4.2

ApplyMuonDetectorGroupPairing v1

../_images/ApplyMuonDetectorGroupPairing-v1_dlg.png

ApplyMuonDetectorGroupPairing dialog.

Summary

Perform an asymmetry analysis on two groupings of muon detectors.

Properties

Name Direction Type Default Description
InputWorkspaceGroup InOut WorkspaceGroup Mandatory The workspace group to which the output will be added.
PairName Input string   The name of the pair. Must contain at least one alphanumeric character.
Alpha Input number 1 Alpha parameter used in the asymmetry calculation.
SpecifyGroupsManually Input boolean False Specify the pair of groups manually using the raw data and various optional parameters.
InputWorkspace1 Input MatrixWorkspace   Input workspace containing data from grouped detectors.
InputWorkspace2 Input MatrixWorkspace   Input workspace containing data from grouped detectors.
InputWorkspace Input Workspace   Input workspace containing data from detectors which are to be grouped.
Group1 Input string 1 The grouping of detectors, comma separated list of detector IDs or hyphenated ranges of IDs.
Group2 Input string 1 The grouping of detectors, comma separated list of detector IDs or hyphenated ranges of IDs.
TimeMin Input number 0.1 Start time for the data in micro seconds. Only used with the asymmetry analysis.
TimeMax Input number 32 End time for the data in micro seconds. Only used with the asymmetry analysis.
RebinArgs Input string   Rebin arguments. No rebinning if left empty.
TimeOffset Input number 0 Shift the times of all data by a fixed amount. The value given corresponds to the bin that will become time 0.0.
SummedPeriods Input string 1 A list of periods to sum in multiperiod data.
SubtractedPeriods Input string   A list of periods to subtract in multiperiod data.
ApplyDeadTimeCorrection Input boolean False Whether dead time correction should be applied to input workspace
DeadTimeTable Input TableWorkspace   Table with dead time information. Must be specified if ApplyDeadTimeCorrection is set true.

Description

The algorithm is essentially a wrapper around the MuonProcess v1 algorithm, performing an asymmetry calculation on a pair of groups of detectors. These groups may be specified manually, allowing various processing options such as rebinning and dead time correction, or alternatively the algorithm accepts two workspaces which are assumed to contain the processed groups as a single spectra.

The result of the calculation are stored in the provided WorkspaceGroup using a unique name.

Analysis

This algorithm performs the PairAsymmetry option of the MuonProcess v1 algorithm, requiring two items of data; spectra corresponding to the groups of detector IDs. This can be given directly to the algorithm via the InputWorkspace1 and InputWorkspace2 properties, which accept MatrixWorkspaces with single spectra and identical binning. The pair asymmetry is calculated between the times TimeMin and TimeMax, and using the Alpha parameter (see CalculateMuonAsymmetry v1 for details).

Alternatively by checking setting SpecifyGroupsManually to true the groupings can be performed as part of the algorithm (requiring the full, ungrouped, data in InputWorkspace).

In this case Group1 and Group2 are separator or range based lists (e.g. “1,2,3-6,7”) of detector IDs.

Rebbing is optional and can be achieved through the Rebin property (using syntax as in Rebin v1).

The way in which multi period data is combined before the analysis is determined by SummedPeriods and SubtractedPeriods. For example, setting SummedPeriods to “1,2” and SubtractedPeriods to “3,4” would result in the period spectra being combined in the form (1+2)-(3+4).

Note that the action of SummedPeriods and SubtractedPeriods is performed before the asymmetry analysis.

The workspaces which hold the analysed data are stored in the WorkspaceGroup, using a unique name. As an example, from the following variables :

  1. The InputWorkspaceGroup name is “inputGroup”
  2. PairName is “test”
  3. SummedPeriods is “1,2”
  4. SubtractedPeriods is “3,4”

then the name would be “inputGroup; Pair; test; Asym; 1+2-3+4; #1”. A second workspace is also created with the same name, but ending in “#1_Raw”, the only difference being that the RebinArgs are not applied to the latter workspace. For single period data the name would instead be “inputGroup; Pair; test; Asym; #1”.

An option exists to apply dead time correction to the counts if ApplyDeadTimeCorrection is true, requiring a DeadTimeTable with the format as in ApplyDeadTimeCorr v1.

The TimeOffset parameter shifts the time axis to start at the given time (all bins are offset by the value). In MuonProcess v1 this is equivalent to LoadedTimeZero - TimeZero. Note that the TimeMin and TimeMax refer to the values before the offset is applied.

Usage

Note

To run these usage examples please first download the usage data, and add these to your path. In MantidPlot this is done using Manage User Directories.

Note

For examples of applying custom dead times, please refer to ApplyDeadTimeCorr v1 documentation.

For examples of applying custom grouping, please refer to MuonGroupDetectors v1 documentation.

For examples of applying custom rebinning, please refer to Rebin v1 documentation.

Example - Pair asymmetry for MUSR run:

# Clear the ADS before starting
AnalysisDataService.clear()

# Create the workspace group in which the analysed workspaces will be placed
ws = CreateSampleWorkspace()
wsGroup = GroupWorkspaces("ws")
RenameWorkspace(
                  InputWorkspace="wsGroup",
                  OutputWorkspace='MUSR00015193',
                  OverwriteExisting=True)

# Load the data
LoadMuonNexus(  Filename='MUSR00015193.nxs',
                OutputWorkspace='MuonAnalysis')

# Create two detector groupings
ApplyMuonDetectorGrouping(
    InputWorkspace='MuonAnalysis',
    InputWorkspaceGroup='MUSR00015193',
    GroupName='fwd',
    Grouping='1-32'
    )
ApplyMuonDetectorGrouping(
    InputWorkspace='MuonAnalysis',
    InputWorkspaceGroup='MUSR00015193',
    GroupName='bwd',
    Grouping='33-64'
    )
# Add the groupings to the group workspace
wsGroup.add('MUSR00015193; Group; fwd; Counts; #1_Raw')
wsGroup.add('MUSR00015193; Group; bwd; Counts; #1_Raw')

# Apply the pairing algorithm to the two groups
ApplyMuonDetectorGroupPairing(
       InputWorkspaceGroup='MUSR00015193',
       PairName='pairTest',
       Alpha=1.0,
       SpecifyGroupsManually=False,
       InputWorkspace1='MUSR00015193; Group; fwd; Counts; #1_Raw',
       InputWorkspace2='MUSR00015193; Group; bwd; Counts; #1_Raw'
       )

output = mtd['MUSR00015193; Pair; pairTest; Asym; #1_Raw']


print(output.readY(0).mean())

Output:

-0.0141980129084

Categories: AlgorithmIndex | Muon\DataHandling

Source

C++ source: ApplyMuonDetectorGroupPairing.cpp (last modified: 2019-07-17)

C++ header: ApplyMuonDetectorGroupPairing.h (last modified: 2019-10-28)