help

[Kristian Nielsen]

> I've just read your paper " McStas, a general software package for
> neutron ray-tracing simulations" published on Neutron News
> 10(1999),20-23. I'm very interested in Monte Carlo simulations of
> neutron scattering spectrometer. We are designing several
> spectrometers on China Advanced Research Reactor(CARR) under
> construction. These spectrometers include a high resolution powder
> diffractometer, a neutron reflectometer, a high Q diffractometer, a
> cold and a thermal neutron guide,and a three axis spectrometer.I hope
> I could use ray-tracing simulations technique and your software McStas
> in our design. My colleagues and I may need your help. First, what is
> ray-tracing simulations? Could you tell me some references which
> introduces this technique in details? Secondly, can this technique be

Well, maybe the best place to start would be to look at the McStas
manual. This may be downloaded from the McStas web page

    http://neutron.risoe.dk/mcstas/

If you have problems obtaining it, I can send you a paper copy.

> used in design of all of our spectrometers mentioned above?

Yes, McStas should be able to handle all of the instruments you
mentioned.

> Thirdly,besides in design, does this technique has any other usages in
> the running of our spectrometer after built up it in the future?  I

Yes. It can be used to select between different configuration before
starting an experiment, for example to get the best possible
signal/background ratio. And it can be used to compute eg. the
resolution function of an instrument which can be used to analyse
experiment data.

> hope you could give some help to me. I'm looking forward to hearing
> from you.

Do you know Sun Kai and Dong Feng Chen? If you do, you may be interested
to know that they have also started to look at Monte Carlo and McStas.

I hope this helps.

 - Kristian.