McStas logo McStas - A neutron ray-trace simulation package ILL; PSI; Niels Bohr Institute DTU Physics NEXMAP


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McStas - A neutron ray-trace simulation package

McStas is a general tool for simulating neutron scattering instruments and experiments. It is actively supported by DTU Physics, NBI KU, PSI and ILL

Simulated scattering from a hollow-cylinder vanadium sample.

The plot shows the intensity of scattered neutrons (red is highest intensity). The sample is at the center of the sphere with the neutron beam coming from the left. Clearly seen is the shadowing effect of the sample causing a lower intensity opposite the beam. Also seen is the effect of the non-symmetric geometry of the sample, causing lower intensity directly above and to the side of the sample.

Recent news

March 10th, 2014: Public beta McStas 2.1rc1 available

A public beta-release of the forthcoming McStas 2.1 is now available.

As this is a beta-release that will be replaced by the official McStas 2.1, it is available via a special download page:

The public beta includes an updated model for the ESS moderator (ESS_moderator.comp), including the "pancake" brilliance model and vertical assymetry of the cold moderator brilliance. (Special thanks to Troels Schoenfeldt and Esben Klinkby!) The final McStas 2.1 may still include further improvements of this new source component.

Please also consult the new platform-oriented installation pages:

If you are on Unix (Linux/Mac) and want to keep your McStas 1.x or 2.0 alongside McStas 2.1rc or the forthcoming 2.1, please use our migration scripts

March 10th, 2014: Preparing for McStas 2.1

We are busy preparing for the release of McStas 2.1 within a couple of days and are reorganizing parts of the website for that reason. The updated list of changes for McStas can be found on our trac

Please bear with us if you have difficulties finding information or if the found information feels inconsistent. :-)

Looking forward to releasing McStas 2.1 in a couple of days!

Previous news items: 2013 2012, 2011, 2010, 2009, 2008, 2007, 2006, 2005, 2004, 2003,2002, 2001, 2000, 1999, 1998.

Last Modified: Monday, 10-Mar-2014 17:32:01 CET
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