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StepScan v1¶

../_images/ImageNotFound.png — Enable screenshots using DOCS_SCREENSHOTS in CMake¶

Summary ¶

Workflow algorithm for analysis of an alignment scan from an SNS Adara-enabled beam line

Properties ¶

Name	Direction	Type	Default	Description
InputWorkspace	Input	EventWorkspace	Mandatory	The input workspace. Must hold ‘raw’ (unweighted) events.
OutputWorkspace	Output	TableWorkspace	Mandatory	The output table workspace.
MaskWorkspace	Input	MatrixWorkspace		A workspace holding pixels to be masked.
XMin	Input	number	Optional	The minimum value of X for which an event will be counted.
XMax	Input	number	Optional	The maximum value of X for which an event will be counted. Must be greater than XMin.
RangeUnit	Input	string	TOF	The units in which XMin and XMax is being given. Allowed values: [‘AtomicDistance’, ‘Degrees’, ‘DeltaE’, ‘DeltaE_inFrequency’, ‘DeltaE_inWavenumber’, ‘dSpacing’, ‘dSpacingPerpendicular’, ‘Empty’, ‘Energy’, ‘Energy_inWavenumber’, ‘Label’, ‘Momentum’, ‘MomentumTransfer’, ‘Phi’, ‘QSquared’, ‘SpinEchoLength’, ‘SpinEchoTime’, ‘Temperature’, ‘Time’, ‘TOF’, ‘Wavelength’]

This algorithm is for producing rocking curves from alignment scan runs. It is for use only with ADARA-style SNS datasets as it requires the ‘scan_index’ log variable. The algorithm optionally uses the MaskDetectors v1 and/or FilterByXValue v1 algorithms to restrict the region of data included. N.B. If these options are used, then this algorithm will modify the input workspace.

The SumEventsByLogValue v1 algorithm is then called, with ‘scan_index’ as the log to sum against. The row of the resulting table pertaining to scan_index=0 (which indicates ‘not a scan point’) is then removed.

Before then it will call other algorithms as shown in the flowchart, if the relevant inputs have been set. MaskDetectors v1 will be called if a MaskWorkspace is supplied. If either Xmin or Xmax or both are supplied, then FilterByXValue v1 algorithm is run to restrict the region of data included and if RangeUnit is not TOF, ConvertUnits v1 is run beforehand.

If necessary, the input workspace is cloned, to save it from being modified.