[neutron-mc] problem(?) with component monochromator_flat...
Emmanuel Farhi
farhi at ill.fr
Tue Jun 1 10:35:42 CEST 2004
Hi Ulrich,
You are right, you may use groups in order to catch the neutrons that do not follow the
'right' way, or an other solution is to use the Monitor_nD with "parallel" word in the
option string parameter (this does about the same job as GROUP but only for
monitors...).
Emmanuel.
"Ulrich C. Wildgruber MPI fuer Metallforschung Stuttgart" wrote:
> "Ulrich C. Wildgruber MPI fuer Metallforschung Stuttgart" wrote:
> >
> > Hi everybody!
> >
> > I'd like to draw your attention to an instrument file (attached) were
> > we don't understand what happens for certain input parameter sets:
> >
> > parameter set 1: TTM = 80.0
> > PHM = 40.0
> > E = 4.131meV (4.45A)
> > DWERT = 3.461(A)
> >
> > parameter set 2: TTM = 84.0
> > PHM = 42.0
> > E = 4.131meV
> > DWERT = 3.325
> >
> > If I did Bragg's equation right we should see a reflection in both
> > cases. However the intensity is 0 for parameter set "2".
> > What are we doing wrong?
> >
> > Any advice is appreciated!
> >
> > Thanks
> >
> > Ulrich
> >
> > --
> > Ulrich WILDGRUBER
> > wildgrub at dxray.mpi-stuttgart.mpg.de
> > wwwmf.mpi-stuttgart.mpg.de/abteilungen/dosch/dosch.html
> > -----------------------------------------------------------------------------
> > Max-Planck-Institut für Metallforschung | Technische Universität München
> > Heisenbergstr. 3 | ZWE Neue Forschungs-Neutronenquelle
> > | Instrumentierung
> > D-70569 Stuttgart | D-85747 Garching/München
> > Tel.: (+49)-711-689-1900 | Tel.: (+49)-89-289-14681
> > Fax.: (+49)-711-689-1902 | Fax.: (+49)-89-289-14666
> >
> > --------------------------------------------------------------------------------
> > DEFINE INSTRUMENT MCRY_test(TTM, PHM, E, DWERT)
> >
> > /* test version 05/2004 */
> > /* */
> >
> > DECLARE
> > %{
> > double dist1 = 2.5;
> > double dist2 = 2.5;
> > double beam_width = 0.05;
> > double beam_height = 0.05;
> > double mos0 = 22.6;
> > double ref0 = 0.7;
> > %}
> >
> > INITIALIZE
> > %{
> > %}
> >
> > TRACE
> >
> > COMPONENT a1 = Arm()
> > AT (0,0,0) ABSOLUTE
> >
> > /*
> > COMPONENT source = Source_div_lambda(
> > width = 0.062,
> > height = 0.122,
> > hdiv = 1.0,
> > vdiv = 1.0,
> > //lambda_0 = 2.0,
> > lambda_0 = LAMBDA,
> > d_lambda = 0.1)
> > AT (0,0,0) RELATIVE a1 ROTATED (0,0,0) RELATIVE a1
> > */
> >
> > COMPONENT source = Source_div(
> > width = 0.062,
> > height = 0.122,
> > hdiv = 1.0,
> > vdiv = 1.0,
> > E0 = E,
> > dE = 0.1)
> > AT (0,0,0) RELATIVE a1 ROTATED (0,0,0) RELATIVE a1
> >
> > /* monitoring primary beam... */
> > COMPONENT sum1 = Monitor(
> > xmin = -0.1, xmax = 0.1,
> > ymin = -0.1, ymax = 0.1)
> > AT(0, 0, dist1+0.0171) RELATIVE a1 ROTATED (0,0,0) RELATIVE a1
> >
> > COMPONENT psd1 = PSD_monitor(
> > xmin = -0.1, xmax = 0.1,
> > ymin = -0.1, ymax = 0.1,
> > nx = 41,
> > ny = 41,
> > filename = "NL1.psd")
> > AT(0, 0, dist1+0.0172) RELATIVE a1 ROTATED (0,0,0) RELATIVE a1
> >
> > COMPONENT div1 = Divergence_monitor(
> > xmin = -0.1, xmax = 0.1,
> > ymin = -0.1, ymax = 0.1,
> > nh = 41,
> > nv = 41,
> > h_maxdiv = 2.0,
> > v_maxdiv = 2.0,
> > filename = "NL1.div")
> > AT(0, 0, dist1+0.0173) RELATIVE a1 ROTATED (0,0,0) RELATIVE a1
> >
> > /* end of monitoring primary beam... */
> >
> > /********************************************************/
> > /* Monochromator */
> > /********************************************************/
> > /****************************************/
> > /* center crystal package - position 0 */
> > /****************************************/
> >
> > COMPONENT mono0 = Arm()
> > AT (0, 0, dist1+0.167+0) RELATIVE a1 ROTATED (0, PHM, 0) RELATIVE a1
> >
> > COMPONENT m0 = Monochromator_flat(
> > zmin = -0.011, zmax = +0.011,
> > ymin = -0.003, ymax = +0.003,
> > mosaich = mos0,
> > mosaicv = mos0,
> > r0 = ref0,
> > DM = DWERT)
> > AT (0, 0, 0) RELATIVE mono0 ROTATED (0, 0, 0) RELATIVE mono0
> >
> > /* monitoring transmitted beam... */
> > COMPONENT psd2 = PSD_monitor(
> > xmin = -beam_width, xmax = beam_width,
> > ymin = -beam_height, ymax = beam_height,
> > nx = 41,
> > ny = 41,
> > filename = "MatDet2.psd")
> > AT(0, 0, dist1+.501) RELATIVE a1 ROTATED (0,0,0) RELATIVE a1
> >
> > COMPONENT sum2 = Monitor(
> > xmin = -beam_width, xmax = beam_width,
> > ymin = -beam_height, ymax = beam_height)
> > AT(0, 0, dist1+0.502) RELATIVE a1 ROTATED (0,0,0) RELATIVE a1
> > /* end of monitoring transmitted beam... */
> >
> > /* Bragg reflected beam along a2 */
> > COMPONENT a2 = Arm()
> > AT (0, 0, 0) RELATIVE mono0 ROTATED (0, TTM, 0) RELATIVE a1
> >
> > /* monitoring Brag reflected beam... */
> > COMPONENT psd3 = PSD_monitor(
> > xmin = -beam_width, xmax = beam_width,
> > ymin = -beam_height, ymax = beam_height,
> > nx = 41,
> > ny = 41,
> > filename = "MatDet3.psd")
> > AT(0, 0, dist2+0.001) RELATIVE a2 ROTATED (0,0,0) RELATIVE a2
> >
> > COMPONENT sum3 = Monitor(
> > xmin = -beam_width, xmax = beam_width,
> > ymin = -beam_height, ymax = beam_height)
> > AT(0, 0, dist2+0.002) RELATIVE a2 ROTATED (0,0,0) RELATIVE a2
> >
> > COMPONENT div3 = Divergence_monitor(
> > xmin = -beam_width, xmax = beam_width,
> > ymin = -beam_height, ymax = beam_height,
> > nh = 41,
> > nv = 41,
> > h_maxdiv = 2.0,
> > v_maxdiv = 2.0,
> > filename = "MatDet3.div")
> > AT(0, 0, dist2+0.004) RELATIVE a2 ROTATED (0,0,0) RELATIVE a2
> > /* end of monitoring Bragg reflected beam... */
> >
> > END
> >
> > --------------------------------------------------------------------------------
> > _______________________________________________
> > neutron-mc mailing list
> > neutron-mc at risoe.dk
> > http://neutron.risoe.dk/mailman/listinfo/neutron-mc
>
> Hi again!
>
> Sorry for bothering everybody with my little problem on Friday.
> I was not aware of the fact that my components 'psd2' and 'sum2'
> which were supposed to monitor the beam transmitted through the
> monochromator caused the strange behaviour.
> Do I need to learn how to use 'groups' to avoid this effect?
> Thanks for reading my mail and for suggestions...
> I am assuming there is no simple fix to teach
> McStas to respond in a more 'natural' way...
>
> Thanks!
>
> Uli
> --
> Ulrich WILDGRUBER
> wildgrub at dxray.mpi-stuttgart.mpg.de
> wwwmf.mpi-stuttgart.mpg.de/abteilungen/dosch/dosch.html
> -----------------------------------------------------------------------------
> Max-Planck-Institut für Metallforschung | Technische Universität München
> Heisenbergstr. 3 | ZWE Neue Forschungs-Neutronenquelle
> | Instrumentierung
> D-70569 Stuttgart | D-85747 Garching/München
> Tel.: (+49)-711-689-1900 | Tel.: (+49)-89-289-14681
> Fax.: (+49)-711-689-1902 | Fax.: (+49)-89-289-14666
>
> _______________________________________________
> neutron-mc mailing list
> neutron-mc at risoe.dk
> http://neutron.risoe.dk/mailman/listinfo/neutron-mc
--
What's up Doc ?
--------------------------------------------
Emmanuel FARHI, http://www.ill.fr/Computing/people/Farhi \|/ ____ \|/
CS-Group ILL4/156, 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 20 76 48 \__U_/
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