/*******************************************************************************
*         McStas instrument definition URL=http://www.mcstas.org
*
* Instrument: Test_Radial_div
*
* %Identification
* Written by: P. Willendrup
* Date: 20. October 2026
* Origin: DTU
* %INSTRUMENT_SITE: Tests_monitors
*
* Test of the contributed Radial_div monitor
*
* %Description
* A small, weakly divergent beam is recorded by a PSD_monitor and by a Radial_div
* monitor of the same size. With the beam divergence well within maxdiv_r and
* all wavelengths within [Lmin, Lmax], both monitors record the same intensity.
* Narrowing [Lmin, Lmax] makes Radial_div count only part of the beam.
*
* %Example: Test_Radial_div.instr Lmin=0.5 Lmax=10 Detector: PSD_I=0.000100531
* %Example: Test_Radial_div.instr Lmin=0.5 Lmax=10 Detector: RadDiv_I=0.000100531
* %Example: Test_Radial_div.instr Lmin=4 Lmax=6 Detector: RadDiv_I=2.51059e-05
*
* %Parameters
* Lmin:     [AA] Minimum wavelength counted by Radial_div
* Lmax:     [AA] Maximum wavelength counted by Radial_div
* maxdiv_r: [deg] Maximal radial divergence counted by Radial_div
*
* %End
*******************************************************************************/
DEFINE INSTRUMENT Test_Radial_div(Lmin=0.5, Lmax=10, maxdiv_r=2)

TRACE

COMPONENT Origin = Progress_bar()
AT (0, 0, 0) ABSOLUTE

COMPONENT Source = Source_simple(radius=0.01, dist=10, focus_xw=0.02, focus_yh=0.02, lambda0=5, dlambda=4)
AT (0, 0, 0) RELATIVE Origin

COMPONENT PSD = PSD_monitor(xwidth=0.04, yheight=0.04, nx=40, ny=40, filename="psd.dat", restore_neutron=1)
AT (0, 0, 10) RELATIVE Source

COMPONENT RadDiv = Radial_div(xwidth=0.04, yheight=0.04, ndiv=20, maxdiv_r=maxdiv_r, Lmin=Lmin, Lmax=Lmax, filename="raddiv.dat", restore_neutron=1)
AT (0, 0, 10) RELATIVE Source

END