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Dear colleagues,<br>
<br>
In the past, I have often used the "PreMonitor_nD / Monitor_nD" pair
to investigate the origin of neutrons which reach the sample in a
upstream positon. For example:<br>
<br>
*******<br>
<br>
COMPONENT PreMon_CS_area_mon = PreMonitor_nD(monitor_comp =
CS_area_mon)<br>
AT (0,0,0.0001) RELATIVE ColdSource<br>
ROTATED (0,0,0) RELATIVE ColdSource<br>
<br>
COMPONENT CS_area_mon = Monitor_nD(xmin=-0.01, xmax=0.01,
ymin=-0.01, ymax=0.01,<br>
filename="CS_area_pre.psd",<br>
options= "x,y, all bins=50, all
limits=[-0.12 0.12], use premonitor")<br>
AT (0,0,0.0008) RELATIVE Arm_SAM_pos<br>
ROTATED (0,0,0) RELATIVE Arm_SAM_pos<br>
<br>
*******<br>
<br>
In the current versions of McStas, I am supposed to use the
"uservars" concept to investigate or plot the status of neutrons
earlier in the instrument. Unfortunately, after reading the manuals,
it is not entirely clear to me how I can use the "uservars" concept
to reconstruct the "PreMonitor_nD / Monitor_nD" bundle.<br>
<br>
I would be grateful for any help.<br>
<br>
Best wishes from the MLZ,<br>
<br>
Andreas Ostermann<br>
<br>
<br>
<div class="moz-signature">-- <br>
<b>Dr. Andreas Ostermann</b><br>
Instrument BIODIFF<br>
Technical University of Munich<br>
Forschungs-Neutronenquelle <br>
Heinz Maier-Leibnitz (FRM II) <br>
Lichtenbergstr. 1 <br>
85748 Garching <br>
Germany<br>
Tel.: +49 (0)89 289-14702<br>
<br>
<br>
<a href="mailto:andreas.ostermann@frm2.tum.de"
class="moz-txt-link-freetext"> andreas.ostermann@frm2.tum.de</a><br>
<a href="https://mlz-garching.de/"> www.mlz-garching.de </a><br>
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