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DgsAbsoluteUnitsReduction v1

../_images/DgsAbsoluteUnitsReduction-v1_dlg.png

DgsAbsoluteUnitsReduction dialog.

Summary

Process the absolute units sample.

Properties

Name

Direction

Type

Default

Description

InputWorkspace

Input

MatrixWorkspace

Mandatory

The absolute units sample workspace.

InputMonitorWorkspace

Input

MatrixWorkspace

A monitor workspace associated with the absolute units sample workspace

DetectorVanadiumWorkspace

Input

MatrixWorkspace

An absolute units detector vanadium workspace.

DetectorVanadiumMonitorWorkspace

Input

MatrixWorkspace

A monitor workspace associated with the absolute units detector vanadium workspace.

MaskWorkspace

Input

MatrixWorkspace

A masking workspace to apply to the data.

GroupingWorkspace

Input

MatrixWorkspace

A grouping workspace for the absolute units data.

ReductionProperties

Input

string

__dgs_reduction_properties

OutputWorkspace

Output

MatrixWorkspace

Mandatory

The integrated absolute units workspace.

OutputMaskWorkspace

Output

MatrixWorkspace

Mandatory

The diagnostic mask from the absolute units workspace

Description

This algorithm is responsible for taking an absolute units sample and converting it to an integrated value (one value for entire workspace) for that sample. A corresponding detector vanadium can be used in conjunction with the data reduction. The diagram below shows the workflow. The AbsUnitsIncidentEnergy parameter needs to be passed via a property manager since the absolute units sample may have been measured at an energy different from the sample of interest. Parameters in italics are controlled by the instrument parameter file (IPF) unless provided to the algorithm via a property manager. The mappings are given below.

Parameter

IPF Mapping

VanadiumMass

vanadium-mass

AbsUnitsMinimumEnergy

monovan-integr-min

AbsUnitsMaximumEnergy

monovan-integr-max

The last two parameters are used to create a single bin for the Rebin algorithm. The dashed oval parameter, VanadiumRmm, is taken from the atomic information for the molecular mass of Vanadium. The open circle represents detector diagnostic parameters and they are detailed in the table below.

Parameter

IPF Mapping

DetectorDiagnostic Mapping

HighCounts

diag_huge

HighThreshold

LowCounts

diag_tiny

LowThreshold

AbsUnitsLowOutlier

monovan_lo_bound

LowOutlier

AbsUnitsHighOutlier

monovan_hi_bound

HighOutlier

AbsUnitsMedianTestLow

monovan_lo_frac

LowThresholdFraction

AbsUnitsMedianTestHigh

monovan_hi_frac

HighThresholdFraction

AbsUnitsErrorBarCriterion

diag_samp_sig

SignificanceTest

If a detector vanadium is used, the processed sample workspace is multiplied by a factor containing the sample mass (SampleMass), sample molecular mass (SampleRmm) and the cross-section (Scattering XSec) given by: \(\frac{(\sigma^{V}_{incoherent}+\sigma^{V}_{coherent})\times10^{3}}{4\pi}\) with the cross-section units of \(millibarns/steradian\).

Workflow

../_images/DgsAbsoluteUnitsReduction-v1_wkflw.svg

Usage

Warning

This algorithm is not really intended for use at the command line, but is used within DgsReduction.

Categories: AlgorithmIndex | Workflow\Inelastic\UsesPropertyManager

Source

C++ header: DgsAbsoluteUnitsReduction.h

C++ source: DgsAbsoluteUnitsReduction.cpp