[ Identification | Description | Input parameters | Links ]

# The `Mirror` Component

Single mirror plate.

## Identification

- Site:
- Author: Kristian Nielsen
- Origin: Risoe
- Date: August 1998

## Description

    Single mirror plate (used to build guides in compound components).
    The component Mirror models a single rectangular neutron mirror plate.
    It can be used as a sample component or to e.g. assemble a complete neutron
    guide by putting multiple mirror components at appropriate locations and
    orientations in the instrument definition, much like a real guide is build
    from individual mirrors.
    Additionally, it may be centered in order to be used as a sample or
    monochromator plate, else it starts from AT position.
    Reflectivity is either defined by an analytical model (see Component Manual)
    or from a two-columns file with q [Angs-1] as first and R [0-1] as second.
    In the local coordinate system, the mirror lies in the first quadrant of the
    x-y plane, with one corner at (0, 0, 0). Plane is thus perpendicular to the
    incoming beam, and should usually be rotated.

    Example: Mirror(xwidth=.1, yheight=.1,R0=0.99,Qc=0.021,alpha=6.1,m=2,W=0.003)

## Input parameters

Parameters in boldface are required; the others are optional.

Name | Unit | Description | Default |
reflect | str | Name of reflectivity file. Format q(Angs-1) R(0-1) | 0 |
xwidth | m | width of mirror plate |  |
yheight | m | height of mirror plate |  |
R0 | 1 | Low-angle reflectivity | 0.99 |
Qc | AA-1 | Critical scattering vector | 0.021 |
alpha | AA | Slope of reflectivity | 6.07 |
m | 1 | m-value of material. Zero means completely absorbing. | 2 |
W | AA-1 | Width of supermirror cut-off | 0.003 |
center | 1 | if true (1), the Mirror is centered arount AT position. | 0 |
transmit | 1 | When true, non reflected neutrons are transmitted through the mirror, instead of being absorbed. | 0 |

AT ( | , | , |  | ) RELATIVE |  |
ROTATED ( | , | , |  | ) RELATIVE |

## Links

- Source code for `Mirror.comp`.

[ Identification | Description | Input parameters | Links ]