EvtSVVCP.cc

Go to the documentation of this file.

//--------------------------------------------------------------------------
//
// 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: See EvtGen/COPYRIGHT
//      Copyright (C) 1998      Caltech, UCSB
//
// Module: EvtSVVCP.cc
//
// Description: The decay of a scalar to two vector particles are 
//              performed with CP violation. E.g. B->J/psi K*.
//
// Modification history:
//
//    RYD       January 19, 1997       Module created
//
//------------------------------------------------------------------------
//
#include "EvtGenBase/EvtPatches.hh"
#include <stdlib.h>
#include "EvtGenBase/EvtParticle.hh"
#include "EvtGenBase/EvtGenKine.hh"
#include "EvtGenBase/EvtCPUtil.hh"
#include "EvtGenBase/EvtPDL.hh"
#include "EvtGenModels/EvtSVVHelAmp.hh"
#include "EvtGenBase/EvtReport.hh"
#include "EvtGenModels/EvtSVVCP.hh"
#include "EvtGenBase/EvtId.hh"
#include <string>
#include "EvtGenBase/EvtConst.hh"
 
EvtSVVCP::~EvtSVVCP() {}
 
void EvtSVVCP::getName(std::string& model_name){
 
  model_name="SVV_CP";     
 
}
 
 
EvtDecayBase* EvtSVVCP::clone(){
 
  return new EvtSVVCP;
 
}
 
void EvtSVVCP::init(){
 
  // check that there are 9 arguments
  checkNArg(9);
  checkNDaug(2);
 
  checkSpinParent(EvtSpinType::SCALAR);
 
  checkSpinDaughter(0,EvtSpinType::VECTOR);
  checkSpinDaughter(1,EvtSpinType::VECTOR);
 
}
 
void EvtSVVCP::initProbMax(){
 
  //This is probably not quite right, but it should do as a start...
  //Anders
 
  setProbMax(2*(getArg(3)*getArg(3)+getArg(5)*getArg(5)+getArg(7)*getArg(7)));
 
}
 
void EvtSVVCP::decay( EvtParticle *p){
 
  //added by Lange Jan4,2000
  static EvtId B0=EvtPDL::getId("B0");
  static EvtId B0B=EvtPDL::getId("anti-B0");
 
  double t;
  EvtId other_b;
 
  EvtCPUtil::OtherB(p,t,other_b);
 
   EvtComplex G0P,G1P,G1M;
 
   G1P=EvtComplex(getArg(3)*cos(getArg(4)),getArg(3)*sin(getArg(4)));
   G0P=EvtComplex(getArg(5)*cos(getArg(6)),getArg(5)*sin(getArg(6)));
   G1M=EvtComplex(getArg(7)*cos(getArg(8)),getArg(7)*sin(getArg(8)));
 
   EvtComplex lambda_km=EvtComplex(cos(-2*getArg(0)),sin(-2*getArg(0)));
 
   double cdmt=cos(getArg(1)*t/(2*EvtConst::c));
   double sdmt=sin(getArg(1)*t/(2*EvtConst::c));
 
   EvtComplex cG0P,cG1P,cG1M;
 
   if (other_b==B0B){
     cG0P=G0P*(cdmt+lambda_km*EvtComplex(0.0,getArg(2)*sdmt));
     cG1P=G1P*(cdmt+lambda_km*EvtComplex(0.0,getArg(2)*sdmt));
     cG1M=G1M*(cdmt-lambda_km*EvtComplex(0.0,getArg(2)*sdmt));
   }
   if (other_b==B0){
     cG0P=G0P*(cdmt+(1.0/lambda_km)*EvtComplex(0.0,getArg(2)*sdmt));
     cG1P=G1P*(cdmt+(1.0/lambda_km)*EvtComplex(0.0,getArg(2)*sdmt));
     cG1M=-G1M*(cdmt-(1.0/lambda_km)*EvtComplex(0.0,getArg(2)*sdmt));
 
   }
 
   EvtComplex A0,AP,AM;
 
   A0=cG0P/sqrt(2.0);
   AP=(cG1P+cG1M)/sqrt(2.0); 
   AM=(cG1P-cG1M)/sqrt(2.0); 
 
   EvtSVVHelAmp::SVVHel(p,_amp2,getDaug(0),getDaug(1),AP,A0,AM);
 
  return ;
}