BOSS_7.0.2: /home/bes3soft/bes3soft/Boss/7.0.2/dist/7.0.2/Generator/BesEvtGen/BesEvtGen-00-03-58/src/EvtGen/EvtGenModels/EvtSSSCP.cc Source File

00001 //--------------------------------------------------------------------------
00002 //
00003 // Environment:
00004 //      This software is part of the EvtGen package developed jointly
00005 //      for the BaBar and CLEO collaborations.  If you use all or part
00006 //      of it, please give an appropriate acknowledgement.
00007 //
00008 // Copyright Information: See EvtGen/COPYRIGHT
00009 //      Copyright (C) 1998      Caltech, UCSB
00010 //
00011 // Module: EvtSSSCP.cc
00012 //
00013 // Description: Routine to decay scalar -> 2 scalars
00014 //
00015 // Modification history:
00016 //
00017 //    RYD       November 24, 1996       Module created
00018 //
00019 //------------------------------------------------------------------------
00020 // 
00021 #include "EvtGenBase/EvtPatches.hh"
00022 #include <stdlib.h>
00023 #include "EvtGenBase/EvtParticle.hh"
00024 #include "EvtGenBase/EvtGenKine.hh"
00025 #include "EvtGenBase/EvtCPUtil.hh"
00026 #include "EvtGenBase/EvtPDL.hh"
00027 #include "EvtGenBase/EvtReport.hh"
00028 #include "EvtGenModels/EvtSSSCP.hh"
00029 #include <string>
00030 #include "EvtGenBase/EvtConst.hh"
00031 
00032 EvtSSSCP::~EvtSSSCP() {}
00033 
00034 void EvtSSSCP::getName(std::string& model_name){
00035 
00036   model_name="SSS_CP";     
00037 
00038 }
00039 
00040 
00041 EvtDecayBase* EvtSSSCP::clone(){
00042 
00043   return new EvtSSSCP;
00044 
00045 }
00046 
00047 void EvtSSSCP::init(){
00048 
00049   // check that there are 7 arguments
00050   checkNArg(7);
00051   checkNDaug(2);
00052   checkSpinParent(EvtSpinType::SCALAR);
00053 
00054   checkSpinDaughter(0,EvtSpinType::SCALAR);
00055   checkSpinDaughter(1,EvtSpinType::SCALAR);
00056 
00057 }
00058 
00059 void EvtSSSCP::initProbMax(){
00060 
00061   //This is probably not quite right, but it should do as a start...
00062   //Anders
00063 
00064   setProbMax(2*(getArg(3)*getArg(3)+getArg(5)*getArg(5)));
00065 
00066 }
00067 
00068 void EvtSSSCP::decay( EvtParticle *p ){
00069 
00070   //added by Lange Jan4,2000
00071   static EvtId B0=EvtPDL::getId("B0");
00072   static EvtId B0B=EvtPDL::getId("anti-B0");
00073 
00074   double t;
00075   EvtId other_b;
00076 
00077   EvtCPUtil::OtherB(p,t,other_b);
00078 
00079   p->initializePhaseSpace(getNDaug(),getDaugs());
00080 
00081 
00082   EvtComplex amp;
00083 
00084   EvtComplex A,Abar;
00085   
00086   A=EvtComplex(getArg(3)*cos(getArg(4)),getArg(3)*sin(getArg(4)));
00087   Abar=EvtComplex(getArg(5)*cos(getArg(6)),getArg(5)*sin(getArg(6)));
00088    
00089   if (other_b==B0B){
00090     amp=A*cos(getArg(1)*t/(2*EvtConst::c))+
00091       EvtComplex(cos(-2.0*getArg(0)),sin(-2.0*getArg(0)))*
00092       getArg(2)*EvtComplex(0.0,1.0)*Abar*sin(getArg(1)*t/(2*EvtConst::c));
00093   }
00094   if (other_b==B0){
00095     amp=A*EvtComplex(cos(2.0*getArg(0)),sin(2.0*getArg(0)))*
00096       EvtComplex(0.0,1.0)*sin(getArg(1)*t/(2*EvtConst::c))+       
00097       getArg(2)*Abar*cos(getArg(1)*t/(2*EvtConst::c));
00098   }
00099   
00100   vertex(amp);
00101   
00102   return ;
00103 }
00104