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SimpleShapeMonteCarloAbsorption v1

Summary

Calculates absorption corrections for a given sample shape.

See Also

CalculateMonteCarloAbsorption, MonteCarloAbsorption

Properties

Name	Direction	Type	Default	Description
InputWorkspace	Input	MatrixWorkspace	Mandatory	Input workspace
MaterialAlreadyDefined	Input	boolean	False	Select this option if the material has already been defined
ChemicalFormula	Input	string		Chemical formula of sample
CoherentXSection	Input	number	Optional	The coherent cross section of the sample in barns. It can be used instead of theChemical Formula.
IncoherentXSection	Input	number	Optional	The incoherent cross section of the sample in barns. It can be used instead of theChemical Formula.
AttenuationXSection	Input	number	Optional	The absorption cross section of the sample in barns. It can be used instead of theChemical Formula.
DensityType	Input	string	Mass Density	Use of Mass density or Number density. Allowed values: [‘Mass Density’, ‘Number Density’]
Density	Input	number	0.1	The value for the Mass density (g/cm^3) or Number density (1/Angstrom^3).
NumberDensityUnit	Input	string	Atoms	Choose which units Density refers to. Allowed values: [Atoms, Formula Units]. Allowed values: [‘Atoms’, ‘Formula Units’]
NumberOfWavelengthPoints	Input	number	10	Number of wavelengths for calculation
EventsPerPoint	Input	number	1000	Number of neutron events
Interpolation	Input	string	Linear	Type of interpolation. Allowed values: [‘Linear’, ‘CSpline’]
MaxScatterPtAttempts	Input	number	5000	Maximum number of tries made to generate a scattering point
BeamHeight	Input	number	1	Height of the beam (cm)
BeamWidth	Input	number	1	Width of the beam (cm)
Shape	Input	string	FlatPlate	Geometry of sample environment. Options are: FlatPlate, Cylinder, Annulus. Allowed values: [‘FlatPlate’, ‘Cylinder’, ‘Annulus’]
Height	Input	number	0	Height of the sample environment (cm)
Width	Input	number	0	Width of the FlatPlate sample environment (cm)
Thickness	Input	number	0	Thickness of the FlatPlate sample environment (cm)
Center	Input	number	0	Center of the FlatPlate sample environment
Angle	Input	number	0	Angle of the FlatPlate sample environment with respect to the beam (degrees)
Radius	Input	number	0	Radius of the Cylinder sample environment (cm)
OuterRadius	Input	number	0	Outer radius of the Annulus sample environment (cm)
InnerRadius	Input	number	0	Inner radius of the Annulus sample environment (cm)
OutputWorkspace	Output	MatrixWorkspace	Mandatory	The output corrected workspace.

Warning

This algorithm is deprecated in favour of PaalmanPingsMonteCarloAbsorption.

Description

Sets up a sample shape, along with the required material properties, and runs the MonteCarloAbsorption algorithm. This algorithm merely serves as a simpler interface to define the shape & material of the sample without having to resort to the more complex CreateSampleShape & SetSampleMaterial algorithms. The computational part is all taken care of by MonteCarloAbsorption. Please see that documentation for more details. Currently the shape geometries supported are:

• Flat Plate

• Cylinder

• Annulus

Workflow

Usage

Example

qens_ws = CreateSampleWorkspace(Function="Quasielastic",
                                XUnit="Wavelength",
                                XMin=-0.5,
                                XMax=0.5,
                                BinWidth=0.01)

corrected = SimpleShapeMonteCarloAbsorption(InputWorkspace = qens_ws,
                                            ChemicalFormula = 'H2-O',
                                            DensityType = 'Mass Density',
                                            Density = 1.0,
                                            EventsPerPoint = 200,
                                            BeamHeight = 3.5,
                                            BeamWidth = 4.0,
                                            Height = 2.0,
                                            Shape = 'FlatPlate',
                                            Width = 1.4,
                                            Thickness = 2.1)

print("y-axis label: {}".format(corrected.YUnitLabel()))

Output:

y-axis label: Attenuation factor

Categories: AlgorithmIndex | Workflow\Inelastic | CorrectionFunctions\AbsorptionCorrections | Workflow\MIDAS

Source

Python: SimpleShapeMonteCarloAbsorption.py