-space, producing by default the azimuthal average curve \(I(Q)\). Optionally, it can also perform anisotropic integration with azimuthal wedges or hand-drawn sectors in the instrument viewer. If requested, it can also produce separate \(I(Q)\) curves per detector panel. Note, that panels and azimuthal wedges cannot be requested simultaneously. The algorithm supports monochromatic (standard, kinetic, and event) as well as TOF modes (linear or variable binning, D33 only). Makes use of SANSILLReduction and SANSILLIntegration and the algorithm suite used therein.

Output ¶

The algorithm will generate a workspace group with the name as provided in the mandatory parameter OutputWorkspace. The group will contain many workspaces as follows:

The corrected real-space workspaces (2D), one per detector distance
The integrated I(Q) workspace, one per detector distance
Optionally, the I(Q) workspaces per azimuthal sector or per detector panel, if requested
The stitched I(Q) workspace (also for wedges, if requested)
The calculated scale factors for stitching
The transmission workspaces, one per wavelength

Notes ¶

The algorithm will cache the reduced calibration measurements (empty beams, dark currents, empty containers, etc.) in the ADS. This is to ensure that subsequent runs with the same calibrants run faster. However, if a critical parameter is changed, such as the normalisation option, those workspaces must be manually cleared before processing again.
The sample runs for different distances must be filled in order; that is, if there is only one distance is present, they must be filled in D1, if only 2, then D1 and D2, and so on.
The transmission runs for different wavelengths must be filled in order; that is, if there is only one wavelength, they must be filled in W1, if 2, then W1 and W2.
See the section in SANSILLReduction regarding the blank samples and transmission replicae.

Workflow ¶

Below is the high level flowchart of the algorithm. It calculates transmissions (up to 2 wavelengths), then proceeds to the reduction of sample runs (up to 5 distances). At each distance, it will load all the samples, concatenate them and then pass through the reduction steps up to azimuthal averaging. Finally, the I(Q) curves obtained per distance, will be stitched.