McStas - Monte Carlo simulation of neutron instruments
McStas is an ongoing project to create a general tool for simulating
scattering instruments. The project is a collaboration between DTU
Physics (formerly RISØ DTU and RISØ Natnl. Lab),
University of Copenhagen, Paul Scherrer Institute and Institut
The Risø efforts have historically
been funded through multiple EU
The software is freely available and can be downloaded
from this site.
McStas is based on a compiler that reads a high-level specification
language defining the instrument to be simulated and produces C code
performs the Monte Carlo Simulation. The system is very fast in use,
when setting up the instrument definition and when doing calculations.
Typical figures are 500000 neutron histories per second on a fast
McStas supports triple-axis, time-of-flight instruments, and
neutrons. It comes with a comprehensive manual and a library of
components that include most standard elements of neutron scattering
including steady-state and pulsed sources, monochromators/analysers,
collimators, vanadium and powder samples, velocity selectors and
and a variety of detectors.
McStas has been found to run on all existing computer systems
(Unix/Linux, Windows, MacOS). Please refer to the platform requirements and tests
This software required a substantial effort to be brought to you. If
you enjoy this software, please use the folowing references in your
Conditions of use
Authors and contacts
McStas - Project funding
- K. Lefmann and K. Nielsen, Neutron News 10, 20, (1999).
- P. Willendrup, E. Farhi and K. Lefmann, Physica B, 350 (2004) 735.
Last Modified: Friday, 06-Jan-2012 10:30:30 CET