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McStas: MultiDiskChopper

[ Identification | Description | Input parameters | Links ]

The MultiDiskChopper Component

Based on DiskChopper (Revision 1.18) by Peter Willendrup (2006), which in turn is based on Chopper (Philipp Bernhardt), Jitter and beamstop from work by Kaspar Hewitt Klenoe (jan 2006), adjustments by Rob Bewey (march 2006)

Identification

  • Site:
  • Author: Markus Appel
  • Origin: ILL / FAU Erlangen-Nuernberg
  • Date: 2015-10-19

Description

Models a disk chopper with a freely configurable slit pattern. For simple applications,
use the DiskChopper component and see the component manual example of DiskChopper GROUPing.
If the chopper slit pattern should be dynamically configurable or a complicated pattern
is to be used as first chopper on a continuous source, use this component.

Width and position of the slits is defined as a list in string parameters so
they can easily be taken from instrument parameters.
The chopper axis is located on the y axis as defined by the parameter delta_y.
When the chopper is the first chopper after a continuous (i.e. time-independent)
source, the parameter isfirst should be set to 1 to increase Monte-Carlo efficiency.


Examples (see parameter definitions for details):
Two opposite slits with 10 and 20deg opening, with the 20deg slit in the beam at t=0.02:
MultiDiskChopper(radius=0.2, slit_center="0;180", slit_width="10;20", delta_y=-0.1,
nu=302, nslits=2, phase=180, delay=0.02)

First chopper on a continuous source, creating pulse trains for one additional revolution
before and after the revolution at t=0:
MultiDiskChopper(radius=0.2, slit_center="0;180", slit_width="10;20", delta_y=-0.1,
nu=302, nslits=2, phase=180, isfirst=1, nrev=1)

Input parameters

Parameters in boldface are required; the others are optional.
NameUnitDescriptionDefault
slit_center"0 180"
slit_width"10 20"
nslitsNumber of slits to read from slit_width and slit_center2
delta_ymy-position of the chopper rotation axis. If the chopper is located above-0.3
nu0
nrev0
ratio1
jitter0
delay0
isfirst0
phase0
radiusmOuter radius of the disk0.375
equal0
abs_out0
verbose0
AT ( , , ) RELATIVE
ROTATED ( , , ) RELATIVE

Links


[ Identification | Description | Input parameters | Links ]

Generated on 2024-01-03 11:47:43


Last Modified: Wednesday, 03-Jan-2024 19:59:11 CET
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