/******************************************************************************
*         McStas instrument definition URL=http://www.mcstas.org
*
* Instrument: Mezei_SNS_decoupled_poisoned.instr
*
* %I
* Written by: Peter Willendrup <pkwi@fysik.dtu.dk>
* Date: May 2913
* Origin: DTU Physics
*
* %INSTRUMENT_SITE: SNS
*
* Simple instrumentfile for estimating SNS brilliance, moderator is a rescaled ESS short-pulsed Mezei description.
*
* %DESCRIPTION
*
* Simple instrumentfile for estimating SNS brilliance, moderator is a rescaled ESS short-pulsed Mezei description.
*
* %Example: -y Detector: Brillmon_I=1.178e+13
*
* %Parameters
* Lambda_min: [AA] Minimum wavelength produced at source
* Lambda_max: [AA] Maximum wavelength produced at source
*
* %Link
*
* %End
*******************************************************************************/
DEFINE INSTRUMENT Mezei_SNS_decoupled_poisoned(Lambda_min=0.5,Lambda_max=20)

/* The DECLARE section allows us to declare variables or  small      */
/* functions in C syntax. These may be used in the whole instrument. */

DECLARE
%{
  double E_min;
  double E_max;
%}

INITIALIZE
%{
  E_min=81.82/(Lambda_max*Lambda_max);
  E_max=81.82/(Lambda_min*Lambda_min);
%}

/* Here comes the TRACE section, where the actual      */
/* instrument is defined as a sequence of components.  */
TRACE

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

COMPONENT Source = ESS_moderator_short(size=0.01,
				       dist=1, focus_xw=0.01, focus_yh=0.01, Lmin=Lambda_min, Lmax=Lambda_max, nu=60, T=50, tau=49e-6, tau1=0, tau2=7e-6, n=5, n2=5, chi2=0.9,
		    I0=2.7e10, I2=4.6e10, branch1=0, branch2=0.5, branchframe=1)
   AT (0,0,0) RELATIVE Origin
EXTEND %{
  /* Cold moderator is downstream @ SNS, was designed to be upstream at ESS */
  p/=1.3;
  /* 5MW to 1.4MW */
  p/=5;
  p*=1.4;
%}

COMPONENT Brillmon = Brilliance_monitor(
    nlam = 196, nt = 1201, filename = "brill", t_0 = 0,
    t_1 = 1200, lambda_0 = Lambda_min, lambda_1 = Lambda_max,
    Freq =60.0)
  AT (0, 0, 0.0000001) RELATIVE Source

/* This section is executed when the simulation ends (C code). Other    */
/* optional sections are : SAVE                                         */
/* The END token marks the instrument definition end */
END