McStas and McXtrace 3.7.1 released

Installation instructions

• For McStas go to The McStas install page on GitHub
• For McXtrace go to The McXtrace install page on GitHub

What’s Changed

Main new developments:

Common McStas and McXtrace developments:

• Up to 10 USERVARS supported with Monitor_nD (named user0,...,user9)
• Qt5 -> Qt6 across the package and dependencies
• Bugfix: Fix of rare visualisation bug in mcdisplay/mxdisplay (e.g. box was not allowed as a comp name)
• Doc improvements:
  • mcdoc/mxdoc can render .tex and .md in addition to .html
  • Example instruments come with an in-repo README.md generated via this mechanism
  • See e.g. McStas BNL_H8 or McXtrace ESRF ID01
• CI/test improvements:
  • mcdisplay/mxdisplay visualisation is performed as part of mctest/mxtest runs (-> CI)
  • See top html files in McStas and McXtrace nightly test runs

McStas specific developments:

• Integrated support for KDSource
  • New component KDSource
  • For usage details, see example instrument Test_KDSource and the KDSource documentation website
  • Available as automatic dependency on conda-forge based installations (including macOS and Windows ‘installers’
  • Not available as .deb package on Debian systems but may function by installing via pip. 
    Recommendation: Just use conda-forge.
• Pulse-length adjustment available for ESS_butterfly
  • Handled via specifically named instrument input parameter and DEPENDENCY line
  • See example instrument ESS_butterfly_Adjustable_Pulse
• PowderN now supports NCrystalcfg-strings.
  • Forwards request to NCrystal that populates datastructures without intermediate .laz/.lau files
  • See example instrument Test_Powders – comp=0 mode
• Bugfixes:
  • Fix to Union, orientation of loggers wrt. master comp
  • Bugfixes to recently added improved Union mesh
• Contributions from NBI/KU:
  • Inhomogenous_incoherent_process in Union from @Lomholy, (via ‘tinyexpr’ string-expression inputs) – see rel. test instrument
  • New spinwave comp SpinWave_BCO from @SSBNS – see rel. test instrument
  • ESS KVASIR instrument proposal – backend instrument with MCPL input from BIFROST optic. @AmalieFalkenberg. Includes Jupyter notebook in McStasScript syntax.
• McStas component manual uses .tex snippets from generated via components mcdoc

McXtrace specific developments:

• Much improved Union subsystem for McXtrace by @ebknudsen. Makes use of Xraylib for Compton and Rayleigh scattering models.
• Test instruments for the new Union processes, both from @ebknudsen
  • PowderCompton_union – Compton scattering and powder diffraction
  • Test_KN_Comp_Rayl_union – test instrument using Klein-Nishina, Rayleigh, or Compton
    scattering processes.

New Contributors

• @SSBNS made their first contribution in #2373
• @AmalieFalkenberg made their first contribution in #2345

Best regards on behalf of McStas/McXtrace,

Peter Kjær Willendrup
Forskningsingeniør, Specialkonsulent
DTU Physics