[ Identification | Description | Input parameters | Links ]

# The `Guide_wavy` Component

Neutron guide with gaussian waviness.

## Identification

- Site:
- Author: Kim Lefmann
- Origin: Risoe
- Date:

## Description

    Models a rectangular guide tube centered on the Z axis. The entrance lies
    in the X-Y plane.
    For details on the geometry calculation see the description in the McStas
    reference manual.

    Example: m=2 Qc=0.0218 (nat. Ni) W=1/300 alpha=4.38 R0=0.995 (given by Daniel Clemens, PSI)

    %BUGS
    This component does not work with gravitation on. Use component Guide_gravity then.

## Input parameters

Parameters in boldface are required; the others are optional.

Name | Unit | Description | Default |
w1 | m | Width at the guide entry |  |
h1 | m | Height at the guide entry |  |
w2 | m | Width at the guide exit | 0 |
h2 | m | Height at the guide exit | 0 |
l | m | length of guide |  |
R0 | 1 | Low-angle reflectivity | 0.995 |
Qc | AA-1 | Critical scattering vector | 0.0218 |
alpha | AA | Slope of reflectivity | 0 |
m | 1 | m-value of material. Zero means completely absorbing. | 0 |
W | AA-1 | Width of supermirror cut-off for all mirrors | 0 |
alpha1 | AA | Slope of reflectivity left | 4.38 |
m1 | 1 | m-value of material, left | 2 |
W1 | AA-1 | Width of supermirror cut-off left | 0.003 |
alpha2 | AA | Slope of reflectivity right | 4.38 |
m2 | 1 | m-value of material, right. | 2 |
W2 | AA-1 | Width of supermirror cut-off right | 0.003 |
alpha3 | AA | Slope of reflectivity top | 4.38 |
m3 | 1 | m-value of material, top. | 2 |
W3 | AA-1 | Width of supermirror cut-off top | 0.003 |
alpha4 | AA | Slope of reflectivity bottom | 4.38 |
m4 | 1 | m-value of material, bottom. | 2 |
W4 | AA-1 | Width of supermirror cut-off bottom | 0.003 |
wavy_z | deg | Waviness in the z-(flight-)direction | 0 |
wavy_xy | deg | Waviness in the transverse direction | 0 |

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

## Links

- Source code for `Guide_wavy.comp`.

[ Identification | Description | Input parameters | Links ]