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Indirect Inelastic Changes

Algorithms

New

Improved

  • The following changes were made to the MSDFit v1 algorithm:
    • Added model selection to the MSDFit v1 algorithm, with three current models: MsdGauss, MsdYi, and MsdYi. New models now work with workspaces in \(Q\) not \(Q^2\) (e.g. _eq workspaces ‘Elastic Q’).

  • The following changes were made to the the ConvolutionFitSequential v1 algorithm:
  • The following changes were made to the the ISISIndirectDiffractionReduction v1 algorithm:
    • Manual D-Ranges can now be supplied as a list/range, to the ISISIndirectDiffractionReduction v1 algorithm, each corresponding to their respective runs, in the supplied order.

    • The Sum Files option in the ISISIndirectDiffractionReduction v1 algorithm now allows for correctly corresponding each sum of sample runs defined with a range (e.g. A-B, where A and B are run numbers) to the corresponding vanadium run, dependent on D-Range.

    • The ‘Sample Runs’ field in the ISISIndirectDiffractionReduction v1 algorithm now recognizes 3 operators: ‘-’, ‘+’, ‘:’. The ‘-’ operator is used to supply a given range of runs and sum them when SumFiles is checked. The ‘+’ operator is used to supply a given list of runs and sum when SumFiles is checked. The ‘:’ operator is used to supply a range of runs, which will never be summed.

    • The Grouping Policy in ISISIndirectDiffractionReduction v1, now allows for grouping with a Workspace.

  • FlatPlatePaalmanPingsCorrection now supports Direct and Indirect modes.

  • BASISReduction can save to NXSPE format.

Bugfixes

  • ElasticWindowMultiple v1 now correctly normalizes by the lowest temperature - rather than the first one.

  • An issue has been fixed in IndirectILLEnergyTransfer v1 when handling the data with mirror sense, that have shifted 0 monitor counts in the left and right wings. This was causing the left and right workspaces to have different x-axis binning and to fail to sum during the unmirroring step.

  • An issue has been fixed in IndirectILLReductionFWS v1 when the scaling of the data after vanadium calibration was not applied.

  • CalculateSampleTransmission v1 now divides by the tabulated wavelength when calculating the absorption cross section.

Indirect Interfaces

  • The Indirect Absorption Corrections interface has been replaced with Calculate Monte Carlo Absorption Corrections; using the new CalculateMonteCarloAbsorption v1 algorithm.

  • In the Indirect ConvFit interface, EISF is now extracted as a parameter when performing a single fit using ‘Fit Single Spectrum’.

  • The Indirect S(Q, W) interface now automatically replaces NaN values with 0.

  • The Save Result option in the Indirect Elwin interface now writes to file the temperature-dependent elastic intensity normalized to the lowest temperature.

  • Model selection is available in the Indirect MSDFit interface, providing the option to choose one of the three models available in the MSDFit v1 algorithm.

  • Removed fit option from plot options drop-down menu, in the Indirect Bayes interface.

  • Use Manual Grouping in the Indirect Diffraction interface now functions in the same way as the equivalent option in the Indirect ISISEnergyTransfer interface; providing and option to choose the number of groups and subsequently grouping by detector.

  • Plot Current Preview is now an available option across all Indirect interfaces, where a mini-plot is shown within the interface.

Vesuvio

  • Added flag for disabling multiple scattering corrections: flags[‘ms_flags’][‘ms_enabled’].

  • Added method for specifying a mass by chemical symbol e.g. H for hydrogen, O for oxygen.

  • Multiple scattering corrections for back-scattering spectra now approximate the hydrogen peak, this is done in the VesuvioCorrections v1 algorithm. This feature is incomplete for 3.11.

  • VesuvioCorrections v1 has the additional property: ‘MassIndexToSymbolMap’. MassIndexToSymbolMap is used to map from an index of mass in the ‘Masses’ property to a chemical symbol.

  • VesuvioCorrections v1 takes the additional property: ‘HydrogenConstraints’. HydrogenConstraints are used to constrain the hydrogen peak for multiple scattering corrections in back-scattering spectra.

  • Gamma Corrections are no longer done for back-scattering spectra in the VesuvioCorrections v1 algorithm.

General

Dropped

Bugfixes

  • A number of Python indirect algorithms that use mantid.kernel.MaterialBuilder allowed setting the mass density for a material. The density was set incorrectly where the chemical formula had more than one atom, this is now fixed.

Full list of changes on GitHub