NormaliseToMonitor
From MantidProject
Contents |
Summary
Normalises a 2D workspace by a specified monitor spectrum.
Properties
| Order | Name | Direction | Type | Default | Description |
|---|---|---|---|---|---|
| 1 | InputWorkspace | Input | Workspace2D | Mandatory | The name of the input workspace. |
| 2 | OutputWorkspace | Output | Workspace2D | Mandatory | The name to use for the output workspace. |
| 3 | MonitorSpectrum | Input | integer | Optional * | The spectrum number in the InputWorkspace for the monitor spectrum to normalise to. |
| 4 | MonitorWorkspace | Input | MatrixWorkspace | Optional * | A single-spectrum workspace containing the monitor spectrum. |
| 5 | IntegrationRangeMin | Input | double | Optional | The lower bound of the frame range to use. Not used if neither this nor IntegrationRangeMax are set. If only IntegrationRangeMax is set, this property defaults to the frame's minimum value. |
| 6 | IntegrationRangeMax | Input | double | Optional | The upper bound of the frame range to use. Not used if neither this nor IntegrationRangeMin are set. If only IntegrationRangeMin is set, this property defaults to the frame's maximum value. |
* One, and only one, of these properties should be set.
Description
Bin-by-bin mode
In this, the default scenario, each spectrum in the workspace is normalised on a bin-by-bin basis by the monitor spectrum given. The error on the monitor spectrum is taken into account. The normalisation scheme used is:
where si is the signal in a bin, mi the count in the corresponding monitor bin, Δwi the bin width,
| ∑ | mi |
| i |
the integrated monitor count and
| ∑ | Δwi |
| i |
the sum of the monitor bin widths. In words, this means that after normalisation each bin is multiplied by the bin width and the total monitor count integrated over the entire frame, and then divided by the total frame width. This leads to a normalised histogram which has unit of counts, as before.
If the workspace does not have common binning, then the monitor spectrum is rebinned internally to match each data spectrum prior to doing the normalisation.
Normalisation by integrated count mode
This mode is used if one or both of the relevant 'IntegrationRange' optional parameters are set. If either is set to a value outside the workspace range, then it will be reset to the frame minimum or maximum, as appropriate.
The error on the integrated monitor spectrum is taken into account in the normalisation. No adjustment of the overall normalisation takes place, meaning that the output values in the output workspace are technically dimensionless.
Restrictions on the input workspace
The data must be histogram, non-distribution data.
Subalgorithms used
The ExtractSingleSpectrum algorithm is used to pull out the monitor spectrum if it's part of the InputWorkspace. For the 'integrated range' option, the Integration algorithm is used to integrate the monitor spectrum.
In both cases, the Divide algorithm is used to perform the normalisation.
Source Code
Header NormaliseToMonitor.h
Source NormaliseToMonitor.cpp
