A horizontal reflectometer. The instrument is built of a 2.5 m long mirror and an inclined elliptical guide. The grazing angle is defined by a set of
slits. The sample size is 4cm x 4cm (horizontal sample).
The role of the mirror is to provide an angle of incidence of up to 4 deg and at the same time avoid a direct line of sight to the source.
The reflectivity is the ratio between the direct beam reflected beam intensities. Therefore two simulations are needed to get the reflectivity curve:
Example: mcrun Reflectometer.instr -n1e10 directbeam=1,thetasample=0.4,Qmin=0,Qmax=0.15 -d directbeam
Example: mcrun Reflectometer.instr -n1e10 directbeam=0,thetasample=0.4,Qmin=0,Qmax=0.15 -d reflectedbeam
Parameters in boldface are required;
the others are optional.
Minimum wavelength emitted by the cold moderator
Maximum wavelength emitted by the cold moderator
The angular resolution
The grazing angle
The minimum value of the interesting Qrange
The maximum value of the interesting Qrange
The width of the guide in the case of straight guide walls