Emc_helix Class Reference

#include <Emc_helix.h>

Public Member Functions
	Emc_helix (void)
	~Emc_helix (void)
int	Emc_Get (double, int, double[])
void	debugOpt (int deb)
void	pathlCut (double pathl_max)
void	zemcCut (double zemc_min, double zemc_max)

Public Attributes
double	R_emc
double	Fi_emc
double	W_emc
double	Z_emc
double	theta_emc
double	phi_emc
double	Dr
double	Phi0
double	Kappa
double	Dz
double	Tanl
int	NTrk
double	Phi1

Detailed Description

Definition at line 16 of file Emc_helix.h.

Constructor & Destructor Documentation

Emc_helix()

Emc_helix::Emc_helix

(

void

)

Definition at line 58 of file Emc_helix.cxx.

                         {
   piby1=3.141593;
   pi2=2.0*piby1;
   _debug=0;
   _pathl_cut= 1000.0;
  
 }

~Emc_helix()

Emc_helix::~Emc_helix ( void )

inline

Definition at line 22 of file Emc_helix.h.

{};

Member Function Documentation

debugOpt()

void Emc_helix::debugOpt ( int deb )

inline

Definition at line 41 of file Emc_helix.h.

                           {
      _debug = deb;
    }

Emc_Get()

int Emc_helix::Emc_Get	(	double	rEmc,
		int	id,
		double	fzisan[] )

Definition at line 67 of file Emc_helix.cxx.

                                                           {
   // crossing points of the helix on the Emc cylinder
   double xc,yc;            // center of the circle
   double rho;              // radius of emc  cyclinder
   double  xx[2],yy[2];      // coordinates of hits
   double  emcx,emcy;        // (x,y) on the radius of R_emc
   double  nx,ny;            // direction cosines of mom vector at vertex
   double  cosx,sinx;
   double aa,ca,cb,cc,detm;
  
   
   // fzisan track ID and EMC radius
   int Id_cdfztrk = id; R_emc = rEmc;
 
   if( Id_cdfztrk<0 ) {
     if (_debug) std::cout << " Emc_helix *** wrong id_cdfztrk ="
               << Id_cdfztrk << std::endl;
                                                  return(-1);
   }
   
   // fzisan track
   /*    FTFinder * ftrk = FTFinder:: GetPointer();
   FTList<FTTrack *> & FsTrks = ftrk->tracks();
   NTrk = FsTrks.length();
     
   if (NTrk<=0)                                   return (-3);
 
   // get helix params for Id_cdfztrk 
   FTTrack & trk = * FsTrks[Id_cdfztrk];
   const Helix hel = * trk.helix();
 
   const HepPoint3D pivot1(0.,0.,0.);
   HepVector  a(5,0);
   a[0] = hel.a()[0];
   a[1] = hel.a()[1];
   a[2] = hel.a()[2];
   a[3] = hel.a()[3];
   a[4] = hel.a()[4];
   */
   const HepPoint3D pivot1(0.,0.,0.);
   HepVector  a(5,0);
   a[0] = fzisan[0];
   a[1] = fzisan[1];
   a[2] = fzisan[2];
   a[3] = fzisan[3];
   a[4] = fzisan[4];
 
   // Ill-fitted track in fzisan (dz=tanl=-9999.)
   if (abs(a[3])>50.0 || abs(a[4])>500.0)          return (-5);
 
   // D e f i n e   h e l i x
   Helix helix1(pivot1,a);
   Dr    = helix1.a()[0];   
   Phi0  = helix1.a()[1];   
   Kappa = helix1.a()[2];    
   Dz    = helix1.a()[3];   
   Tanl  = helix1.a()[4];
 
   /* double detaphi=asin(0.5*0.81*0.3*fabs(Kappa));
      double phi=Phi0+detaphi+ piby1/2;
      */
    
   // check cdfztrk hit on Emc cyclinder
   rho  = helix1.radius(); 
   // cout<<" Emc_helix:: rho  ="<<rho<<endl;  // radius of the circle in cm
   HepPoint3D    xyz    = helix1.center();
   xc   = xyz(0);
   yc   = xyz(1);
 
   Hep3Vector vxyz   = helix1.direction();
   nx   = vxyz(0);              // direction of track at the vertex
   ny   = vxyz(1); 
   
   // get hit on Emc cylinder at radius R_Emc;
   if( xc==0.0 && yc==0.0 ) return(-3);
   
   // coefficients of quadratic equation
   ca = xc*xc + yc*yc ;
   aa = 0.5 * ( ca - rho*rho + R_emc*R_emc );
   
   if ( xc != 0.0 ) {
      cb = aa * yc;
      cc = aa*aa - R_emc*R_emc*xc*xc; 
      // determinant
      detm = cb*cb - ca*cc;
      if ( detm > 0.0 ) {
     yy[0] = ( cb + sqrt(detm) )/ ca;
     xx[0] = ( aa - yy[0]*yc )/xc;
     yy[1] = ( cb - sqrt(detm) )/ ca;
     xx[1] = ( aa - yy[1]*yc )/xc;
      } else  return(-1);
   }
   else{
      cb = aa * xc;
      cc = aa*aa - R_emc*R_emc*yc*yc;
      // determinant
      detm = cb*cb - ca*cc;
      if ( detm > 0.0 ) {
     xx[0] = ( cb + sqrt(detm) )/ca;
     yy[0] = ( aa - xx[0]*xc )/yc;
     xx[1] = ( cb - sqrt(detm) )/ca;
     yy[1] = ( aa - xx[1]*xc )/yc;
      } else return(-2);
   }
  
 
   // choose one of hits according to track direction at the vertex.
  
  if( xx[0]*nx + yy[0]*ny > 0.0 ) { emcx = xx[0]; emcy = yy[0]; }
   else                            { emcx = xx[1]; emcy = yy[1]; }
    
   double fi = atan2(emcy ,emcx );    // atna2 from -pi to pi
 
    if( fi < 0.0 ) fi=pi2+fi;
   Fi_emc = fi;         
     
   // get phi and z on the emc counter
   const HepPoint3D pivot2( emcx, emcy, 0.0);
   helix1.pivot(pivot2);
   
   // corrected by Ozaki san to avoid negative path length on Aug.10,99   
   Phi1=helix1.a()[1];
   Z_emc=helix1.a()[3];
 
   //get(thepa,phi)from the intersection (x,y,z)
   Hep3Vector intersec(emcx, emcy, Z_emc);
    theta_emc = intersec.getTheta();
    phi_emc = intersec.getPhi();
  
   return(1);
 
}

Referenced by EsTimeAlg::execute().

pathlCut()

void Emc_helix::pathlCut ( double pathl_max )

inline

Definition at line 45 of file Emc_helix.h.

                                    {
      _pathl_cut = pathl_max;
    }

Referenced by EsTimeAlg::execute().

zemcCut()

void Emc_helix::zemcCut ( double zemc_min, double zemc_max )

inline

Definition at line 49 of file Emc_helix.h.

                                                   {
      _zemc_cutm = zemc_min;
      _zemc_cutx = zemc_max;
    }

Member Data Documentation

Dr

double Emc_helix::Dr

Definition at line 34 of file Emc_helix.h.

Referenced by Emc_Get().

Dz

double Emc_helix::Dz

Definition at line 34 of file Emc_helix.h.

Referenced by Emc_Get().

Fi_emc

double Emc_helix::Fi_emc

Definition at line 27 of file Emc_helix.h.

Referenced by Emc_Get().

Kappa

double Emc_helix::Kappa

Definition at line 34 of file Emc_helix.h.

Referenced by Emc_Get().

NTrk

int Emc_helix::NTrk

Definition at line 35 of file Emc_helix.h.

Phi0

double Emc_helix::Phi0

Definition at line 34 of file Emc_helix.h.

Referenced by Emc_Get().

Phi1

double Emc_helix::Phi1

Definition at line 36 of file Emc_helix.h.

Referenced by Emc_Get().

phi_emc

double Emc_helix::phi_emc

Definition at line 31 of file Emc_helix.h.

Referenced by Emc_Get(), and EsTimeAlg::execute().

R_emc

double Emc_helix::R_emc

Definition at line 26 of file Emc_helix.h.

Referenced by Emc_Get().

Tanl

double Emc_helix::Tanl

Definition at line 34 of file Emc_helix.h.

Referenced by Emc_Get().

theta_emc

double Emc_helix::theta_emc

Definition at line 30 of file Emc_helix.h.

Referenced by Emc_Get(), and EsTimeAlg::execute().

W_emc

double Emc_helix::W_emc

Definition at line 28 of file Emc_helix.h.

Z_emc

double Emc_helix::Z_emc

Definition at line 29 of file Emc_helix.h.

Referenced by Emc_Get(), and EsTimeAlg::execute().

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The documentation for this class was generated from the following files:

• Emc_helix.h
• Emc_helix.cxx