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EQSANSDarkCurrentSubtraction dialog.
Table of Contents
| 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 |
Subtract the dark current from an EQSANS data set. This algorithm is rarely called directly. It is called by SANSReduction.
This workflow algorithm will:
The dark current is subtracted pixel by pixel by normalizing the dark current data by counting time. The total number of dark current counts \(N_{dc}(i)\) for each pixel i is obtained by integrating over all time of flight bins. For a given pixel and wavelength bin, the corrected signal is given by:
\(I'(i,\lambda_j)=I_{data}(i,\lambda_j)-N_{dc}(i) \ \ \frac{T_{data}}{T_{dc}} \ \ \frac{t_{frame}-t^{low}_{cut} - t^{high}_{cut}}{t_{frame}} \ \ \frac{\Delta\lambda_j}{\lambda_{max}-\lambda_{min}}\)
where the T-values are the counting times for the data set and the dark current (dc). The \(t_{cut}\) values are the TOF cuts at the beginning and end of a frame. \(t_{frame}\) is the width of a frame. \(\Delta\lambda_j\) is the width of the wavelength bin we are considering.
Categories: AlgorithmIndex | Workflow\SANS\UsesPropertyManager
C++ header: EQSANSDarkCurrentSubtraction2.h (last modified: 2020-03-20)
C++ source: EQSANSDarkCurrentSubtraction2.cpp (last modified: 2020-04-07)