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CombineDiffCal v1

../_images/CombineDiffCal-v1_dlg.png

CombineDiffCal dialog.

Table of Contents

Summary

Combine a per-pixel calibration with a grouped spectrum calibration

Properties

Name Direction Type Default Description
PixelCalibration Input TableWorkspace Mandatory OffsetsWorkspace generated from cross-correlation. This is the source of DIFCpixel.
GroupedCalibration Input TableWorkspace Mandatory DiffCal table generated from calibrating grouped spectra. This is the source of DIFCgroup.
CalibrationWorkspace Input MatrixWorkspace Mandatory Workspace where conversion from d-spacing to time-of-flight for each spectrum is determined from. This is the source of DIFCarb.
OutputWorkspace Output TableWorkspace   DiffCal table generated from calibrating grouped spectra
MaskWorkspace Input MaskWorkspace   MaskedWorkspace for PixelCalibration

Description

This algorithm combines pixel calibration results (\(prev\) subscript below) from the PixelCalibration workspace with the calibration of focussed data from PDCalibration (\(pd\) subscript below). The \(arb\) subscript below denotes values found in the CalibrationWorkspace.

Note

The GroupedCalibration table is assumed to not have \(DIFA\) or \(TZERO\) set. It is also assumed to have calibration values for all detector pixels.

The effective calibration values are calculated using the following equations

\[DIFC_{eff} = \frac{DIFC_{pd}}{DIFC_{arb}} * DIFC_{prev}\]

where \(DIFC_{pd}\) is from PDCalibration, \(DIFC_{arb}\) is found in the parameter CalibrationWorkspace that was the input workspace to PDCalibration, and \(DIFC_{prev}\) is from the previous calibration. The value of \(TZERO\) is unchanged

\[TZERO_{eff} = TZERO_{prev}\]

The value of \(DIFA\) is updated by

\[DIFA_{eff} = \left( \frac{DIFC_{pd}}{DIFC_{arb}} \right)^2 * DIFA_{prev}\]

If pixels are masked in MaskWorkspace, missing from PixelCalibration, or missing from the list of contributing pixels in CalibrationWorkspace, then the calibration constants found in GroupedCalibration will be copied.

Categories: AlgorithmIndex | Diffraction\Utility

Source

C++ header: CombineDiffCal.h

C++ source: CombineDiffCal.cpp