The `First_Chopper` component

Author: Philipp Bernhardt
Origin: McStas release
Date: Januar 22 1999
Version: 1.3

First disk chopper after a continuous neutron source.

Identification

Models a disc chopper at the first place.  

Example values: w=0.05 R=0.5 f=2500 n=3 pha=0 a=2

Parameters in boldface are required; the others are optional.

Name	Unit	Description
w	m	Width of the slits
R	m	Radius of the Chopper
f	rad/s	angular frequency of the Chopper
n	1	Number of slits
pha	s	Phase
a	1	Number of pulses

Name	Unit	Description	Default
Tg
To