EvtJ2BB1 Class Reference

#include <EvtJ2BB1.hh>

Inheritance diagram for EvtJ2BB1:

Public Member Functions
	EvtJ2BB1 ()
virtual	~EvtJ2BB1 ()
void	getName (std::string &name)
EvtDecayBase *	clone ()
void	decay (EvtParticle *p)
void	init ()
void	init (int, double *)
Public Member Functions inherited from EvtDecayAmp
void	makeDecay (EvtParticle *p)
void	setWeight (double weight)
void	vertex (const EvtComplex &amp)
void	vertex (int i1, const EvtComplex &amp)
void	vertex (int i1, int i2, const EvtComplex &amp)
void	vertex (int i1, int i2, int i3, const EvtComplex &amp)
void	vertex (int *i1, const EvtComplex &amp)
virtual	~EvtDecayAmp ()
Public Member Functions inherited from EvtDecayBase
virtual void	initProbMax ()
virtual std::string	commandName ()
virtual void	command (std::string cmd)
double	getProbMax (double prob)
double	resetProbMax (double prob)
	EvtDecayBase ()
virtual	~EvtDecayBase ()
virtual bool	matchingDecay (const EvtDecayBase &other) const
EvtId	getParentId ()
double	getBranchingFraction ()
void	disableCheckQ ()
void	checkQ ()
int	getNDaug ()
EvtId *	getDaugs ()
EvtId	getDaug (int i)
int	getNArg ()
int	getPHOTOS ()
void	setPHOTOS ()
void	setVerbose ()
void	setSummary ()
double *	getArgs ()
std::string *	getArgsStr ()
double	getArg (int j)
std::string	getArgStr (int j)
std::string	getModelName ()
int	getDSum ()
int	summary ()
int	verbose ()
void	saveDecayInfo (EvtId ipar, int ndaug, EvtId *daug, int narg, std::vector< std::string > &args, std::string name, double brfr)
void	printSummary ()
void	setProbMax (double prbmx)
void	noProbMax ()
void	checkNArg (int a1, int a2=-1, int a3=-1, int a4=-1)
void	checkNDaug (int d1, int d2=-1)
void	checkSpinParent (EvtSpinType::spintype sp)
void	checkSpinDaughter (int d1, EvtSpinType::spintype sp)
virtual int	nRealDaughters ()

Public Attributes
double	alpha
double	u

Additional Inherited Members
Static Public Member Functions inherited from EvtDecayBase
static void	findMasses (EvtParticle *p, int ndaugs, EvtId daugs[10], double masses[10])
static void	findMass (EvtParticle *p)
static double	findMaxMass (EvtParticle *p)
Protected Member Functions inherited from EvtDecayBase
bool	daugsDecayedByParentModel ()
Protected Attributes inherited from EvtDecayAmp
EvtAmp	_amp2
Protected Attributes inherited from EvtDecayBase
bool	_daugsDecayedByParentModel

Detailed Description

Definition at line 28 of file EvtJ2BB1.hh.

Constructor & Destructor Documentation

EvtJ2BB1()

EvtJ2BB1::EvtJ2BB1 ( )

inline

Definition at line 31 of file EvtJ2BB1.hh.

{}

Referenced by clone().

~EvtJ2BB1()

EvtJ2BB1::~EvtJ2BB1 ( )

virtual

Definition at line 36 of file EvtJ2BB1.cc.

{}

Member Function Documentation

clone()

EvtDecayBase * EvtJ2BB1::clone ( )

virtual

Implements EvtDecayBase.

Definition at line 40 of file EvtJ2BB1.cc.

{ return new EvtJ2BB1; }

decay()

void EvtJ2BB1::decay ( EvtParticle * p )

virtual

Implements EvtDecayBase.

Definition at line 56 of file EvtJ2BB1.cc.

                                     {
 
  p->initializePhaseSpace( getNDaug(), getDaugs() );
 
  EvtParticle *v, *s1;
  EvtVector4R  pv, ps, ppr;
 
  v   = p->getDaug( 0 ); // Baryon
  s1  = p->getDaug( 1 ); // Baryon
  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 ); // using helicity angles in parent system
  //  double costheta=ppr.get(3)/ppr.d3mag();  //using Lab system
 
  if ( getNArg() > 0 ) { alpha = getArg( 0 ); }
  else
  {
    double mass_b1 = EvtPDL::getMass( getDaug( 0 ) );
    double mass_b2 = EvtPDL::getMass( getDaug( 1 ) );
    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 ) );
    u              = pow( ( R - c1 ) / ( R + c1 ), 2.0 );
    alpha          = ( pow( 4 + u, 2.0 ) - u * pow( 2 + 3 * u, 2.0 ) ) /
            ( pow( 4 + u, 2.0 ) + u * pow( 2 + 3 * u, 2.0 ) );
  }
 
  double F01 = sqrt( ( 1 + alpha ) / 2 );
  double F00 = sqrt( ( 1 - alpha ) / 4 );
  double F10 = F01;
  double F11 = F00;
 
  vertex( 0, 0, 0, Djmn( 1, 1, 0, phi, theta, gamma ) * F00 ); // J/psi helicity =1
                                                               // corresponding index=0
  vertex( 0, 0, 1, Djmn( 1, 1, 1, phi, theta, gamma ) * F01 );
  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( 1, 0, 0, Djmn( 1, -1, 0, phi, theta, gamma ) * F00 ); // J/psi helicity =-1
                                                                // corresponding index=1
  vertex( 1, 0, 1, Djmn( 1, -1, 1, phi, theta, gamma ) * F01 );
  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( 2, 0, 0, Djmn( 1, 0, 0, phi, theta, gamma ) * F00 ); // J/psi helicity =0
                                                               // corresponding index=2
  vertex( 2, 0, 1, Djmn( 1, 0, 1, phi, theta, gamma ) * F01 );
  vertex( 2, 1, 0, Djmn( 1, 0, -1, phi, theta, gamma ) * F10 );
  vertex( 2, 1, 1, Djmn( 1, 0, 0, phi, theta, gamma ) * F11 );
 
  return;
}

getName()

void EvtJ2BB1::getName ( std::string & name )

virtual

Implements EvtDecayBase.

Definition at line 38 of file EvtJ2BB1.cc.

{ model_name = "J2BB1"; }

init() [1/2]

void EvtJ2BB1::init ( )

virtual

Reimplemented from EvtDecayBase.

Definition at line 49 of file EvtJ2BB1.cc.

                    {
  checkNDaug( 2 );
  checkSpinParent( EvtSpinType::VECTOR );
  checkSpinDaughter( 0, EvtSpinType::DIRAC );
  checkSpinDaughter( 1, EvtSpinType::DIRAC );
}

init() [2/2]

void EvtJ2BB1::init	(	int	,
		double *	)

Member Data Documentation

alpha

double EvtJ2BB1::alpha

Definition at line 42 of file EvtJ2BB1.hh.

Referenced by decay().

u

double EvtJ2BB1::u

Definition at line 43 of file EvtJ2BB1.hh.

Referenced by decay().

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The documentation for this class was generated from the following files:

• EvtJ2BB1.hh
• EvtJ2BB1.cc