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ConvertHFIRSCDtoMDE v1¶

Summary ¶

Convert from the detector vs scan index MDHistoWorkspace into a MDEventWorkspace with units in Q_sample.

Properties ¶

Name	Direction	Type	Default	Description
InputWorkspace	Input	IMDHistoWorkspace	Mandatory	An input workspace.
Wavelength	Input	number	Mandatory	Wavelength
LorentzCorrection	Input	boolean	False	Correct the weights of events or signals and errors transformed into reciprocal space by multiplying them by the Lorentz multiplier: \(sin(2\theta)cos(\phi)/\lambda^3\)
MinValues	Input	dbl list	-10,-10,-10	It has to be 3 comma separated values, one for each dimension in q_sample.Values smaller then specified here will not be added to workspace.
MaxValues	Input	dbl list	10,10,10	A list of the same size and the same units as MinValues list. Values higher or equal to the specified by this list will be ignored
SplitInto	Input	int list	5	A comma separated list of into how many sub-grid elements each dimension should split; or just one to split into the same number for all dimensions. Default 5.
SplitThreshold	Input	number	1000	How many events in a box before it should be split. Default 1000.
MaxRecursionDepth	Input	number	20	How many levels of box splitting recursion are allowed. The smallest box will have each side length \(l = (extents) / (SplitInto^{MaxRecursionDepth}).\) Default 20.
ObliquityParallaxCoefficient	Input	number	1	Geometrical correction for shift in vertical beam position due to wide beam.
OutputWorkspace	Output	MDEventWorkspace	Mandatory	An output workspace.

This algorithm will convert the output of LoadWANDSCD v1 or the autoreduced data from DEMAND (HB3A) into a MDEventWorkspace in Q-sample, where every pixel at every scan point is converted to a MDEvent. This is similar to ConvertWANDSCDtoQ v1 except that it doesn’t histogram the data or do normalization. FindPeaksMD v1 can be run on the output Q sample space, then the UB can be found and used to then convert to HKL using ConvertWANDSCDtoQ v1 . IntegratePeaksMD v2 will also work on the output of this algorithm.

There is an option to apply the LorentzCorrection using the formula \(|\sin(2\theta)\cos(\phi)|/\lambda^3\). This helps lower the sloping background at low \(Q\).

Usage ¶

Example - ConvertHFIRSCDtoMDE

LoadWANDSCD(IPTS=7776, RunNumbers='26640-27944', OutputWorkspace='data',Grouping='4x4')
ConvertHFIRSCDtoMDE(InputWorkspace='data',
                    Wavelength=1.488,
                    OutputWorkspace='Q')