/*******************************************************************************
*         McStas, neutron ray-tracing package
*
* Instrument: Unittest_PROP_NO_G
*
* %Identification
* Written by: Mads Bertelsen
* Date: September 2026
* Origin: ESS
* %INSTRUMENT_SITE: Tests_grammar
*
* Test for the PROP_NO_G_DT propagation macro.
*
* %Description
* A long-wavelength beam is focused onto a small detector 10 m away. The
* intermediate Arm uses PROP_NO_G_DT, so the beam should remain focused even
* when gravity is enabled.
*
* %Example: -g Detector: PropNoGMonitor_I=7.95774e-8
*
* %End
*******************************************************************************/
DEFINE INSTRUMENT Unittest_PROP_NO_G()

TRACE

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

COMPONENT Source = Source_simple(
    radius = 0.01,
    dist = 10,
    focus_xw = 0.01,
    focus_yh = 0.01,
    lambda0 = 30,
    dlambda = 0,
    flux = 0)
  AT (0, 0, 0) RELATIVE Origin

COMPONENT PropNoG = Arm()
  AT (0, 0, 0) RELATIVE Source
EXTEND %{
  PROP_NO_G_DT(10/vz);
%}

COMPONENT PropNoGMonitor = Monitor(
    xwidth = 0.01,
    yheight = 0.01)
  AT (0, 0, 10) RELATIVE PropNoG

END