The MixedParticleData class is designed to store the particle data for particles which undergo mixing with their anti-particle, e.g. More...

#include <MixedParticleData.h>

Inheritance diagram for ThePEG::MixedParticleData:

[legend]

Public Member Functions
	MixedParticleData ()
	The default constructor.

Public Member Functions inherited from ThePEG::ParticleData
	ParticleData ()
	Default constructor.

long	id () const
	Return the PDG id number.

const string &	PDGName () const
	Return the generic PDG name.

const string &	genericName () const
	Return the generic PDG name.

PPtr	produceParticle (const Lorentz5Momentum &) const
	Produce a particle specifying momentum.

PPtr	produceParticle (const LorentzMomentum &) const
	Produce a particle specifying momentum.

PPtr	produceParticle (const LorentzMomentum &, Energy m) const
	Produce a particle specifying 4-momentum and a mass.

PPtr	produceParticle (const Momentum3 &pp=Momentum3()) const
	Produce a particle specifying 3-momentum.

PPtr	produceParticle (Energy m, const Momentum3 &pp=Momentum3()) const
	Produce a particle specifying mass and 3-momentum.

PPtr	produceParticle (Energy plus, Energy minus, Energy px, Energy py) const
	Produce a particle specifying light-cone momentum components and transverse momentum components.

Energy	generateMass () const
	Generate a mass for an instance of this particle type.

Energy	generateWidth (Energy mass) const
	Generate a width for an instance of this particle type.

Length	generateLifeTime (Energy mass, Energy width) const
	Generate a mass for an instance of this particle type.

const DecaySelector &	decaySelector () const
	Return the nominal decay selector for this particle.

tDMPtr	selectMode (Particle &p) const
	Selects a decay mode randomly according to the branching ratios.

const DecaySet &	decayModes () const
	Access all the decay modes, including those which are switched off, or have zero branching ratio.

Energy	mass (Energy)
	Set the nominal mass.

Energy	mass () const
	Return the nominal mass.

Energy	hardProcessMass () const
	Return the mass to be used when evaluating hard process cross sections.

Energy	massMax () const
	Return the maximum possible mass of this particle type.

Energy	massMin () const
	Return the minimum possible mass of this particle type.

virtual Energy	constituentMass () const
	Return the constituent mass of this particle if relevant.

Energy	width (Energy)
	Set the width.

Energy	width () const
	Get the width.

Energy	widthCut (Energy wci)
	Set the width cut.

Energy	widthCut () const
	Get the width cut.

Energy	widthUpCut (Energy)
	Set the upper width cut.

Energy	widthUpCut () const
	Get the upper width cut.

Energy	widthLoCut (Energy)
	Set the lower width cut.

Energy	widthLoCut () const
	Get the lower width cut.

Length	cTau (Length)
	Set the life time cTau.

Length	cTau () const
	Get the life time cTau cTau.

Energy	hardProcessWidth () const
	Return the width to be used when evaluating hard process cross sections.

PDT::Charge	iCharge (PDT::Charge)
	Set the charge.

Charge	charge () const
	Get the charge.

PDT::Charge	iCharge () const
	Get the charge.

bool	charged () const
	Return true if charged.

bool	positive () const
	Return true if positively charged.

bool	negative () const
	Return true if negatively charged.

PDT::Spin	iSpin (PDT::Spin)
	Set the spin.

AngularMomentum	spin () const
	Get the spin.The spin is returned in standard units.

PDT::Spin	iSpin () const
	Get the spin.

PDT::Colour	iColour (PDT::Colour)
	Set the colour of the particle in units of PDT::Colour.

PDT::Colour	iColour () const
	Get the colour of the particle in units of PDT::Colour.

bool	coloured () const
	Return true if coloured.

bool	hasColour (bool anti=false) const
	Return true if (anti) coloured or colour-octet.

bool	hasAntiColour () const
	Return true if anti coloured or colour-octet.

PDT::ColouredInteraction	colouredInteraction () const
	Return what kind of colour charge this particle carries.

void	stable (bool stab)
	Specify if particle is to be considered stable according to stab.

bool	stable () const
	Return true if particle is to be considered stable.

tPDPtr	CC () const
	Get the pointer to the corresponding anti partner.

void	synchronized (bool sync)
	Specify if the anti partner chould be changed automatically when this object is changed according to sync.

bool	synchronized () const
	Return true if the anti partner chould be changed automatically when this object is changed.

void	synchronize ()
	If there is an anti-partner, update this object to have correct anti-properties.

void	massGenerator (tMassGenPtr)
	Set the mass generator object.

tMassGenPtr	massGenerator () const
	Get the mass generator object.

void	widthGenerator (tWidthGeneratorPtr)
	Set the width generator object.

tWidthGeneratorPtr	widthGenerator () const
	Get the width generator object.

void	variableRatio (bool varRatio)
	Specify if the branching ratio of the Particle instances should vary with their masses.

bool	variableRatio () const
	Return true if the branching ratio should vary with the mass of the Particle instance.

void	persistentOutput (PersistentOStream &os) const
	Function used to write out object persistently.

void	persistentInput (PersistentIStream &is, int version)
	Function used to read in object persistently.

Public Member Functions inherited from ThePEG::Interfaced
virtual	~Interfaced ()
	Empty virtual destructor.

virtual bool	defaultInit ()
	Functions which are to be used during the actual event generation, after the setup is complete.

PPtr	getParticle (PID) const
	Create a new Particle instance given a id number.

PDPtr	getParticleData (PID) const
	Return a pointer to the ParticleData object corresponding to the given id number.

bool	used () const
	Returns true if this object has actally been used.

void	useMe () const
	Should be called to indicate that this object has actually been used.

tEGPtr	generator () const
	Return a pointer to the EventGenerator controlling the run.

void	persistentOutput (PersistentOStream &os) const
	Function used to write out object persistently.

void	persistentInput (PersistentIStream &is, int version)
	Function used to read in object persistently.

Public Member Functions inherited from ThePEG::InterfacedBase
virtual	~InterfacedBase ()
	The virtual (empty) destructor;.

string	fullName () const
	Returns the full name of this object including its path, e.g.

string	name () const
	Returns the name of this object, without the path.

string	path () const
	Returns the path to this object including the trailing '/'.

string	comment () const
	Returns a comment assigned to this object.

void	setup (istream &is)
	Read setup info from a standard istream is.

void	update ()
	Calls the doupdate() function with recursion prevention.

void	init ()
	Calls the doinit() function with recursion prevention.

virtual bool	preInitialize () const
	Return true if this object needs to be initialized before all other objects (except those for which this function also returns true).

void	initrun ()
	Calls the doinitrun() function with recursion prevention.

void	finish ()
	Calls the dofinish() function with recursion prevention.

void	touch ()
	This function should be called every time something in this object has changed in a way that a sanity check with update() is needed.

void	reset ()
	Set the state of this object to uninitialized.

void	clear ()
	Calls reset() and unTouch().

InitState	state () const
	Return the state of initialization of this object.

bool	locked () const
	Return true if the BaseRepository is not allowed to change the state of this object.

bool	touched () const
	Return true if the state of this object has been changed since the last call to update().

void	persistentOutput (PersistentOStream &os) const
	Function used to write out object persistently.

void	persistentInput (PersistentIStream &is, int version)
	Function used to read in object persistently.

virtual void	debugme () const
	Print out debugging information for this object on std::cerr.

Public Member Functions inherited from ThePEG::Base
virtual	~Base ()
	The virtual destructor.

void	debug () const
	Print out debugging information for this object on std::cerr.

virtual void	debugme () const
	Print out debugging information for this object on std::cerr.

Public Member Functions inherited from ThePEG::Pointer::ReferenceCounted
CounterType	referenceCount () const
	Return the reference count.

Public Member Functions inherited from ThePEG::Named
	Named (const string &newName=string())
	Constructor with name.

	Named (const Named &)=default
	Explicit default copy-constructor (too avoid compiler warnings)

const string &	name () const
	Return name.

bool	operator== (const Named &other) const
	Test for equality.

bool	operator< (const Named &other) const
	Lexicographical comparison.

Standard Interfaced functions.
static ClassDescription< MixedParticleData >	initMixedParticleData
	The static object used to initialize the description of this class.

Energy	_deltam
	Mixing parameters.

Energy	_deltagamma
	The width difference.

double	_pqmag
	The magnitude of \(p/q\).

double	_pqphase
	The phase of \(p/q\).

Complex	_pq
	\(p/q\)

double	_zmag
	The magnitude of \(z\).

double	_zphase
	The phase of \(z\).

Complex	_z
	The \(z\) parameter.

double	_x
	The \(x\) mixing variable.

double	_y
	the \(y\) mixing variable

pair< double, double >	_prob
	The time-integrated mixing probabilities.

virtual void	doinit ()
	Initialize this object after the setup phase before saving an EventGenerator to disk.

void	setDeltaM (Energy)
	Function for the interface to set the mass difference.

void	setDeltaGamma (Energy)
	Function for the interface to set the width difference.

void	setPQMagnitude (double)
	Function for the interface to set the magnitude of p/q.

void	setPQPhase (double)
	Function for the interface to set the phase of p/q.

void	setZMagnitude (double)
	Function for the interface to set the magnitude of z.

void	setZPhase (double)
	Function for the interface to set the phase of z.

MixedParticleData &	operator= (const MixedParticleData &)=delete
	The assignment operator is private and must never be called.

The Create methods are special interfaces for ParticleData
classes.
Energy	deltaM () const
	Mixing parameters.

Energy	deltaGamma () const
	The width difference.

Complex	pq () const
	\(p/q\)

Complex	z () const
	\(z\)

double	x () const
	The \(x\) mixing variable.

double	y () const
	the \(y\) mixing variable

pair< double, double >	prob () const
	The time-integrated mixing probabilities.

pair< bool, Length >	generateLifeTime () const
	For a given paricle decide is it undergoes mixing and generate the lifetime.

pair< Complex, Complex >	mixingAmplitudes (Length, bool) const
	The amplitudes for the different states.

static PDPtr	Create (long newId, string newPDGName)
	Create a Particle which is its own anti-particle.

static PDPair	Create (long newId, string newPDGName, string newAntiPDGName)
	Create a particle - anti particle pair.

Functions used by the persistent I/O system.
void	persistentOutput (PersistentOStream &os) const
	Function used to write out object persistently.

void	persistentInput (PersistentIStream &is, int version)
	Function used to read in object persistently.

static void	Init ()
	The standard Init function used to initialize the interfaces.

	MixedParticleData (long newId, string newPDGName)
	Protected constructor only to be used by subclasses or by the Create method.

virtual PDPtr	pdclone () const
	ParticleData clone method.

Additional Inherited Members
Public Types inherited from ThePEG::ParticleData
typedef Selector< tDMPtr >	DecaySelector
	A selector of DecayMode objects.

Public Types inherited from ThePEG::InterfacedBase
enum	InitState { initializing = -1 , uninitialized = 0 , initialized = 1 , runready = 2 }
	Enumeration reflecting the state of an InterfacedBase object. More...

Public Types inherited from ThePEG::Pointer::ReferenceCounted
typedef unsigned int	CounterType
	The integer type used for counting.

Static Public Member Functions inherited from ThePEG::ParticleData
static PDPtr	Create (PID newId, const string &newPDGName)
	Create a Particle which is its own anti-particle.

static PDPair	Create (PID newId, const string &newPDGName, const string &newAntiPDGName)
	Create a particle - anti particle pair.

static void	Init ()

Static Public Member Functions inherited from ThePEG::Interfaced
static void	Init ()
	Standard Init function.

Static Public Member Functions inherited from ThePEG::InterfacedBase
static void	Init ()
	Standard Init function.

Static Public Member Functions inherited from ThePEG::Base
static void	Init ()
	The standard Init function used to initialize the interfaces.

Public Attributes inherited from ThePEG::Pointer::ReferenceCounted
const unsigned long	uniqueId
	The unique ID.

Protected Member Functions inherited from ThePEG::ParticleData
virtual void	doupdate ()
	Check sanity of the object during the setup phase.

virtual void	rebind (const TranslationMap &trans)
	Rebind pointer to other Interfaced objects.

virtual IVector	getReferences ()
	Return a vector of all pointers to Interfaced objects used in this object.

virtual void	doinitrun ()
	Initialize this object.

void	addDecayMode (tDMPtr)
	Add a decay mode for this particle.

void	removeDecayMode (tDMPtr)
	Remove a decay mode for this particle.

virtual IBPtr	clone () const
	Make a simple clone of this object.

virtual IBPtr	fullclone () const
	Make a clone of this object, possibly modifying the cloned object to make it sane.

	ParticleData (PID newId, const string &newPDGName)
	Protected constructor only to be used by subclasses or by the Create method.

virtual void	readSetup (istream &is)
	Read setup info from a standard stream.

Protected Member Functions inherited from ThePEG::Interfaced
void	reporeg (IBPtr object, string name) const
	Register the given object in the Repository with the given name in a subdirectory with the same name as this object.

template<typename PtrT >
bool	setDefaultReference (PtrT &ptr, string classname, string objectname)
	If the pointer, ptr, to an object is not set, create an object of class classname and register it with the Repository with the given objectname in a sib-directory with the same name as this object.

	Interfaced ()
	Protected default constructor.

	Interfaced (const string &newName)
	Protected constructor taking a name as argument.

	Interfaced (const Interfaced &i)
	Protected copy-constructor.

void	setGenerator (tEGPtr generator)
	Protected function to reset the generator pointer, required for automatic decayer generation in Herwig++ BSM models.

Protected Member Functions inherited from ThePEG::InterfacedBase
virtual void	dofinish ()
	Finalize this object.

	InterfacedBase ()
	Protected default constructor.

	InterfacedBase (string newName)
	Protected constructor with the name given as argument.

	InterfacedBase (const InterfacedBase &i)
	Protected copy-constructor.

Protected Member Functions inherited from ThePEG::Pointer::ReferenceCounted
	ReferenceCounted ()
	Default constructor.

	ReferenceCounted (const ReferenceCounted &)
	Copy-constructor.

ReferenceCounted &	operator= (const ReferenceCounted &)
	Assignment.

Protected Member Functions inherited from ThePEG::Named
const Named &	operator= (const Named &other)
	Assignment.

const string &	name (const string &newName)
	Set new name.

Static Protected Member Functions inherited from ThePEG::ParticleData
static void	antiSetup (const PDPair &pap)
	Used by subclasses or by the Create method to setup anti-relationship.

Static Protected Member Functions inherited from ThePEG::Interfaced
static void	registerRepository (IBPtr)
	Register an Interfaced object with the Repository.

static void	registerRepository (IBPtr, string newName)
	Register an Interfaced object with the Repository, giving it a name.

Detailed Description

The MixedParticleData class is designed to store the particle data for particles which undergo mixing with their anti-particle, e.g.

\(B^0-\bar{B}^0\), \(B_s^0-\bar{B}_s^0\), \(D^0-\bar{D}^0\).

The key parameters are the mass difference between the heavier and lighter states, \(\Delta m = m_H-m_L\), the width difference \(\Delta\Gamma = \Gamma_H-\Gamma_L\). While the mass difference is positive by definition the sign of the width difference must be determined experimentally. It should be noted that because the width difference is expected to be negative in the Standard Model many experiment results use the convention \(\Delta\Gamma = \Gamma_L - \Gamma_H\) so care should be taken.

In order to be as general as possible we have included the option of CPT violation, in addition to the violation of CP, in the mixing in this case the light and heavy eigenstates are given by

\[|M_L\rangle \propto p \sqrt{1-z}| M^0 \rangle + q \sqrt{1+z}|\bar{M}^0\rangle,\]

\[|M_H\rangle \propto p \sqrt{1+z}| M^0 \rangle - q \sqrt{1-z}|\bar{M}^0\rangle,\]

where \(p\), \(q\) and \(z\) are complex parameters with \(z=0\) if CPT is conserved.

This gives the time evolution of the states

\[|M^0_{\rm phys}(t)\rangle = (g_+(t)+zg_-(t))|M^0\rangle -sqrt{1-z^2}\frac{q}{p}g_-(t)|\bar{M}^0\rangle,\]

\[\bar{M}^-_{\rm phys}\rangle = (g_+(t)+zg_-(t))|\bar{M}^0\rangle -sqrt{1-z^2}\frac{p}{q}g_-(t)|M^0\rangle,\]

for particles initially in a pure particle or antiparticle state where

\[g_\pm(t)=\frac12\left(e^{-im_Ht-\frac12\Gamma_Ht} \pm e^{-im_Lt-\frac12\Gamma_Lt}\right).\]

See also: The interfaces defined for MixedParticleData.

Definition at line 50 of file MixedParticleData.h.

Constructor & Destructor Documentation

◆ MixedParticleData()

ThePEG::MixedParticleData::MixedParticleData ( )

inline

The default constructor.

Definition at line 57 of file MixedParticleData.h.

Member Function Documentation

◆ deltaGamma()

Energy ThePEG::MixedParticleData::deltaGamma ( ) const

inline

The width difference.

Definition at line 91 of file MixedParticleData.h.

References _deltagamma.

◆ deltaM()

Energy ThePEG::MixedParticleData::deltaM ( ) const

inline

Mixing parameters.

The mass difference

Definition at line 86 of file MixedParticleData.h.

References _deltam.

◆ doinit()

virtual void ThePEG::MixedParticleData::doinit ( )

protectedvirtual

Initialize this object after the setup phase before saving an EventGenerator to disk.

Exceptions

InitException if object could not be initialized properly.

Reimplemented from ThePEG::ParticleData.

◆ Init()

static void ThePEG::MixedParticleData::Init ( )

static

The standard Init function used to initialize the interfaces.

Called exactly once for each class by the class description system before the main function starts or when this class is dynamically loaded.

◆ operator=()

MixedParticleData & ThePEG::MixedParticleData::operator= ( const MixedParticleData & )

privatedelete

The assignment operator is private and must never be called.

In fact, it should not even be implemented.

◆ pdclone()

virtual PDPtr ThePEG::MixedParticleData::pdclone ( ) const

protectedvirtual

ParticleData clone method.

Reimplemented from ThePEG::ParticleData.

◆ persistentInput()

void ThePEG::MixedParticleData::persistentInput	(	PersistentIStream &	is,
		int	version
	)

Function used to read in object persistently.

Parameters

is	the persistent input stream read from.
version	the version number of the object when written.

◆ persistentOutput()

void ThePEG::MixedParticleData::persistentOutput ( PersistentOStream & os ) const

Function used to write out object persistently.

Parameters

os	the persistent output stream written to.

◆ pq()

Complex ThePEG::MixedParticleData::pq ( ) const

inline

\(p/q\)

Definition at line 96 of file MixedParticleData.h.

References _pq.

◆ prob()

pair< double, double > ThePEG::MixedParticleData::prob ( ) const

inline

The time-integrated mixing probabilities.

Definition at line 116 of file MixedParticleData.h.

References _prob.

◆ x()

double ThePEG::MixedParticleData::x ( ) const

inline

The \(x\) mixing variable.

Definition at line 106 of file MixedParticleData.h.

References _x.

◆ y()

double ThePEG::MixedParticleData::y ( ) const

inline

the \(y\) mixing variable

Definition at line 111 of file MixedParticleData.h.

References _y.

◆ z()

Complex ThePEG::MixedParticleData::z ( ) const

inline

\(z\)

Definition at line 101 of file MixedParticleData.h.

References _z.

Member Data Documentation

◆ _deltagamma

Energy ThePEG::MixedParticleData::_deltagamma

private

The width difference.

Definition at line 240 of file MixedParticleData.h.

Referenced by deltaGamma().

◆ _deltam

Energy ThePEG::MixedParticleData::_deltam

private

Mixing parameters.

The mass difference

Definition at line 235 of file MixedParticleData.h.

Referenced by deltaM().

◆ _pq

Complex ThePEG::MixedParticleData::_pq

private

\(p/q\)

Definition at line 255 of file MixedParticleData.h.

Referenced by pq().

◆ _pqmag

double ThePEG::MixedParticleData::_pqmag

private

The magnitude of \(p/q\).

Definition at line 245 of file MixedParticleData.h.

◆ _pqphase

double ThePEG::MixedParticleData::_pqphase

private

The phase of \(p/q\).

Definition at line 250 of file MixedParticleData.h.

◆ _prob

pair<double,double> ThePEG::MixedParticleData::_prob

private

The time-integrated mixing probabilities.

Definition at line 285 of file MixedParticleData.h.

Referenced by prob().

◆ _x

double ThePEG::MixedParticleData::_x

private

The \(x\) mixing variable.

Definition at line 275 of file MixedParticleData.h.

Referenced by x().

◆ _y

double ThePEG::MixedParticleData::_y

private

the \(y\) mixing variable

Definition at line 280 of file MixedParticleData.h.

Referenced by y().

◆ _z

Complex ThePEG::MixedParticleData::_z

private

The \(z\) parameter.

Definition at line 270 of file MixedParticleData.h.

Referenced by z().

◆ _zmag

double ThePEG::MixedParticleData::_zmag

private

The magnitude of \(z\).

Definition at line 260 of file MixedParticleData.h.

◆ _zphase

double ThePEG::MixedParticleData::_zphase

private

The phase of \(z\).

Definition at line 265 of file MixedParticleData.h.

◆ initMixedParticleData

ClassDescription<MixedParticleData> ThePEG::MixedParticleData::initMixedParticleData

staticprivate

The static object used to initialize the description of this class.

Indicates that this is a concrete class with persistent data.

Definition at line 218 of file MixedParticleData.h.

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

MixedParticleData.h

Public Member Functions

Standard Interfaced functions.

The Create methods are special interfaces for ParticleData

Functions used by the persistent I/O system.

Additional Inherited Members

Detailed Description

Constructor & Destructor Documentation

◆ MixedParticleData()

Member Function Documentation

◆ deltaGamma()

◆ deltaM()

◆ doinit()

◆ Init()

◆ operator=()

◆ pdclone()

◆ persistentInput()

◆ persistentOutput()

◆ pq()

◆ prob()

◆ x()

◆ y()

◆ z()

Member Data Documentation

◆ _deltagamma

◆ _deltam

◆ _pq

◆ _pqmag

◆ _pqphase

◆ _prob

◆ _x

◆ _y

◆ _z

◆ _zmag

◆ _zphase

◆ initMixedParticleData