/*******************************************************************************
*
* McStas, neutron ray-tracing package
*         Copyright 1997-2002, All rights reserved
*         Risoe National Laboratory, Roskilde, Denmark
*         Institut Laue Langevin, Grenoble, France
*
* Component: TOF_cylPSD_monitor
*
* %I
* Written by:  Kim Lefmann
* Date: October 2000
* Version: $Revision: 1.12 $
* Origin: Risoe
* Release: McStas 1.6
* Modified by: Kim Lefmann, October 9, 2001 
*
* Cylindrical (2pi) PSD Time-of-flight monitor.
*
* %P
* INPUT PARAMETERS:
*
* radius:   Cylinder radius (m)
* height:   Cylinder height (m)
* nt:    Number of time bins (1)
* t_0:      Beginning of time window (mu-s)
* t_1:      End of time window (mu-s)
* nphi:     Number of angular bins (deg)     
* filename: Name of file in which to store the detector image (text)
*
* OUTPUT PARAMETERS:
*
* TOF_N:    Array of neutron counts
* TOF_p:    Array of neutron weight counts
* TOF_p2:   Array of second moments
* 
* %E
*******************************************************************************/

DEFINE COMPONENT TOF_cylPSD_monitor
DEFINITION PARAMETERS (nt, filename, nphi) 
SETTING PARAMETERS (radius, height, t_0, t_1)
OUTPUT PARAMETERS (TOF_N, TOF_p, TOF_p2)
STATE PARAMETERS (x,y,z,vx,vy,vz,t,s1,s2,p)
DECLARE
  %{
    double TOF_N[nt][nphi];
    double TOF_p[nt][nphi];
    double TOF_p2[nt][nphi];
    double binphi, tt_0, tt_1;
  %}
INITIALIZE
  %{
    int i,j;

    tt_0=t_0*1e-6;
    tt_1=t_1*1e-6;
    for (i=0; i<nt; i++)
      for (j=0; j<nphi; j++)
      {
        TOF_N[i][j] = 0;
        TOF_p[i][j] = 0;
        TOF_p2[i][j] = 0;
      }
    binphi=360.0/(double)nphi;
  
  %}
TRACE
  %{
    int i,j;
    double cyl_t0,cyl_t1,dt,phi;

    if(!cylinder_intersect(&cyl_t0, &cyl_t1, x,y,z,vx,vy,vz, radius, height)) 
     /* No hit */ 
      ABSORB;
    if(cyl_t0>0)  /* Neutron hits cylinder from the outside */
      ABSORB;
    dt=cyl_t1;
    PROP_DT(dt);
    if(y>=height/2 || y<= -height/2) 
      ABSORB;  /* Neutron hits cylinder ends; no detectors here */    

    i = floor((t-tt_0)*nt/(tt_1-tt_0));              /* Bin number */

    if (i < 0 || i >= nt)        /* Do not detect */
    {
    }
    else
     {
      phi = atan2(x,z);
      j = floor((double)nphi/2.0 + RAD2DEG*phi/(double)binphi);
      TOF_N[i][j]++;
      TOF_p[i][j] += p;
      TOF_p2[i][j] += p*p;
     }
  %}
SAVE
  %{
    DETECTOR_OUT_2D(
        "Cylindrical Time-of-flight PSD monitor",
        "Time-of-flight [\\gms]",
        "Angle [deg]",
        t_0, t_1, -180, 180, 
        nt, nphi,
        &TOF_N[0][0],&TOF_p[0][0],&TOF_p2[0][0],
        filename);
  %}

MCDISPLAY
%{
  magnify("y");
  circle("xz", 0,0,0,radius);
%}

END



















































