Instrumentation, simulation and virtual experiments – University of Copenhagen

X-Ray and Neutron Science > Research > Instrumentation, simul...

Instrumentation, simulation and virtual experiments

In collaboration with DTU Physics, the group is developing the leading software packages for simulation of neutron and X-ray scattering instruments: McStas ( and McXtrace (

These codes are able to perform realistic simulations of full experimental set-ups, including scattering from the sample and unvanted scattering from sample environment.

McStas is strongly used in the design of instruments for the European Spallation Source, ESS, and presently the group is leading these simulation efforts. The ESS simulations are primarily based on more than

10 students, who through different projects provide very valuable input to the design of the facility. It is foreseen that McXtrace will play a similar role in the design of instruments for the X-ray facility MAX-IV.

The simulation activities comprise:

  • Basic development, test, and documentation of the packages
  • Simulation of individual optical components, e.g. imperfect mirrors, lenses, and neutron guides
  • Simulation of neutron guide systems for maximal neutron transfer
  • Simulation and design of full beamlines for maximal performance; for ESS and other European facilities, e.g. PSI and FRM-2.
  • Development of models for scattering from samples
  • Simulation of full instrument set-ups, including samples. So-called Virtual Experiments.
  • Use of Virtual Experiments for determining experimental parameters e.g. signal, background, resolution, and multiple scattering
  • Use of Virtual Experiments for testing data analysis algorithms
  • Use of Virtual Experiments for classroom or online teaching purposes ("flight simulator")

For further information, contact Associate Prof. Kim Lefmann