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# Diffraction Changes¶

## Powder Diffraction¶

• Added new diagrams showing the algorithms used in ISIS Powder scripts. These can be found at: ISIS Powder Diffraction Scripts Workflow Diagrams

• LoadILLAscii, which could be used to load D2B ASCII data into an MD workspace, has been removed. LoadILLDiffraction should be used instead.

• LoadILLDiffraction now supports loading D2B data with detector scans. The D2B IDF has been updated, as previously it contained some errors in the positions of the tubes and size of the pixels.

• AlignAndFocusPowder now correctly supports overloading the grouping file in the presence of a masking workspace.

• New algorithm Bin2DPowderDiffraction to bin TOF powder diffraction event data in $$(d,\,d_{\perp})$$ space has been developed.

• PDCalibration has changed how it calculates constants from peak positions to use a simplex optimization rather than Gauss-Markov method.

• ResampleX has a bug fix in how it automatically determines the data range for a workspace with multiple spectra.

• The powder diffraction GUI has had numerous bugfixes and now has an option to override the detector grouping.

• New set of routines for HRPD (ISIS Powder Diffraction Scripts - HRPD Reference), designed to replace and improve on the old CRI scripts

## Single Crystal Diffraction¶

• New algorithm SingleCrystalDiffuseReduction which performs the most common reductions done on Corelli (and elsewhere) for single crystal diffuse scattering.

• New algorithm ConvertMultipleRunsToSingleCrystalMD which loads, converts to single crystal MDWorkspace and combines a series of runs.

• FindPeaksMD has been modified to only add peaks to runs that contributed to that peak. This is a lot faster when multiple runs are in the same MDworkspace.

• New algorithm MDNormSCDPreprocessIncoherent creates the Solid Angle and Flux workspace from Vanadium data for MDNormSCD

• FindSXPeaks now finds all peaks in each spectrum. It also allows for setting more fine-grained resolutions. It can now also accept workspaces both in units of TOF and d-spacing.

• SCDCalibratePanels now adjusts the sample offsets and has an option to optimize the initial time-of-flight for better calibration of single crystal data.

• SCDCalibratePanels has CalibrateSnapPanels option to calibrate 3X3 banks of SNAP instrument for single crystal data.

• LoadIsawDetCal has not correctly aligned the detectors for SNAP since release 3.9. This bug that only impacted SNAP has been fixed.

## Engineering Diffraction¶

• The ISIS engineering diffraction interface has temporarily been disabled due to an issue with file search freezing Mantid when opening the interface.

## Imaging¶

• The IMAT IDF has been improved to more accurately represent the instrument.

Full list of diffraction changes on GitHub.