3.5

HFIRLoad v1

../_images/HFIRLoad-v1_dlg.png

HFIRLoad dialog.

Summary

Load HFIR SANS data.

Properties

Name Direction Type Default Description
Filename Input string Mandatory The name of the input file to load. Allowed extensions: [‘.xml’]
OutputWorkspace Output MatrixWorkspace Mandatory Then name of the output workspace
NoBeamCenter Input boolean False If true, the detector will not be moved according to the beam center
BeamCenterX Input number Optional Beam position in X pixel coordinates
BeamCenterY Input number Optional Beam position in Y pixel coordinates
SampleDetectorDistance Input number Optional Sample to detector distance to use (overrides meta data), in mm
SampleDetectorDistanceOffset Input number Optional Offset to the sample to detector distance (use only when using the distance found in the meta data), in mm
Wavelength Input number Optional Wavelength value to use when loading the data file (Angstrom).
WavelengthSpread Input number 0.1 Wavelength spread to use when loading the data file (default 0.0)
OutputMessage Output string    
ReductionProperties Input string __sans_reduction_properties  

Description

Workflow algorithm that loads HFIR SANS data using the LoadSpice2D algorithm and applies basic corrections to the workspace. Those include:

  • Moving the detector at its proper position in Z.
  • Moving the detector according to the beam center.
  • Reading in the following wavelength and wavelength spread from the file and storing them in the logs.
  • Compute the source-sample distance according to the number of guides and store it in the logs.
  • Compute the beam diameter according to the distances and apertures, and store it in the logs: D_{beam} = (A_{source}+A_{sample})\frac{SDD}{SSD} + A_{sample}

This algorithm is rarely called directly. It is called by HFIRSANSReduction, which will pass along the relevant beam center information through the ReductionProperties property.

Usage

Note

To run these usage examples please first download the usage data, and add these to your path. In MantidPlot this is done using Manage User Directories.

Example - Load a BioSANS data file:

workspace = HFIRLoad('BioSANS_empty_cell.xml')
r= mtd['workspace'].run()
print "SDD = %g" % r.getProperty('sample-detector-distance').value

Output:

SDD = 6000

Categories: Algorithms | Workflow | SANS | UsesPropertyManager

Source

C++ source: HFIRLoad.cpp

C++ header: HFIRLoad.h