Diffraction Changes

Powder Diffraction

New features

  • (#40659) The PDFFourierTransform v2 algorithm has a new minimum range limit, Rmin for Direction="Forward" and Qmin for Direction="Backward".

  • (#40042) HFIR MIDAS instrument definition has been added.

  • (#40035) AlignAndFocusPowderSlim now outputs multiple workspaces, one for each target, when using the SplitterWorkspace property. The SplitterTarget property has been removed.

  • (#40095) The PawleyPattern1D class now supports Pawley refinement of TOF workspaces and has new TOF peak profile class BackToBackGauss for a back-to-back exponential convoluted with a Gaussian.

  • (#40095) The PawleyPattern1D class now supports zero shift and scale factor for reflection d-spacings (equivalent to modifying TZERO and DIFC).

  • (#40478) StitchByBackground v1 has been added, which allows for multiple workspaces with different bin widths to be stitched together.

  • (#40571) AlignAndFocusPowderSlim can now accept a mantid.dataobjects.GroupingWorkspace (via the GroupingWorkspace property) to define which detectors go to which output spectra.

  • (#40643) AlignAndFocusPowderSlim is no longer hard-coded for the VULCAN instrument.

Bugfixes

Engineering Diffraction

New features

  • (#40668) The Engineering Diffraction interface can now perform Vanadium normalisation during calibration.

  • (#39922) The Engineering Diffraction interface has two new tabs, Absorption Correction and Texture.

    • The new Absorption Correction tab corrects workspaces for the beam attenuation through the sample.

    • The new Texture tab combines data from focused workspaces and peak fitting and plots pole figures for experimental data.

    • Basic usage of these tabs as part of a texture analysis reduction pipeline has been documented in the texture technique documentation.

  • (#39931) The automated peak fitting routine Engineering.texture.TextureUtils.fit_all_peaks has been updated to improve robustness, particularly in terms of fitting peak positions.

  • (#40326) CreatePoleFigureTableWorkspace v1 has two new input properties. SpectraWorkspace is the name for a new output workspace which contains spectra corresponding to rows in the standard OutputWorkspace table. IncludeSpectrumInfo is a flag which adds information columns to the final OutputWorkspace about where each spectra has come from.

  • (#40326) The Engineering.texture.texture_helper module has been created to hold stand alone texture functionality which is independent of specific instrument workflows or workflow classes:

    • show_texture_sample_shape shows the sample present on a workspace along with the texture sample directions, and optionally a gauge volume.

    • load_all_orientations takes a sequence of workspaces and apply sample orientations, loaded from an input file (as described in the orientation file section of the Texture Analysis Concept doc).

    • create_pole_figure_tables creates a single pole figure table for a sequence of workspaces and their fit parameters.

    • plot_pole_figure creates a pole figure plot for a pole figure table.

    • Pole figure plots created by create_pole_figure_tables and plot_pole_figure have flags to add interactive annotation of points in the pole figure (include_spec_info and display_debug_info respectively). You can also access this information bt holding the “a” key on the keyboard clicking.

  • (#40891) The peak fitting routine Engineering.texture.TextureUtils.fit_all_peaks now outputs a column for each parameter giving the ratio of value to error.

  • (#40441) EnggEstimateFocussedBackground v1 now uses multi-threading to speed up execution time by factor ~2-3.

  • (#40599) Added calibrated IDF for POLDI (PSI) post upgrade in December 2025.

  • (#40599) New loader load_poldi_h5f for h5f file produced by POLDI post instrument upgrade available in plugins.algorithms.poldi_utils.

  • (#40599) New features in PoldiAutoCorrelation v6:

    • Added parameter NGroups to split POLDI detectors into groups and produce an autocorrelation spectrum per grouping.

    ../../_images/poldi-ngroups.png

    • Detector IDs are now associated with autocorrelation spectra in the output workspace.

  • (#40599) New features in the PawleyPattern1D class from Engineering.pawley_utils:

    • fit_no_constraints method to perform ‘free’ fit - i.e. do not constrain peak centres to predicted positions.

    • Improvements to the robustness of background estimation.

    • fit_background method to fit background function to 1D data using a cost function that is biased to be less sensitive to positive outliers.

  • (#40599) Added PawleyPattern2DNoConstraints class in Engineering.pawley_utils to do a ‘free’ 2D refinement of POLDI data

Bugfixes

Single Crystal Diffraction

New features

  • (#40042) Added HFIR IMAGINE instrument image plate instrument definition.

  • (#40187) Added new instrument IMAGINE-X.

Bugfixes

Release 6.15.0