#include <phaseSpaceIntegrals.h>

Public Member Functions
	PhaseSpaceIntegral4body ()

double	getVal (const DalitzEventPattern &_pat)

double	getVal (double mum, double d1, double d2, double d3, double d4)

double	getValCheck (const DalitzEventPattern &_pat)

double	getValCheck (double mum, double d1, double d2, double d3, double d4)

Static Protected Attributes
static TF1 *	_f = 0

Detailed Description

Definition at line 49 of file phaseSpaceIntegrals.h.

Constructor & Destructor Documentation

◆ PhaseSpaceIntegral4body()

PhaseSpaceIntegral4body::PhaseSpaceIntegral4body ( )

Definition at line 246 of file phaseSpaceIntegrals.cpp.

                                                 {
   if(0 == _f){
     _f = new TF1("d4body_by_ds12", d4body_by_ds12
          , 0, 10*GeV*GeV
          , 5
          );
   }
   if(0 == _f){
     cout << "phaseSpaceIntegral4body::phaseSpaceIntegral3body()"
      << " failed to get TF1!!!" << endl;
   }
 }

Member Function Documentation

◆ getVal() [1/2]

double PhaseSpaceIntegral4body::getVal ( const DalitzEventPattern & _pat )

Definition at line 260 of file phaseSpaceIntegrals.cpp.

                                                                     {
   if(_pat.size() != 5){
     cout << "phaseSpaceIntegral4body: wrong pattern " << _pat << endl;
   }
   double mum = _pat[0].mass();
   double d1  = _pat[1].mass();
   double d2  = _pat[2].mass();
   double d3  = _pat[3].mass();
   double d4  = _pat[4].mass();
   return getVal(mum, d1, d2, d3, d4);
 }

◆ getVal() [2/2]

double PhaseSpaceIntegral4body::getVal	(	double	mum,
		double	d1,
		double	d2,
		double	d3,
		double	d4
	)

Definition at line 271 of file phaseSpaceIntegrals.cpp.

                                               {
 
   bool dbThis = false;
 
   double min_m12 = (d1 + d2);
   double max_m12 = (mum - d3 - d4);
   if(dbThis)cout << "PhaseSpaceIntegral4body::getVal : from, to " 
          << min_m12 << ", " << max_m12 << endl;
   if(min_m12 >= max_m12) return 0;
 
   double min_s12 = min_m12*min_m12;
   double max_s12 = max_m12*max_m12;
 
   Double_t para[5]={mum, d1, d2, d3, d4};
 
   _f->SetParameters(para);
 
   Int_t np = 1000;
   double xpts[1000];
   double wpts[1000];
   _f->CalcGaussLegendreSamplingPoints(np,xpts,wpts,1e-15);
   return _f->IntegralFast(np,xpts,wpts, min_s12, max_s12, para);
   //  return _f->Integral(min_s12, max_s12, para);
 }

◆ getValCheck() [1/2]

double PhaseSpaceIntegral4body::getValCheck ( const DalitzEventPattern & _pat )

Definition at line 297 of file phaseSpaceIntegrals.cpp.

                                                                          {
   if(_pat.size() != 5){
     cout << "phaseSpaceIntegral4body: wrong pattern " << _pat << endl;
   }
   double mum = _pat[0].mass();
   double d1  = _pat[1].mass();
   double d2  = _pat[2].mass();
   double d3  = _pat[3].mass();
   double d4  = _pat[4].mass();
   return getValCheck(mum, d1, d2, d3, d4);
 }

◆ getValCheck() [2/2]

double PhaseSpaceIntegral4body::getValCheck	(	double	mum,
		double	d1,
		double	d2,
		double	d3,
		double	d4
	)

Definition at line 308 of file phaseSpaceIntegrals.cpp.

                                     {
   
   bool dbThis = false;
 
   double min_m12 = (d1 + d2);
   double max_m12 = (mum - d3 - d4);
   if(dbThis)cout << "PhaseSpaceIntegral4body::getVal : from, to " 
          << min_m12 << ", " << max_m12 << endl;
   if(min_m12 >= max_m12) return 0;
 
   double min_s12 = min_m12*min_m12;
   double max_s12 = max_m12*max_m12;
 
   Double_t para[5]={mum, d1, d2, d3, d4};
 
   _f->SetParameters(para);
 
   int NSteps = 10000;
   double sum = 0;
   double dx = (max_s12 - min_s12)/((double)NSteps);
   
   for(int i=0; i< NSteps; i++){
     double dim = 0.5 + (double) i;
     double x = min_s12 + dx*dim;
     sum += _f->Eval(x);
   }
   return sum*dx;
 }