db/d3f/EvtJ2BB2_8cc_source.html

//--------------------------------------------------------------------------

//

// Environment:

//      This software is part of models developed at BES collaboration

//      based on the EvtGen framework.  If you use all or part

//      of it, please give an appropriate acknowledgement.

//

// Copyright Information: See EvtGen/BesCopyright

//      Copyright (A) 2006      Ping Rong-Gang @IHEP

//

// Module: EvtJ2BB2.cc //

// Description: Routine to decay jpsi or psi(2S) to B10 B10 bar.

// The augular distribution parameter alpha is writed as -- in the model

// with  use the Carimalo approach that it is expended by us for jpsi or

// psi(2S) decays B10 B10 bar.

//

// Modification history:

//

//  Pang C.Y. and  Ping R.-G.       Apr, 2007       Module created

//

//------------------------------------------------------------------------


#include "EvtJ2BB2.hh"

#include "../EvtGenBase/EvtGenKine.hh"

#include "../EvtGenBase/EvtHelSys.hh"

#include "../EvtGenBase/EvtPDL.hh"

#include "../EvtGenBase/EvtParticle.hh"

#include "../EvtGenBase/EvtPatches.hh"

#include "../EvtGenBase/EvtRaritaSchwinger.hh"

#include "../EvtGenBase/EvtRaritaSchwingerParticle.hh"

#include "../EvtGenBase/EvtReport.hh"

#include "../EvtGenBase/EvtTensor4C.hh"

#include "../EvtGenBase/EvtVector4C.hh"

#include "../EvtGenBase/EvtVector4R.hh"

#include "../EvtGenBase/EvtdFunctionSingle.hh"

#include <stdlib.h>


#include <string>


using std::cout;

using std::endl;

EvtJ2BB2::~EvtJ2BB2() {}


void EvtJ2BB2::getName( std::string& model_name ) { model_name = "J2BB2"; }


EvtDecayBase* EvtJ2BB2::clone() { return new EvtJ2BB2; }


void EvtJ2BB2::init() {

  // checkNArg(1);

  checkNDaug( 2 );

  checkSpinParent( EvtSpinType::VECTOR );

  checkSpinDaughter( 0, EvtSpinType::RARITASCHWINGER );

  checkSpinDaughter( 1, EvtSpinType::RARITASCHWINGER );

}


/*

void EvtJ2BB2::initProbMax() {


  //Hard coded... should not be hard to calculate...

 setProbMax(100.0);

}

*/


void EvtJ2BB2::decay( EvtParticle* p ) {


  static EvtId DZP  = EvtPDL::getId( "Delta0" );

  static EvtId DZM  = EvtPDL::getId( "anti-Delta0" );

  static EvtId DPP  = EvtPDL::getId( "Delta+" );

  static EvtId DPM  = EvtPDL::getId( "anti-Delta-" );

  static EvtId DMP  = EvtPDL::getId( "Delta-" );

  static EvtId DMM  = EvtPDL::getId( "anti-Delta+" );

  static EvtId DPPP = EvtPDL::getId( "Delta++" );

  static EvtId DPPM = EvtPDL::getId( "anti-Delta--" );


  static EvtId SZP = EvtPDL::getId( "Sigma*0" );

  static EvtId SZM = EvtPDL::getId( "anti-Sigma*0" );

  static EvtId SPP = EvtPDL::getId( "Sigma*+" );

  static EvtId SPM = EvtPDL::getId( "anti-Sigma*-" );

  static EvtId SMP = EvtPDL::getId( "Sigma*-" );

  static EvtId SMM = EvtPDL::getId( "anti-Sigma*+" );


  static EvtId XP  = EvtPDL::getId( "Xi*-" );

  static EvtId XM  = EvtPDL::getId( "anti-Xi*+" );

  static EvtId XZP = EvtPDL::getId( "Xi*0" );

  static EvtId XZM = EvtPDL::getId( "anti-Xi*0" );


  static EvtId OP = EvtPDL::getId( "Omega-" );

  static EvtId OM = EvtPDL::getId( "anti-Omega+" );


  p->initializePhaseSpace( getNDaug(), getDaugs() );


  EvtParticle *v, *s1;

  EvtVector4R  pv, ps, ppr;


  v   = p->getDaug( 0 );

  s1  = p->getDaug( 1 );

  pv  = v->getP4();

  ps  = s1->getP4();

  ppr = p->getP4();

  //  Put phase space results into the daughters.

  EvtHelSys angles( ppr, pv ); // using helicity sys. angles

  double    theta = angles.getHelAng( 1 );

  double    phi   = angles.getHelAng( 2 );

  double    gamma = 0;

  /*  double costheta=cos(theta);

    double sintheta=sqrt(1-costheta*costheta);

    double d11=(1+costheta)/2.;

    double d1m1=(1-costheta)/2.;

    double d10=-sintheta/sqrt(2.);

    double dm10=-d10;

    double dm11=d1m1,dm1m1=d11;

    double d0m1=d10,d01=-d10,d00=costheta;

  */

  //  double mass_b1 = EvtPDL::getMass(getDaug(0));

  //  double mass_b2 = EvtPDL::getMass(getDaug(1));

  double mass_b1, mass_b2;

  EvtId  d1;

  d1 = v->getId();


  // the mass of daughters are defined in our model. Because the distribution of Delta

  // BreitWigner mass is very large.


  if ( ( d1 == XP ) || ( d1 == XM ) || ( d1 == XZP ) || ( d1 == XZM ) ) { mass_b1 = 1.532; }

  else if ( ( d1 == SPP ) || ( d1 == SPM ) || ( d1 == SMP ) || ( d1 == SMM ) ||

            ( d1 == SZP ) || ( d1 == SZM ) )

  { mass_b1 = 1.383; }

  else if ( ( d1 == DZP ) || ( d1 == DZM ) || ( d1 == DPP ) || ( d1 == DPM ) ||

            ( d1 == DMP ) || ( d1 == DMM ) || ( d1 == DPPP ) || ( d1 == DPPM ) )

  { mass_b1 = 1.232; }

  else if ( ( d1 == OP ) || d1 == OM ) { mass_b1 = 1.67245; }

  else

  { cout << "The decay is not the process: J/psi->B10 B10bar(decuplet baryon) ." << endl; }


  mass_b2       = mass_b1;

  double mass_M = EvtPDL::getMass( getParentId() );


  //  double c1=pow(pv.d3mag(),2.0);

  //  double R=(mass_b1+pv.get(0))*(mass_b2+ps.get(0));


  double R  = pow( mass_b1 + mass_M / 2.0, 2.0 );

  double c1 = mass_M * mass_M / 4.0 - mass_b1 * mass_b1;

  double u  = pow( ( R - c1 ) / ( R + c1 ), 2.0 );


  if ( getNArg() > 0 ) { alpha = getArg( 0 ); }

  else

  { alpha = ( -9 * u * u * u + 17 * u * u - 16 * u + 8 ) / ( 9 * u * u * u - 7 * u * u + 8 ); }


  double F00, F01, F03, F10, F11, F22, F23, F30, F32, F33;

  double scale1 = sqrt( 3.0 ) * u / ( u - 2.0 ); // scale1=F01:F03.

  double scale2 = 3.0 * u / ( 3.0 * u - 4 );     // scale2=F11:F00.


  //  F00=1.0; F01=scale1*F03;F11=scale2*F00;

  //  F03=sqrt(2.0*(1.0+scale2*scale2)*(1.0+alpha)/((1.0-alpha)*(1.0+2.0*scale1*scale1)));


  F00 = sqrt( ( 1 - alpha ) / ( 4.0 * ( 1.0 + scale2 * scale2 ) ) );

  F03 = sqrt( ( 1 + alpha ) / ( 2.0 * ( 1.0 + 2.0 * scale1 * scale1 ) ) );

  F01 = scale1 * F03;

  F11 = scale2 * F00;

  F22 = F11;

  F32 = F01;

  F33 = F00;

  F30 = F03;

  F10 = F01;

  F23 = F32; // 07.2


  // J/psi helicity =1,-1,0 corresponding index=0,1,2

  // decuplt baryon helicity =1/2,3/2,-3/2,-1/2 corresponding index=0,1,2,3

  vertex( 0, 0, 0, Djmn( 1, 1, 0, phi, theta, gamma ) * F00 );

  vertex( 0, 0, 1, Djmn( 1, 1, -1, phi, theta, gamma ) * F01 );

  vertex( 0, 0, 2, 0.0 );

  vertex( 0, 0, 3, Djmn( 1, 1, 1, phi, theta, gamma ) * F03 );

  vertex( 0, 1, 0, Djmn( 1, 1, 1, phi, theta, gamma ) * F10 );

  vertex( 0, 1, 1, Djmn( 1, 1, 0, phi, theta, gamma ) * F11 );

  vertex( 0, 1, 2, 0.0 );

  vertex( 0, 1, 3, 0.0 );

  vertex( 0, 2, 0, 0.0 );

  vertex( 0, 2, 1, 0.0 );

  vertex( 0, 2, 2, Djmn( 1, 1, 0, phi, theta, gamma ) * F22 );

  vertex( 0, 2, 3, Djmn( 1, 1, -1, phi, theta, gamma ) * F23 );

  vertex( 0, 3, 0, Djmn( 1, 1, -1, phi, theta, gamma ) * F30 );

  vertex( 0, 3, 1, 0.0 );

  vertex( 0, 3, 2, Djmn( 1, 1, 1, phi, theta, gamma ) * F32 );

  vertex( 0, 3, 3, Djmn( 1, 1, 0, phi, theta, gamma ) * F33 );


  vertex( 1, 0, 0, Djmn( 1, -1, 0, phi, theta, gamma ) * F00 );

  vertex( 1, 0, 1, Djmn( 1, -1, -1, phi, theta, gamma ) * F01 );

  vertex( 1, 0, 2, 0.0 );

  vertex( 1, 0, 3, Djmn( 1, -1, 1, phi, theta, gamma ) * F03 );

  vertex( 1, 1, 0, Djmn( 1, -1, 1, phi, theta, gamma ) * F10 );

  vertex( 1, 1, 1, Djmn( 1, -1, 0, phi, theta, gamma ) * F11 );

  vertex( 1, 1, 2, 0.0 );

  vertex( 1, 1, 3, 0.0 );

  vertex( 1, 2, 0, 0.0 );

  vertex( 1, 2, 1, 0.0 );

  vertex( 1, 2, 2, Djmn( 1, -1, 0, phi, theta, gamma ) * F22 );

  vertex( 1, 2, 3, Djmn( 1, -1, -1, phi, theta, gamma ) * F23 );

  vertex( 1, 3, 0, Djmn( 1, -1, -1, phi, theta, gamma ) * F30 );

  vertex( 1, 3, 1, 0.0 );

  vertex( 1, 3, 2, Djmn( 1, -1, 1, phi, theta, gamma ) * F32 );

  vertex( 1, 3, 3, Djmn( 1, -1, 0, phi, theta, gamma ) * F33 );


  vertex( 2, 0, 0, Djmn( 1, 0, 0, phi, theta, gamma ) * F00 );

  vertex( 2, 0, 1, Djmn( 1, 0, -1, phi, theta, gamma ) * F01 );

  vertex( 2, 0, 2, 0.0 );

  vertex( 2, 0, 3, Djmn( 1, 0, 1, phi, theta, gamma ) * F03 );

  vertex( 2, 1, 0, Djmn( 1, 0, 1, phi, theta, gamma ) * F10 );

  vertex( 2, 1, 1, Djmn( 1, 0, 0, phi, theta, gamma ) * F11 );

  vertex( 2, 1, 2, 0.0 );

  vertex( 2, 1, 3, 0.0 );

  vertex( 2, 2, 0, 0.0 );

  vertex( 2, 2, 1, 0.0 );

  vertex( 2, 2, 2, Djmn( 1, 0, 0, phi, theta, gamma ) * F22 );

  vertex( 2, 2, 3, Djmn( 1, 0, -1, phi, theta, gamma ) * F23 );

  vertex( 2, 3, 0, Djmn( 1, 0, -1, phi, theta, gamma ) * F30 );

  vertex( 2, 3, 1, 0.0 );

  vertex( 2, 3, 2, Djmn( 1, 0, 1, phi, theta, gamma ) * F32 );

  vertex( 2, 3, 3, Djmn( 1, 0, 0, phi, theta, gamma ) * F33 );


  return;

}


EvtGenKine.hh

Djmn
EvtComplex Djmn(int j, int m, int n, double phi, double theta, double gamma)
Definition EvtHelSys.cc:165

EvtHelSys.hh

EvtJ2BB2.hh

EvtPDL.hh

EvtParticle.hh

EvtPatches.hh

EvtRaritaSchwingerParticle.hh

EvtRaritaSchwinger.hh

EvtReport.hh

EvtTensor4C.hh

EvtVector4C.hh

EvtVector4R.hh

EvtdFunctionSingle.hh

v
**********Class see also m_nmax DOUBLE PRECISION m_amel DOUBLE PRECISION m_x2 DOUBLE PRECISION m_alfinv DOUBLE PRECISION m_Xenph INTEGER m_KeyWtm INTEGER m_idyfs DOUBLE PRECISION m_zini DOUBLE PRECISION m_q2 DOUBLE PRECISION m_Wt_KF DOUBLE PRECISION m_WtCut INTEGER m_KFfin *COMMON c_KarLud $ !Input CMS energy[GeV] $ !CMS energy after beam spread beam strahlung[GeV] $ !Beam energy spread[GeV] $ !z boost due to beam spread $ !electron beam mass *ff pair spectrum $ !minimum v
Definition KarLud.h:35

EvtDecayAmp::vertex
void vertex(const EvtComplex &amp)
Definition EvtDecayAmp.hh:36

EvtDecayBase::checkSpinDaughter
void checkSpinDaughter(int d1, EvtSpinType::spintype sp)
Definition EvtDecayBase.cc:492

EvtDecayBase::checkSpinParent
void checkSpinParent(EvtSpinType::spintype sp)
Definition EvtDecayBase.cc:479

EvtDecayBase::getArg
double getArg(int j)
Definition EvtDecayBase.cc:520

EvtDecayBase::EvtDecayBase
EvtDecayBase()
Definition EvtDecayBase.cc:205

EvtDecayBase::getParentId
EvtId getParentId()
Definition EvtDecayBase.hh:63

EvtDecayBase::getNDaug
int getNDaug()
Definition EvtDecayBase.hh:67

EvtDecayBase::getNArg
int getNArg()
Definition EvtDecayBase.hh:70

EvtDecayBase::checkNDaug
void checkNDaug(int d1, int d2=-1)
Definition EvtDecayBase.cc:465

EvtDecayBase::getDaugs
EvtId * getDaugs()
Definition EvtDecayBase.hh:68

EvtHelSys
Definition EvtHelSys.hh:44

EvtHelSys::getHelAng
double getHelAng(int i)
Definition EvtHelSys.cc:52

EvtId
Definition EvtId.hh:27

EvtJ2BB2::EvtJ2BB2
EvtJ2BB2()
Definition EvtJ2BB2.hh:31

EvtJ2BB2::alpha
double alpha
Definition EvtJ2BB2.hh:42

EvtJ2BB2::u
double u
Definition EvtJ2BB2.hh:43

EvtJ2BB2::clone
EvtDecayBase * clone()
Definition EvtJ2BB2.cc:46

EvtJ2BB2::init
void init()
Definition EvtJ2BB2.cc:48

EvtJ2BB2::decay
void decay(EvtParticle *p)
Definition EvtJ2BB2.cc:64

EvtJ2BB2::getName
void getName(std::string &name)
Definition EvtJ2BB2.cc:44

EvtJ2BB2::~EvtJ2BB2
virtual ~EvtJ2BB2()
Definition EvtJ2BB2.cc:42

EvtPDL::getMass
static double getMass(EvtId i)
Definition EvtPDL.hh:44

EvtPDL::getId
static EvtId getId(const std::string &name)
Definition EvtPDL.cc:272

EvtParticle
Definition EvtParticle.hh:42

EvtParticle::getP4
const EvtVector4R & getP4() const
Definition EvtParticle.cc:108

EvtParticle::getDaug
EvtParticle * getDaug(int i)
Definition EvtParticle.cc:80

EvtParticle::initializePhaseSpace
double initializePhaseSpace(int numdaughter, EvtId *daughters, double poleSize=-1., int whichTwo1=0, int whichTwo2=1)
Definition EvtParticle.cc:1042

EvtSpinType::RARITASCHWINGER
@ RARITASCHWINGER
Definition EvtSpinType.hh:38

EvtSpinType::VECTOR
@ VECTOR
Definition EvtSpinType.hh:32

EvtVector4R
Definition EvtVector4R.hh:29