Belle2::EvtEtaFullDalitz Class Reference

Class for the simulation of the eta -> pi+pi-pi0 decay with an improved dalitz description. More...

#include <EvtEtaFullDalitz.h>

Inheritance diagram for Belle2::EvtEtaFullDalitz:

Collaboration diagram for Belle2::EvtEtaFullDalitz:

Public Member Functions
	EvtEtaFullDalitz ()
	Default Constructor. More...
virtual	~EvtEtaFullDalitz ()
	Default Destructor. More...
std::string	getName ()
	Returns the model name: ETA_FULLDALITZ. More...
EvtDecayBase *	clone ()
	Makes a copy of the pointer to the class. More...
void	init ()
	Checks that the number of input parameters are correct: More...
void	initProbMax ()
	Sets the Maximum probability for the PHSP reweight. More...
void	decay (EvtParticle *p)
	Function that implements the energy-dependent Dalitz. More...

Detailed Description

Class for the simulation of the eta -> pi+pi-pi0 decay with an improved dalitz description.

Evolution of the former EvtEtaDalitz, that implements a simpler Dalitz description with hard-coded parameters. The general structure of the class, as well as several methods, are inherited from it.

The chosen pametrization is based on a power expansion of the decay amplitude squared with real cefficients (see PDG 2015):

|M|^2 = 1 + a*Y + b*Y^2 + c*X + d*X^2 + e*X*Y + f*Y^3,

where the kinematic variable X and Y are both linear combinations of the pions' kinetic energies in the eta frame.

The model takes 6 parameters corresponing to the six coeafficients a,b,c,d,e,f; c!=0 or e=0 are indication of CP violation in eta decay, and are therefore usually set to 0. An implementation of the model with the parameters report in Phys.Rev. D92 (2015) 012014 is:

ETA_FULLDALITZ -1.128 0.153 0.0 0.085 0.0 0.173;

In principle the class could be used also to model eta' -> pi+pi-pi0

Definition at line 46 of file EvtEtaFullDalitz.h.

Constructor & Destructor Documentation

EvtEtaFullDalitz()

Belle2::EvtEtaFullDalitz::EvtEtaFullDalitz ( )

inline

Default Constructor.

Definition at line 51 of file EvtEtaFullDalitz.h.

{}

~EvtEtaFullDalitz()

virtual Belle2::EvtEtaFullDalitz::~EvtEtaFullDalitz ( )

virtual

Default Destructor.

Member Function Documentation

clone()

EvtDecayBase* Belle2::EvtEtaFullDalitz::clone

(

)

Makes a copy of the pointer to the class.

decay()

void Belle2::EvtEtaFullDalitz::decay

(

EvtParticle *

p

)

Function that implements the energy-dependent Dalitz.

getName()

std::string Belle2::EvtEtaFullDalitz::getName

(

)

Returns the model name: ETA_FULLDALITZ.

init()

void Belle2::EvtEtaFullDalitz::init

(

)

Checks that the number of input parameters are correct:

• 3 scalar particles (check on spin but not on charge)
• 6 real parameters (no check on the actual values)

initProbMax()

void Belle2::EvtEtaFullDalitz::initProbMax

(

)

Sets the Maximum probability for the PHSP reweight.

Maximum value is hardcoded and inherited from the EvtEtaDalitz class.

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

• EvtEtaFullDalitz.h