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SANSBeamFluxCorrection v1

Summary

Performs beam flux correction on TOF SANS data.

See Also

SANSSolidAngleCorrection

Properties

Name	Direction	Type	Default	Description
InputWorkspace	Input	MatrixWorkspace	Mandatory	Workspace to be corrected
InputMonitorWorkspace	Input	MatrixWorkspace	Mandatory	Workspace containing the monitor counts for the sample data
ReferenceFluxFilename	Input	string	Mandatory	File containing the reference flux spectrum. Allowed extensions: [‘_event.nxs’, ‘.nxs’, ‘.nxs.h5’]
ReductionProperties	Input	string	__sans_reduction_properties
OutputWorkspace	Output	MatrixWorkspace	Mandatory	Corrected workspace.
OutputMessage	Output	string

Description

Performs beam flux correction for TOF SANS data.

The correction goes as follows:

\(I({\lambda}) = I_0({\lambda}) / \Phi_{sample}\)

where

\(\Phi_{sample} = \frac{M_{sample}}{M_{ref}} \Phi_{ref}\)

Workflow

Usage

Example - Performing a Beam Flux Correction on Dummy Data

# Create some dummy data, as well as a dummy monitor ws for EQSANS.
x = [1,2,3,4,5,6,7,8,9,10,11]
y = 491520*[0.1]
ws = CreateWorkspace(DataX=x,DataY=y,DataE=y,NSpec='49152',UnitX='Wavelength')
LoadInstrument(ws, InstrumentName="EQSANS", RewriteSpectraMap=True)
monitor = SumSpectra(ws)

# Do the correction, dragging in the file which contains the reference flux spectrum.
corrected = SANSBeamFluxCorrection(ws, InputMonitorWorkspace=monitor, ReferenceFluxFilename="SANSBeamFluxCorrectionMonitor.nxs")

print("The expected value of each bin should be {:.11e}.".format(0.1/(49152*0.1)/(49152*0.1)))
print("The actual value of the first bin is {:.11e}.".format(corrected[0].readY(0)[0]))

Output:

The expected value of each bin should be 4.13921144274e-09.
The actual value of the first bin is 4.13921144273e-09.

Categories: AlgorithmIndex | Workflow\SANS\UsesPropertyManager | CorrectionFunctions\InstrumentCorrections

Source

C++ header: SANSBeamFluxCorrection.h

C++ source: SANSBeamFluxCorrection.cpp