3.5

EQSANSDarkCurrentSubtraction v1

../_images/EQSANSDarkCurrentSubtraction-v1_dlg.png

EQSANSDarkCurrentSubtraction dialog.

Table of Contents

Summary

Perform EQSANS dark current subtraction.

Properties

Name Direction Type Default Description
InputWorkspace Input MatrixWorkspace Mandatory  
Filename Input string Mandatory The name of the input event Nexus file to load as dark current. Allowed extensions: [‘_event.nxs’]
OutputWorkspace Output MatrixWorkspace Mandatory  
PersistentCorrection Input boolean True If true, the algorithm will be persistent and re-used when other data sets are processed
ReductionProperties Input string __sans_reduction_properties  
OutputDarkCurrentWorkspace Output MatrixWorkspace    
OutputMessage Output string    

Description

Subtract the dark current from an EQSANS data set. This algorithm is rarely called directly. It is called by SANSReduction.

This workflow algorithm will:

  • Properly load the dark current data set
  • Normalize the dark current to the data taking period
  • Subtract the dark current from the input workspace

The dark current is subtracted pixel by pixel by normalizing the dark current data by counting time, as follows:

I'(x,y)=I_{data}(x,y)-\frac{T_{data}}{T_{dc}} I_{dc}(x,y)

where the T-values are the counting times for the data set and the dark current (dc).

The example above uses the counting time for normalization. If the proton charge is available, the normalization will be done using the proton charge instead.

Categories: Algorithms | Workflow | SANS | UsesPropertyManager