Geometry Definitions

Created by: padsley

This is more of a comment/request than a bug.

How is the geometry defined for detectors? There's the option to set R, theta, phi etc. and a 'Beta' which is probably the orientation of the system. How is this defined?

It would be good to have this in the guide somewhere.

P.S. I may have just missed this information but I'm in the middle of a nightshift and I have no idea what's happening anymore.