[u/mrichter/AliRoot.git] / TEvtGen / EvtGenBase / EvtPto3PAmpFactory.cxx

//-----------------------------------------------------------------------
// File and Version Information: 
//      $Id: EvtPto3PAmpFactory.cc,v 1.22 2009/02/19 03:22:30 ryd Exp $
// 
// Environment:
//      This software is part of the EvtGen package developed jointly
//      for the BaBar and CLEO collaborations. If you use all or part
//      of it, please give an appropriate acknowledgement.
//
// Copyright Information:
//      Copyright (C) 1998 Caltech, UCSB
//
// Module creator:
//      Alexei Dvoretskii, Caltech, 2001-2002.
//-----------------------------------------------------------------------
#include "EvtGenBase/EvtPatches.hh"

// AmpFactory for building a P -> 3P decay
// (pseudoscalar to three pseudoscalars)

#include <assert.h>
#include <math.h>
#include <stdio.h>
#include <stdlib.h>

#include "EvtGenBase/EvtId.hh"
#include "EvtGenBase/EvtPDL.hh"
#include "EvtGenBase/EvtConst.hh"
#include "EvtGenBase/EvtComplex.hh"
#include "EvtGenBase/EvtCyclic3.hh"
#include "EvtGenBase/EvtSpinType.hh"
#include "EvtGenBase/EvtPto3PAmp.hh"
#include "EvtGenBase/EvtNonresonantAmp.hh"
#include "EvtGenBase/EvtFlatAmp.hh"
#include "EvtGenBase/EvtLASSAmp.hh"
#include "EvtGenBase/EvtPto3PAmpFactory.hh"
#include "EvtGenBase/EvtPropBreitWigner.hh"
#include "EvtGenBase/EvtPropFlatte.hh"
#include "EvtGenBase/EvtPropBreitWignerRel.hh"
#include "EvtGenBase/EvtDalitzResPdf.hh"
#include "EvtGenBase/EvtDalitzFlatPdf.hh"

using namespace EvtCyclic3;
#include <iostream>

void EvtPto3PAmpFactory::processAmp(EvtComplex c, std::vector<std::string> vv, bool conj)
{
  if(_verbose) {
    
    printf("Make %samplitude\n",conj ? "CP conjugate" : "");
    unsigned i;
    for(i=0;i<vv.size();i++) printf("%s\n",vv[i].c_str());
    printf("\n");
  }
  
  EvtAmplitude<EvtDalitzPoint>* amp = 0;
  EvtPdf<EvtDalitzPoint>* pdf = 0;
  std::string name;
  Pair pairRes=AB;

  size_t i;
  /*
         Experimental amplitudes
  */
  if(vv[0] == "PHASESPACE") {
    
    pdf = new EvtDalitzFlatPdf(_dp);
    amp = new EvtFlatAmp<EvtDalitzPoint>();
    name = "NR";
  }
  else if (!vv[0].find("NONRES")) {
    double alpha=0;
    EvtPto3PAmp::NumType typeNRes=EvtPto3PAmp::NONRES;
    if      (vv[0]=="NONRES_LIN") {
      typeNRes=EvtPto3PAmp::NONRES_LIN;
      pairRes=strToPair(vv[1].c_str());
    }
    else if (vv[0]=="NONRES_EXP") {
      typeNRes=EvtPto3PAmp::NONRES_EXP;
      pairRes = strToPair(vv[1].c_str());
      alpha   = strtod(vv[2].c_str(),0);
    }
    else assert(0);
    pdf = new EvtDalitzFlatPdf(_dp);
    amp = new EvtNonresonantAmp( &_dp, typeNRes, pairRes, alpha);  
  }
  else if (vv[0]=="LASS") {
    pairRes = strToPair(vv[1].c_str());
    double m0 = strtod(vv[2].c_str(),0);
    double g0 = strtod(vv[3].c_str(),0);
    double a  = strtod(vv[4].c_str(),0);
    double r  = strtod(vv[5].c_str(),0);
    double cutoff  = strtod(vv[6].c_str(),0);
    pdf = new EvtDalitzResPdf(_dp,m0,g0,pairRes);
    amp = new EvtLASSAmp( &_dp, pairRes, m0, g0, a, r, cutoff);
  }

  /*
      Resonant amplitudes
  */
  else if(vv[0] == "RESONANCE") {
    EvtPto3PAmp* partAmp = 0;
      
    // RESONANCE stanza
    
    pairRes = strToPair(vv[1].c_str());
    EvtSpinType::spintype spinR;
    double mR, gR;      
    name = vv[2];
    EvtId resId = EvtPDL::getId(vv[2]);
    if(_verbose) printf("Particles %s form %sresonance %s\n",
			vv[1].c_str(),vv[2].c_str(), conj ? "(conj) " : "");

    // If no valid particle name is given, assume that 
    // it is the spin, the mass and the width of the particle.
      
    if(resId.getId() == -1) {
	
      switch(atoi(vv[2].c_str())) {
	
      case 0: { spinR = EvtSpinType::SCALAR; break; }
      case 1: { spinR = EvtSpinType::VECTOR; break; }
      case 2: { spinR = EvtSpinType::TENSOR; break; }
      case 3: { spinR = EvtSpinType::SPIN3; break; }
      case 4: { spinR = EvtSpinType::SPIN4; break; }
      default: { assert(0); break; }
      }
	
      mR = strtod(vv[3].c_str(),0);
      gR = strtod(vv[4].c_str(),0);
      i = 4;
    }
    else {
      
      // For a valid particle get spin, mass and width
      
      spinR = EvtPDL::getSpinType(resId);
      mR = EvtPDL::getMeanMass(resId);
      gR = EvtPDL::getWidth(resId);
      i = 2;
      
      // It's possible to specify mass and width of a particle 
      // explicitly
      
      if(vv[3] != "ANGULAR") {
	
	if(_verbose) 
	  printf("Setting m(%s)=%s g(%s)=%s\n",
		 vv[2].c_str(),vv[3].c_str(),vv[2].c_str(),vv[4].c_str());

	mR = strtod(vv[3].c_str(),0);
	gR = strtod(vv[4].c_str(),0);
	i = 4;
      }
    }
    
    // ANGULAR stanza
    
    if(vv[++i] != "ANGULAR") {

      printf("%s instead of ANGULAR\n",vv[i].c_str());
      exit(0);
    }
    Pair pairAng = strToPair(vv[++i].c_str());
    if(_verbose) printf("Angle is measured between particles %s\n",vv[i].c_str());
      
    // TYPE stanza
    
    assert(vv[++i] == "TYPE");
    std::string type = vv[++i];
    if(_verbose) printf("Propagator type %s\n",vv[i].c_str());
    
    if(type == "NBW") {      

      EvtPropBreitWigner prop(mR,gR);
      partAmp = new EvtPto3PAmp(_dp,pairAng,pairRes,spinR,prop,EvtPto3PAmp::NBW);
    }
    else if(type == "RBW_ZEMACH") {
      
      EvtPropBreitWignerRel prop(mR,gR);
      partAmp = new EvtPto3PAmp(_dp,pairAng,pairRes,spinR,prop,EvtPto3PAmp::RBW_ZEMACH);
    }
    else if(type == "RBW_KUEHN") {
      
      EvtPropBreitWignerRel prop(mR,gR);
      partAmp = new EvtPto3PAmp(_dp,pairAng,pairRes,spinR,prop,EvtPto3PAmp::RBW_KUEHN);
    }
    else if(type == "RBW_CLEO") {
      
      EvtPropBreitWignerRel prop(mR,gR);
      partAmp = new EvtPto3PAmp(_dp,pairAng,pairRes,spinR,prop,EvtPto3PAmp::RBW_CLEO);
    }     
    else if(type == "FLATTE") {
      
      double m1a = _dp.m( first(pairRes) );
      double m1b = _dp.m( second(pairRes) );    
      // 2nd channel
      double g2  = strtod(vv[++i].c_str(),0);
      double m2a = strtod(vv[++i].c_str(),0);
      double m2b = strtod(vv[++i].c_str(),0);
      EvtPropFlatte  prop( mR, gR, m1a, m1b, g2, m2a, m2b );
      partAmp = new EvtPto3PAmp(_dp,pairAng,pairRes,spinR,prop,EvtPto3PAmp::FLATTE);
    }
    else assert(0);
      
    // Optional DVFF, BVFF stanzas
    
    if(i < vv.size() - 1) {
      if(vv[i+1] == "DVFF") {	
	i++;
	if(vv[++i] == "BLATTWEISSKOPF") {
	  
	  double R = strtod(vv[++i].c_str(),0);
	  partAmp->set_fd(R);
	}
	else assert(0);
      }
    }
      
    if(i < vv.size() - 1) {
      if(vv[i+1] == "BVFF") {	
	i++;
	if(vv[++i] == "BLATTWEISSKOPF") {

	  if(_verbose) printf("BVFF=%s\n",vv[i].c_str());
	  double R = strtod(vv[++i].c_str(),0);
	  partAmp->set_fb(R);
	}
	else assert(0);
      }
    }

    const int minwidths=5;
    //Optional resonance minimum and maximum
    if(i < vv.size() - 1) {
      if(vv[i+1] == "CUTOFF") {	
	i++;
	if(vv[i+1] == "MIN") {
	  i++;
	  double min = strtod(vv[++i].c_str(),0);
	  if(_verbose) std::cout<<"CUTOFF MIN = "<<min<<std::endl;
	  //ensure against cutting off too close to the resonance
	  assert( min<(mR-minwidths*gR) );
	  partAmp->setmin(min);
	}
	else if (vv[i+1] == "MAX") {
	  i++;
	  double max = strtod(vv[++i].c_str(),0);
	  if(_verbose) std::cout<<"CUTOFF MAX = "<<max<<std::endl;
	  //ensure against cutting off too close to the resonance
	  assert( max>(mR+minwidths*gR) );
	  partAmp->setmax(max);
	}
	else assert(0);
      }
    }

    //2nd iteration in case min and max are both specified
    if(i < vv.size() - 1) {
      if(vv[i+1] == "CUTOFF") {	
	i++;
	if(vv[i+1] == "MIN") {
	  i++;
	  double min = strtod(vv[++i].c_str(),0);
	  if(_verbose) std::cout<<"CUTOFF MIN = "<<min<<std::endl;
	  //ensure against cutting off too close to the resonance
	  assert( min<(mR-minwidths*gR) );
	  partAmp->setmin(min);
	}
	else if (vv[i+1] == "MAX") {
	  i++;
	  double max = strtod(vv[++i].c_str(),0);
	  if(_verbose) std::cout<<"CUTOFF MAX = "<<max<<std::endl;
	  //ensure against cutting off too close to the resonance
	  assert( max>(mR+minwidths*gR) );
	  partAmp->setmax(max);
	}
	else assert(0);
      }
    }


    i++;
    
    pdf = new EvtDalitzResPdf(_dp,mR,gR,pairRes);
    amp = partAmp;
  }

  assert(amp);
  assert(pdf);

  if(!conj) {
    _amp->addOwnedTerm(c,amp);
  }
  else {
    _ampConj->addOwnedTerm(c,amp);
  }

  double scale = matchIsobarCoef(_amp, pdf, pairRes);
  _pc->addOwnedTerm(abs2(c)*scale,pdf);

  _names.push_back(name);
}
  
double EvtPto3PAmpFactory::matchIsobarCoef(EvtAmplitude<EvtDalitzPoint>* amp,
					   EvtPdf<EvtDalitzPoint>* pdf, 
					   EvtCyclic3::Pair ipair) {

  // account for differences in the definition of amplitudes by matching 
  //        Integral( c'*pdf ) = Integral( c*|A|^2 ) 
  // to improve generation efficiency ...

  double Ipdf  = pdf->compute_integral(10000).value();
  double Iamp2 = 0;


  EvtCyclic3::Pair jpair = EvtCyclic3::next(ipair);
  EvtCyclic3::Pair kpair = EvtCyclic3::next(jpair);

  // Trapezoidal integral
  int N=10000;
  
  double di = (_dp.qAbsMax(ipair) - _dp.qAbsMin(ipair))/((double) N);
  
  double siMin = _dp.qAbsMin(ipair);
  
  double s[3]; // playing with fire
  for(int i=1; i<N; i++) {
    
    s[ipair] = siMin + di*i;
    s[jpair] = _dp.q(jpair, 0.9999, ipair, s[ipair]);    
    s[kpair] = _dp.bigM()*_dp.bigM() - s[ipair] - s[jpair]
      + _dp.mA()*_dp.mA() + _dp.mB()*_dp.mB() + _dp.mC()*_dp.mC();
    
    EvtDalitzPoint point( _dp.mA(), _dp.mB(), _dp.mC(), 
			  s[EvtCyclic3::AB], s[EvtCyclic3::BC], s[EvtCyclic3::CA]);
    
    if (!point.isValid()) continue;
    
    double p = point.p(other(ipair), ipair);
    double q = point.p(first(ipair), ipair);
    
    double itg = abs2( amp->evaluate(point) )*di*4*q*p;
    Iamp2 += itg;
    
  }
  if (_verbose) std::cout << "integral = " << Iamp2 << "  pdf="<<Ipdf << std::endl;
  
  assert(Ipdf>0 && Iamp2>0);
  
  return Iamp2/Ipdf;
}
Commit	Line	Data
da0e9ce3	1	//-----------------------------------------------------------------------
	2	// File and Version Information:
	3	// $Id: EvtPto3PAmpFactory.cc,v 1.22 2009/02/19 03:22:30 ryd Exp $
	4	//
	5	// Environment:
	6	// This software is part of the EvtGen package developed jointly
	7	// for the BaBar and CLEO collaborations. If you use all or part
	8	// of it, please give an appropriate acknowledgement.
	9	//
	10	// Copyright Information:
	11	// Copyright (C) 1998 Caltech, UCSB
	12	//
	13	// Module creator:
	14	// Alexei Dvoretskii, Caltech, 2001-2002.
	15	//-----------------------------------------------------------------------
	16	#include "EvtGenBase/EvtPatches.hh"
	17
	18	// AmpFactory for building a P -> 3P decay
	19	// (pseudoscalar to three pseudoscalars)
	20
	21	#include <assert.h>
	22	#include <math.h>
	23	#include <stdio.h>
	24	#include <stdlib.h>
	25
	26	#include "EvtGenBase/EvtId.hh"
	27	#include "EvtGenBase/EvtPDL.hh"
	28	#include "EvtGenBase/EvtConst.hh"
	29	#include "EvtGenBase/EvtComplex.hh"
	30	#include "EvtGenBase/EvtCyclic3.hh"
	31	#include "EvtGenBase/EvtSpinType.hh"
	32	#include "EvtGenBase/EvtPto3PAmp.hh"
	33	#include "EvtGenBase/EvtNonresonantAmp.hh"
	34	#include "EvtGenBase/EvtFlatAmp.hh"
	35	#include "EvtGenBase/EvtLASSAmp.hh"
	36	#include "EvtGenBase/EvtPto3PAmpFactory.hh"
	37	#include "EvtGenBase/EvtPropBreitWigner.hh"
	38	#include "EvtGenBase/EvtPropFlatte.hh"
	39	#include "EvtGenBase/EvtPropBreitWignerRel.hh"
	40	#include "EvtGenBase/EvtDalitzResPdf.hh"
	41	#include "EvtGenBase/EvtDalitzFlatPdf.hh"
	42
	43	using namespace EvtCyclic3;
	44	#include <iostream>
	45
	46	void EvtPto3PAmpFactory::processAmp(EvtComplex c, std::vector<std::string> vv, bool conj)
	47	{
	48	if(_verbose) {
	49
	50	printf("Make %samplitude\n",conj ? "CP conjugate" : "");
	51	unsigned i;
	52	for(i=0;i<vv.size();i++) printf("%s\n",vv[i].c_str());
	53	printf("\n");
	54	}
	55
	56	EvtAmplitude<EvtDalitzPoint>* amp = 0;
	57	EvtPdf<EvtDalitzPoint>* pdf = 0;
	58	std::string name;
	59	Pair pairRes=AB;
	60
	61	size_t i;
	62	/*
	63	Experimental amplitudes
	64	*/
65	if(vv[0] == "PHASESPACE") {
66
67	pdf = new EvtDalitzFlatPdf(_dp);
68	amp = new EvtFlatAmp<EvtDalitzPoint>();
69	name = "NR";
70	}
71	else if (!vv[0].find("NONRES")) {
72	double alpha=0;
73	EvtPto3PAmp::NumType typeNRes=EvtPto3PAmp::NONRES;
74	if (vv[0]=="NONRES_LIN") {
75	typeNRes=EvtPto3PAmp::NONRES_LIN;
76	pairRes=strToPair(vv[1].c_str());
77	}
78	else if (vv[0]=="NONRES_EXP") {
79	typeNRes=EvtPto3PAmp::NONRES_EXP;
80	pairRes = strToPair(vv[1].c_str());
81	alpha = strtod(vv[2].c_str(),0);
82	}
83	else assert(0);
84	pdf = new EvtDalitzFlatPdf(_dp);
85	amp = new EvtNonresonantAmp( &_dp, typeNRes, pairRes, alpha);
86	}
87	else if (vv[0]=="LASS") {
88	pairRes = strToPair(vv[1].c_str());
89	double m0 = strtod(vv[2].c_str(),0);
90	double g0 = strtod(vv[3].c_str(),0);
91	double a = strtod(vv[4].c_str(),0);
92	double r = strtod(vv[5].c_str(),0);
93	double cutoff = strtod(vv[6].c_str(),0);
94	pdf = new EvtDalitzResPdf(_dp,m0,g0,pairRes);
95	amp = new EvtLASSAmp( &_dp, pairRes, m0, g0, a, r, cutoff);
96	}
97
98	/*
99	Resonant amplitudes
100	*/
101	else if(vv[0] == "RESONANCE") {
102	EvtPto3PAmp* partAmp = 0;
103
104	// RESONANCE stanza
105
106	pairRes = strToPair(vv[1].c_str());
107	EvtSpinType::spintype spinR;
108	double mR, gR;
109	name = vv[2];
110	EvtId resId = EvtPDL::getId(vv[2]);
111	if(_verbose) printf("Particles %s form %sresonance %s\n",
112	vv[1].c_str(),vv[2].c_str(), conj ? "(conj) " : "");
113
114	// If no valid particle name is given, assume that
115	// it is the spin, the mass and the width of the particle.
116
117	if(resId.getId() == -1) {
118
119	switch(atoi(vv[2].c_str())) {
120
121	case 0: { spinR = EvtSpinType::SCALAR; break; }
122	case 1: { spinR = EvtSpinType::VECTOR; break; }
123	case 2: { spinR = EvtSpinType::TENSOR; break; }
124	case 3: { spinR = EvtSpinType::SPIN3; break; }
125	case 4: { spinR = EvtSpinType::SPIN4; break; }
126	default: { assert(0); break; }
127	}
128
129	mR = strtod(vv[3].c_str(),0);
130	gR = strtod(vv[4].c_str(),0);
131	i = 4;
132	}
133	else {
134
135	// For a valid particle get spin, mass and width
136
137	spinR = EvtPDL::getSpinType(resId);
138	mR = EvtPDL::getMeanMass(resId);
139	gR = EvtPDL::getWidth(resId);
140	i = 2;
141
142	// It's possible to specify mass and width of a particle
143	// explicitly
144
145	if(vv[3] != "ANGULAR") {
146
147	if(_verbose)
148	printf("Setting m(%s)=%s g(%s)=%s\n",
149	vv[2].c_str(),vv[3].c_str(),vv[2].c_str(),vv[4].c_str());
150
151	mR = strtod(vv[3].c_str(),0);
152	gR = strtod(vv[4].c_str(),0);
153	i = 4;
154	}
155	}
156
157	// ANGULAR stanza
158
159	if(vv[++i] != "ANGULAR") {
160
161	printf("%s instead of ANGULAR\n",vv[i].c_str());
162	exit(0);
163	}
164	Pair pairAng = strToPair(vv[++i].c_str());
165	if(_verbose) printf("Angle is measured between particles %s\n",vv[i].c_str());
166
167	// TYPE stanza
168
169	assert(vv[++i] == "TYPE");
170	std::string type = vv[++i];
171	if(_verbose) printf("Propagator type %s\n",vv[i].c_str());
172
173	if(type == "NBW") {
174
175	EvtPropBreitWigner prop(mR,gR);
176	partAmp = new EvtPto3PAmp(_dp,pairAng,pairRes,spinR,prop,EvtPto3PAmp::NBW);
177	}
178	else if(type == "RBW_ZEMACH") {
179
180	EvtPropBreitWignerRel prop(mR,gR);
181	partAmp = new EvtPto3PAmp(_dp,pairAng,pairRes,spinR,prop,EvtPto3PAmp::RBW_ZEMACH);
182	}
183	else if(type == "RBW_KUEHN") {
184
185	EvtPropBreitWignerRel prop(mR,gR);
186	partAmp = new EvtPto3PAmp(_dp,pairAng,pairRes,spinR,prop,EvtPto3PAmp::RBW_KUEHN);
187	}
188	else if(type == "RBW_CLEO") {
189
190	EvtPropBreitWignerRel prop(mR,gR);
191	partAmp = new EvtPto3PAmp(_dp,pairAng,pairRes,spinR,prop,EvtPto3PAmp::RBW_CLEO);
192	}
193	else if(type == "FLATTE") {
194
195	double m1a = _dp.m( first(pairRes) );
196	double m1b = _dp.m( second(pairRes) );
197	// 2nd channel
198	double g2 = strtod(vv[++i].c_str(),0);
199	double m2a = strtod(vv[++i].c_str(),0);
200	double m2b = strtod(vv[++i].c_str(),0);
201	EvtPropFlatte prop( mR, gR, m1a, m1b, g2, m2a, m2b );
202	partAmp = new EvtPto3PAmp(_dp,pairAng,pairRes,spinR,prop,EvtPto3PAmp::FLATTE);
203	}
204	else assert(0);
205
206	// Optional DVFF, BVFF stanzas
207
208	if(i < vv.size() - 1) {
209	if(vv[i+1] == "DVFF") {
210	i++;
211	if(vv[++i] == "BLATTWEISSKOPF") {
212
213	double R = strtod(vv[++i].c_str(),0);
214	partAmp->set_fd(R);
215	}
216	else assert(0);
217	}
218	}
219
220	if(i < vv.size() - 1) {
221	if(vv[i+1] == "BVFF") {
222	i++;
223	if(vv[++i] == "BLATTWEISSKOPF") {
224
225	if(_verbose) printf("BVFF=%s\n",vv[i].c_str());
226	double R = strtod(vv[++i].c_str(),0);
227	partAmp->set_fb(R);
228	}
229	else assert(0);
230	}
231	}
232
233	const int minwidths=5;
234	//Optional resonance minimum and maximum
235	if(i < vv.size() - 1) {
236	if(vv[i+1] == "CUTOFF") {
237	i++;
238	if(vv[i+1] == "MIN") {
239	i++;
240	double min = strtod(vv[++i].c_str(),0);
241	if(_verbose) std::cout<<"CUTOFF MIN = "<<min<<std::endl;
242	//ensure against cutting off too close to the resonance
243	assert( min<(mR-minwidths*gR) );
244	partAmp->setmin(min);
245	}
246	else if (vv[i+1] == "MAX") {
247	i++;
248	double max = strtod(vv[++i].c_str(),0);
249	if(_verbose) std::cout<<"CUTOFF MAX = "<<max<<std::endl;
250	//ensure against cutting off too close to the resonance
251	assert( max>(mR+minwidths*gR) );
252	partAmp->setmax(max);
253	}
254	else assert(0);
255	}
256	}
257
258	//2nd iteration in case min and max are both specified
259	if(i < vv.size() - 1) {
260	if(vv[i+1] == "CUTOFF") {
261	i++;
262	if(vv[i+1] == "MIN") {
263	i++;
264	double min = strtod(vv[++i].c_str(),0);
265	if(_verbose) std::cout<<"CUTOFF MIN = "<<min<<std::endl;
266	//ensure against cutting off too close to the resonance
267	assert( min<(mR-minwidths*gR) );
268	partAmp->setmin(min);
269	}
270	else if (vv[i+1] == "MAX") {
271	i++;
272	double max = strtod(vv[++i].c_str(),0);
273	if(_verbose) std::cout<<"CUTOFF MAX = "<<max<<std::endl;
274	//ensure against cutting off too close to the resonance
275	assert( max>(mR+minwidths*gR) );
276	partAmp->setmax(max);
277	}
278	else assert(0);
279	}
280	}
281
282
283	i++;
284
285	pdf = new EvtDalitzResPdf(_dp,mR,gR,pairRes);
286	amp = partAmp;
287	}
288
289	assert(amp);
290	assert(pdf);
291
292	if(!conj) {
293	_amp->addOwnedTerm(c,amp);
294	}
295	else {
296	_ampConj->addOwnedTerm(c,amp);
297	}
298
299	double scale = matchIsobarCoef(_amp, pdf, pairRes);
300	_pc->addOwnedTerm(abs2(c)*scale,pdf);
301
302	_names.push_back(name);
303	}
304
305	double EvtPto3PAmpFactory::matchIsobarCoef(EvtAmplitude<EvtDalitzPoint>* amp,
306	EvtPdf<EvtDalitzPoint>* pdf,
307	EvtCyclic3::Pair ipair) {
308
309	// account for differences in the definition of amplitudes by matching
310	// Integral( c'pdf ) = Integral( c\|A\|^2 )
311	// to improve generation efficiency ...
312
313	double Ipdf = pdf->compute_integral(10000).value();
314	double Iamp2 = 0;
315
316
317	EvtCyclic3::Pair jpair = EvtCyclic3::next(ipair);
318	EvtCyclic3::Pair kpair = EvtCyclic3::next(jpair);
319
320	// Trapezoidal integral
321	int N=10000;
322
323	double di = (_dp.qAbsMax(ipair) - _dp.qAbsMin(ipair))/((double) N);
324
325	double siMin = _dp.qAbsMin(ipair);
326
327	double s[3]; // playing with fire
328	for(int i=1; i<N; i++) {
329
330	s[ipair] = siMin + di*i;
331	s[jpair] = _dp.q(jpair, 0.9999, ipair, s[ipair]);
332	s[kpair] = _dp.bigM()*_dp.bigM() - s[ipair] - s[jpair]
333	+ _dp.mA()_dp.mA() + _dp.mB()_dp.mB() + _dp.mC()*_dp.mC();
334
335	EvtDalitzPoint point( _dp.mA(), _dp.mB(), _dp.mC(),
336	s[EvtCyclic3::AB], s[EvtCyclic3::BC], s[EvtCyclic3::CA]);
337
338	if (!point.isValid()) continue;
339
340	double p = point.p(other(ipair), ipair);
341	double q = point.p(first(ipair), ipair);
342
343	double itg = abs2( amp->evaluate(point) )di4qp;
344	Iamp2 += itg;
345
346	}
347	if (_verbose) std::cout << "integral = " << Iamp2 << " pdf="<<Ipdf << std::endl;
348
349	assert(Ipdf>0 && Iamp2>0);
350
351	return Iamp2/Ipdf;
352	}