Component Manual for the Neutron Ray-Tracing Package McStas, version 3.8.6

4.1  The Arm McStas Component

Arm/optical bench

Identification

Description

An arm does not actually do anything, it is just there to set up a new coordinate system.

Example: Arm()

Input parameters

Parameters in boldface are required; the others are optional.

Name

Unit

Description

Default

Links

The generic component



Name:

Arm



Author:

System



Input parameters

(none)



Optional parameters

(none)



Notes




The component Arm is empty; is resembles an optical bench and has no effect on the neutron ray. The purpose of this component is only to provide a standard means of defining a local coordinate system within the instrument definition. Other components may then be positioned relative to the Arm component using the McStas meta-language. The use of Arm components in the instrument definitions is not required but is recommended for clarity. Arm has no input parameters.

The first Arm instance in an instrument definition may be changed into a Progress_bar component in order to display on the fly the simulation progress, and possibly save intermediate results.