IndirectTransmission v1

../_images/IndirectTransmission-v1_dlg.png

IndirectTransmission dialog.

Summary

Calculates the scattering & transmission for Indirect Geometry spectrometers.

Properties

Name Direction Type Default Description
Instrument Input string IRIS Instrument. Allowed values: [‘IRIS’, ‘OSIRIS’, ‘TOSCA’, ‘BASIS’, ‘VISION’]
Analyser Input string graphite Analyser. Allowed values: [‘graphite’, ‘mica’, ‘fmica’, ‘silicon’]
Reflection Input string 2 Reflection. Allowed values: [‘002’, ‘004’, ‘006’, ‘111’]
ChemicalFormula Input string Mandatory Sample chemical formula
NumberDensity Input number 0.1 Number denisty (atoms/Angstrom^3). Default=0.1
Thickness Input number 0.1 Sample thickness (cm). Default=0.1
OutputWorkspace Output Workspace Mandatory The name of the output workspace.

Description

Calculates the scattering & transmission for Indirect Geometry spectrometers at the elastic peak, as the transmission variation over wavelength is not substantial.

The sample chemical formula is input for the SetSampleMaterial algorithm to calculate the cross-sections. The instrument analyser reflection is selected to obtain the wavelength of the elastic peak to calculate the absorption cross-section. The sample number density & thickness is input to then calculate the percentage scattering & transmission.

Usage

Example - Running IndirectTransmission.

table_ws = IndirectTransmission(Instrument='IRIS', ChemicalFormula="C")
param_names = table_ws.column(0)
param_values = table_ws.column(1)

for pair in zip(param_names, param_values):
  print "%s : %s" % pair

Output:

Wavelength : 6.65800233718
Absorption Xsection : 0.0129590747304
Coherent Xsection : 5.551
Incoherent Xsection : 0.001
Total scattering Xsection : 5.552
Number density : 0.1
Thickness : 0.1
Transmission (abs+scatt) : 0.945870519609
Total scattering : 0.0540068963808

Example - Running IndirectTransmission with a specified number density and thickness.

table_ws = IndirectTransmission(Instrument='OSIRIS', NumberDensity=0.5, Thickness=0.3, ChemicalFormula="C")
param_names = table_ws.column(0)
param_values = table_ws.column(1)

for pair in zip(param_names, param_values):
  print "%s : %s" % pair

Output:

Wavelength : 6.65800233718
Absorption Xsection : 0.0129590747304
Coherent Xsection : 5.551
Incoherent Xsection : 0.001
Total scattering Xsection : 5.552
Number density : 0.5
Thickness : 0.3
Transmission (abs+scatt) : 0.433985627752
Total scattering : 0.565169943961

Categories: Algorithms | Workflow\MIDAS