Position-sensitive monitor.
Author: Kim Lefmann
Origin: Risoe
Date: Feb 3, 1998
An (n times m) pixel PSD monitor. This component may also be used as a beam detector.
Example: PSD_monitor(xmin=-0.1, xmax=0.1, ymin=-0.1, ymax=0.1, nx=90, ny=90, filename="Output.psd")
Parameters in boldface are required; the others are optional.
|
Name |
Unit |
Description |
Default |
|
|
|||
|
nx |
1 |
Number of pixel columns |
90 |
|
ny |
1 |
Number of pixel rows |
90 |
|
filename |
string |
Name of file in which to store the detector image |
0 |
|
xmin |
m |
Lower x bound of detector opening |
-0.05 |
|
xmax |
m |
Upper x bound of detector opening |
0.05 |
|
ymin |
m |
Lower y bound of detector opening |
-0.05 |
|
ymax |
m |
Upper y bound of detector opening |
0.05 |
|
xwidth |
m |
Width of detector. Overrides xmin, xmax |
0 |
|
yheight |
m |
Height of detector. Overrides ymin, ymax |
0 |
|
restore_neutron |
1 |
If set, the monitor does not influence the neutron state |
0 |
|
nowritefile |
1 |
If set, monitor will skip writing to disk |
0 |
|
|
|||
|
|
|||
|
|
|||
Component source code found in file PSD_monitor.comp.
The component PSD_monitor resembles other monitors, e.g. TOF_Monitor, and also propagates the neutron ray to the detector surface in the \((x,y)\)-plane, where the detector window is set by the \(x\) and \(y\) input coordinates. The PSD monitor, though, is not sensitive to the arrival time of the neutron ray, but rather to its position. The rectangular monitor window, given by the \(x\) and \(y\) limits is divided into \(n_x \times n_y\) pixels.
The output from PSD_monitor is the integrated counts, \(n, I, M_2\), as well as three two-dimensional arrays of counts: \(n(x,y), I(x,y), M_2(x,y)\). The arrays are written to a file, filename, and can be read e.g. by the tool mcplot, see the system manual.