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IndirectILLReductionFWS v1

../_images/IndirectILLReductionFWS-v1_dlg.png

IndirectILLReductionFWS dialog.

Summary

Performs fixed-window scan (FWS) multiple file reduction (both elastic and inelastic) for ILL indirect geometry data, instrument IN16B.

Properties

Name Direction Type Default Description
Run Input list of str lists Mandatory Run number(s) of sample run(s). Allowed values: [‘nxs’]
BackgroundRun Input list of str lists   Run number(s) of background (empty can) run(s). Allowed values: [‘nxs’]
CalibrationRun Input list of str lists   Run number(s) of vanadium calibration run(s). Allowed values: [‘nxs’]
CalibrationBackgroundRun Input list of str lists   Run number(s) of background (empty can) run(s) for vanadium run. Allowed values: [‘nxs’]
Observable Input string sample.temperature Scanning observable, a Sample Log entry
SortXAxis Input boolean False Whether or not to sort the x-axis
BackgroundScalingFactor Input number 1 Scaling factor for background subtraction
CalibrationBackgroundScalingFactor Input number 1 Scaling factor for background subtraction for vanadium calibration
BackgroundOption Input string Sum Whether to sum or interpolate the background runs. Allowed values: [‘Sum’, ‘Interpolate’]
CalibrationOption Input string Sum Whether to sum or interpolate the calibration runs. Allowed values: [‘Sum’, ‘Interpolate’]
CalibrationBackgroundOption Input string Sum Whether to sum or interpolate the background run for calibration runs. Allowed values: [‘Sum’, ‘Interpolate’]
MapFile Input string   Filename of the detector grouping map file to use. By default all the pixels will be summed per each tube. Use .map or .xml file (see GroupDetectors documentation) only if different range is needed for each tube. Allowed values: [‘map’, ‘xml’]
ManualPSDIntegrationRange Input long list 1,128 Integration range of vertical pixels in each PSD tube. By default all the pixels will be summed per each tube. Use this option if the same range (other than default) is needed for all the tubes.
Analyser Input string silicon Analyser crystal. Allowed values: [‘silicon’]
Reflection Input string 111 Analyser reflection. Allowed values: [‘111’, ‘311’]
OutputWorkspace Output WorkspaceGroup Mandatory Output workspace group
SpectrumAxis Input string SpectrumNumber The spectrum axis conversion target. Allowed values: [‘SpectrumNumber’, ‘2Theta’, ‘Q’, ‘Q2’]
DiscardSingleDetectors Input boolean False Whether to discard the spectra of single detectors.
ManualInelasticPeakChannels Input long list -1,-1 The channel indices for the inelastic peak positions in the beginning and in the end of the spectra; by default the maxima of the monitor spectrum will be used for this. The intensities will be integrated symmetrically around each peak.
GroupDetectors Input boolean True Group the pixels using the range, tube-by-tube (default) or in a custom way; it is not recommended to group the detectors at this stage, in order to get absorption corrections right, however the default value is True for backwards compatibility.

Description

This algorithm performs Fixed Window Scan (FWS) data reduction (both Elastic and Inelastic) for IN16B indirect geometry instrument at ILL. It uses internally the IndirectILLEnergyTransfer algorithm.

Input

Multiple files following the syntax given in MultipleFileProperty.

Output

A WorkspaceGroup that contains as many workspaces as many distinct Doppler’s energy values were present in input files list (including E=0 for EFWS). Each Workspace in the group will have the given observable as the x-axis and as many bins, as many files were given corresponding to the same energy. Y-axis will be detector angle, and the values would be the intensities integrated over the whole spectra (for EFWS) or over the two peaks (symmetric around each peak) at the beginning and the end of the spectra (for IFWS). Scanning observable can be any numeric or time-stamp-like string parameter. See sample.* or e.g. start_time in Sample Logs. BackgroundRun s, CalibrationBackgroundRun s and CalibrationRun s will be averaged (default) or interpolated over all the observable points according to the option. Interpolation is provided by SplineInterpolation, which does cubic spline (or linear for 2 points only) interpolation inside the range and flat extrapolation beyond the range. For the moment it does not give errors on interpolated results. Interpolated subtraction or calibration is recommended only if there is a strong dependence on the observable and many measured points in the data to be interpolated.

Usage

Example: EFWS+IFWS

ws = IndirectILLReductionFWS(Run='ILL/IN16B/083072:083077.nxs')
print("Result is now a WorkspaceGroup, which has {:d} workspaces, one per each energy value".format( ws.getNumberOfEntries()))
print("first item, called {} corresponds to energy value of {}".format(
ws.getItem(0).name(),ws.getItem(0).name().split('_')[1]))
print("it has {:d} histograms and {:d} bins, one per each temperature".format(
ws.getItem(0).getNumberHistograms(),ws.getItem(0).blocksize()))

Output:

Result is now a WorkspaceGroup, which has 3 workspaces, one per each energy value
first item, called ws_0.0_red corresponds to energy value of 0.0
it has 18 histograms and 2 bins, one per each temperature

Categories: AlgorithmIndex | Workflow\MIDAS | Workflow\Inelastic | Inelastic\Indirect | Inelastic\Reduction | ILL\Indirect