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Hi Bob,<br>
<br>
the Phi_c components are 'capture' ones, that is the flux is
weighted by the wavelength/1.8.<br>
Then you can have components which locally have a larger flux than
others.<br>
<br>
The last monitor 'lambda' has indeed a larger flux than the 'dxdy'.
The 'dxdy' has automatic limits for 'dx' and 'dy'. These limits may
be slightly shorter in range than the actual full beam divergence,
which would then get a smaller 'dxdy' flux than the total beam one.
<br>
The 'per cm2' option is OK if you use a Mcstas version 2.0. With
1.12c, do <b>not</b> use it, but divide manually the final flux by
its area (see Nov 28th 2011 bug report in
<a class="moz-txt-link-rfc2396E" href="http://mcstas.org/news/2011.html"><http://mcstas.org/news/2011.html></a>).<br>
<br>
Your options 'limits=[Lmin Lmax]' in the 'L' version will not work
as the 'options' string can only get keywords and numbers, not
variable symbols from the instrument parameters.<br>
You'd better use the 'min' and 'max' component parameters which are
then proper C code interpreted as an expression giving in the end a
value:<br>
<blockquote>COMPONENT Mon_10_L = Monitor_nD(
<br>
xwidth=0.01, yheight=0.01,
<b>min=Lmin, max=Lmax</b>,<br>
options="lambda, bins=20, parallel, per cm2, slit")<br>
</blockquote>
Hope you can get forward fast.<br>
Emmanuel.<br>
<br>
<br>
<br>
<div class="moz-cite-prefix">On 02/05/2013 09:21 AM, cubitt wrote:<br>
</div>
<blockquote cite="mid:5110C0EF.8070701@ill.fr" type="cite">Dear
Emanuel,
<br>
<br>
Im trying to knock up a simple simulation of D11 and have got into
trouble trying to
<br>
work out what the actual flux is using monitor components you had
in your H15
<br>
simulation.
<br>
<br>
The trouble I have is in the print out, shown at the bottom, the
"I" value is not the same for
<br>
those monitors and not only that that number appears to be
proportional to "N" the
<br>
number of events in the simulation. It always rises when I click
update.
<br>
<br>
The sum of the intensities in the files created also gives
completely different numbers.
<br>
<br>
My question is how do I measure the flux over a 1 cm^2 detector at
the sample position?
<br>
<br>
Sorry for the dumb question. Its been a few years since I used
Mcstas
<br>
<br>
Regards,
<br>
<br>
Bob
<br>
<br>
<br>
<br>
<br>
<br>
COMPONENT Mon_10_dxdy = Monitor_nD(
<br>
xwidth=0.01, yheight=0.01,
<br>
options="dx dy, all auto, parallel, per cm2, slit")
<br>
AT (0,0,0) RELATIVE PREVIOUS
<br>
<br>
COMPONENT Mon_10_Phic = Monitor_nD(
<br>
xwidth=0.01, yheight=0.01,
<br>
options="x y dx dy, all auto, parallel, per cm2, capture, slit")
<br>
AT (0,0,0) RELATIVE PREVIOUS
<br>
<br>
COMPONENT Mon_10_L = Monitor_nD(
<br>
xwidth=0.01, yheight=0.01,
<br>
options="lambda, limits=[Lmin Lmax] bins=20, parallel, per cm2,
slit")
<br>
AT (0,0,0) RELATIVE PREVIOUS
<br>
<br>
<br>
Detector: Mon_10_dxdy_I=4.95391e+06 Mon_10_dxdy_ERR=1447.26
Mon_10_dxdy_N=306 "Mon_10_dxdy_1360049312.HD_VD"
<br>
Detector: Mon_10_Phic_I=1.37179e+07 Mon_10_Phic_ERR=3547.17
Mon_10_Phic_N=255 "Mon_10_Phic_1360049312.x"
<br>
Detector: Mon_10_Phic_I=1.37188e+07 Mon_10_Phic_ERR=3535.36
Mon_10_Phic_N=255 "Mon_10_Phic_1360049312.y"
<br>
Detector: Mon_10_Phic_I=1.37192e+07 Mon_10_Phic_ERR=3530.86
Mon_10_Phic_N=255 "Mon_10_Phic_1360049312.HD"
<br>
Detector: Mon_10_Phic_I=1.37179e+07 Mon_10_Phic_ERR=3547.17
Mon_10_Phic_N=255 "Mon_10_Phic_1360049312.VD"
<br>
Detector: Mon_10_L_I=5.65996e+06 Mon_10_L_ERR=1123.31
Mon_10_L_N=427 "Mon_10_L_1360049312.L"
<br>
<br>
</blockquote>
<br>
<pre class="moz-signature" cols="72">--
Emmanuel FARHI,<a class="moz-txt-link-abbreviated" href="http://www.ill.eu/computing/people/emmanuel-farhi">www.ill.eu/computing/people/emmanuel-farhi</a> \|/ ____ \|/
CS-Group ILL4/221, Institut Laue-Langevin (ILL) Grenoble ~@-/ oO \-@~
6 rue J. Horowitz, BP 156, 38042 Grenoble Cedex 9,France /_( \__/ )_\
Work :Tel (33/0) 4 76 20 71 35. Fax (33/0) 4 76 48 39 06 \__U_/
</pre>
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