Page MenuHomeHEPForge
Files F10881096

RemnantDecayer.h
No OneTemporary
Actions

RemnantDecayer.h
View Options

// -*- C++ -*-
#ifndef THEPEG_RemnantDecayer_H
#define THEPEG_RemnantDecayer_H
//
// This is the declaration of the RemnantDecayer class.
//
#include "ThePEG/PDT/Decayer.h"
#include "RemnantDecayer.fh"
#include "ThePEG/PDT/RemnantData.h"
#include "ThePEG/EventRecord/RemnantParticle.h"
#include "ThePEG/Handlers/PtGenerator.h"
namespace ThePEG {
/**
* The RemnantDecayer class is the base class to be used for all
* decayers capable of decaying a RemnantParticle object produced by a
* SoftRemnantHandler object. A derived class must implement the
* decay(const DecayMode &, const Particle &, Step &) function, while
* the decay(const DecayMode &, const Particle &) function should
* never be called.
*
* @see \ref RemnantDecayerInterfaces "The interfaces"
* defined for RemnantDecayer.
*/
class RemnantDecayer: public Decayer {
public:
/** A pointer to a PtGenerator object. */
typedef Ptr<PtGenerator>::pointer PtGPtr;
public:
/**
* Enumerate the options for how to distribute recoils in the hard
* subsystem when taking energy to produce remnants.
*/
enum RecoilOption {
boostAll, /**< Boost all particles in the hard subsystem. */
boostFinal, /**< Boost only final state particles in hard subsystem. */
copyFinal /**< Boost copies of final state particles in hard subsystem. */
};
public:
/** @name Standard constructors and destructors. */
//@{
/**
* The default constructor.
*/
inline RemnantDecayer();
/**
* The copy constructor.
*/
inline RemnantDecayer(const RemnantDecayer &);
/**
* The destructor.
*/
virtual ~RemnantDecayer();
//@}
public:
/** @name Virtual functions required by the Decayer class. */
//@{
/**
* Check if this decayer can perfom the decay specified by the
* given decay mode.
* @param dm the DecayMode describing the decay.
* @return true if this decayer can handle the given mode, otherwise false.
*/
virtual bool accept(const DecayMode & dm) const;
/**
* Return true if this Decayer need to access the full current step
* when a particle is decayed. If true is returned the standard
* Decay Handler will call the decay(const DecayMode&,const
* Particle&,Step&) function rather than the decay(const
* DecayMode&,const Particle&) function.
*/
virtual bool needsFullStep() const;
/**
* Perform a decay for a given DecayMode and a given Particle
* instance. This version allows the decaying particle to borrow
* energy/momentum from its sublings in the current step. This will
* be called by the standard DecayHandler if the needsFullStep()
* function returns true.
*
* @param dm the DecayMode describing the decay.
* @param p the Particle instance to be decayed.
* @param step the current step in which to find possible siblings to
* shuffle energy with.
* @return a ParticleVector containing the decay products.
*/
virtual ParticleVector decay(const DecayMode & dm, const Particle & p,
Step & step) const = 0;
/**
* Perform a decay for a given DecayMode and a given Particle instance.
* @param dm the DecayMode describing the decay.
* @param p the Particle instance to be decayed.
* @return a ParticleVector containing the decay products.
*/
virtual ParticleVector decay(const DecayMode & dm, const Particle & p) const;
//@}
/**
* Return true if this decayer can handle the extraction of the \a
* extracted parton from the given \a particle.
*/
virtual bool canHandle(tcPDPtr parent, tcPDPtr extracted) const;
/**
* Return true if this decayed can extract more than one parton from
* a particle.
*/
virtual bool multiCapable() const;
/**
* The option for how to distribute recoils in the hard subsystem
* when taking energy to produce remnants.
*/
inline RecoilOption recoilOption() const;
/**
* If true, do not boost a scattered lepton (and possible radiated
* photons) in a DIS event, to ensure that \f$x\f$ and \f$Q^2\f$ is
* unmodified.
*/
inline bool respectDISKinematics() const;
/**
* An object capable of generating an intrinsic transverse momentum
* of the created remnants.
*/
inline PtGPtr pTGenerator() const;
/**
* Static function to decay al remnants among the given \a
* particles. The decay products are inserted in the \a step
* provided.
* @return a vector of the non-remnant particles together with the
* remnant decay products.
*/
static tPVector decayRemnants(const tPVector & particles, Step & step);
protected:
/**
* Access the RemnantData object of a \a remnant.
*/
inline tRemPDPtr data(tcRemPPtr remnant) const;
/**
* Access the parent of a \a remnant.
*/
inline tcPPtr parent(tcRemPPtr remnant) const;
/**
* Access the vector of extracted particles of a \a remnant.
*/
inline const PVector & extracted(tcRemPPtr remnant) const;
/**
* Recursively find all particles produced from an extracted parton.
*/
virtual void fillSubSystem(tPPtr p, set<tPPtr> & sub) const;
/**
* Return the system of particles from the hard subsystem which may
* be used to shuffle momenta to get the remnants on-shell. In this
* version the particles are ordered in rapidity with the ones
* closest to the remnant direction comes first. Other orderings can
* be enforced by sub-classes.
*/
virtual tPVector getSubSystem(tcPPtr parent, tPPtr parton) const;
/**
* Return a small boost along the z-axis. To cure rounding errors
* when making large boosts it is sometimes necessary to correct the
* plus (or minus) lightcone component with a small boost along the
* z-axis. The resulting boost is constructed so that the momentum
* \a p0 would be transformed to have the sam z-value as the
* momentum \a p.
*/
static LorentzRotation getZBoost(const LorentzMomentum & p0,
const LorentzMomentum & p);
public:
/**
* Exception used if getSubSystem fails.
*/
struct SubSystemFail: public Exception {};
protected:
/** @name Standard Interfaced functions. */
//@{
/**
* Initialize this object after the setup phase before saving an
* EventGenerator to disk.
* @throws InitException if object could not be initialized properly.
*/
virtual void doinit() throw(InitException);
/**
* Return true if this object needs to be initialized before all
* other objects because it needs to extract cuts from the event file.
*/
virtual bool preInitialize() const;
//@}
public:
/** @name Functions used by the persistent I/O system. */
//@{
/**
* Function used to write out object persistently.
* @param os the persistent output stream written to.
*/
void persistentOutput(PersistentOStream & os) const;
/**
* Function used to read in object persistently.
* @param is the persistent input stream read from.
* @param version the version number of the object when written.
*/
void persistentInput(PersistentIStream & is, int version);
//@}
/**
* 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.
*/
static void Init();
protected:
/**
* If true, do not boost a scattered lepton (and possible radiated
* photons) in a DIS event, to ensure that \f$x\f$ and \f$Q^2\f$ is
* unmodified.
*/
mutable bool respectDIS;
private:
/**
* The option for how to distribute recoils in the hard subsystem
* when taking energy to produce remnants.
*/
RecoilOption theRecoilOption;
/**
* An object capable of generating an intrinsic transverse momentum
* of the created remnants.
*/
PtGPtr thePTGenerator;
private:
/**
* The static object used to initialize the description of this class.
* Indicates that this is a concrete class with persistent data.
*/
static AbstractClassDescription<RemnantDecayer> initRemnantDecayer;
/**
* The assignment operator is private and must never be called.
* In fact, it should not even be implemented.
*/
RemnantDecayer & operator=(const RemnantDecayer &);
};
}
#include "ThePEG/Utilities/ClassTraits.h"
namespace ThePEG {
/** @cond TRAITSPECIALIZATIONS */
/** This template specialization informs ThePEG about the
* base classes of RemnantDecayer. */
template <>
struct BaseClassTrait<RemnantDecayer,1> {
/** Typedef of the first base class of RemnantDecayer. */
typedef Decayer NthBase;
};
/** This template specialization informs ThePEG about the name of
* the RemnantDecayer class and the shared object where it is defined. */
template <>
struct ClassTraits<RemnantDecayer>
: public ClassTraitsBase<RemnantDecayer> {
/** Return a platform-independent class name */
static string className() { return "ThePEG::RemnantDecayer"; }
};
/** @endcond */
}
#include "RemnantDecayer.icc"
#ifndef ThePEG_TEMPLATES_IN_CC_FILE
// #include "RemnantDecayer.tcc"
#endif
#endif /* THEPEG_RemnantDecayer_H */

File Metadata

Mime Type
text/x-c++
Expires
Sat, May 3, 5:52 AM (17 h, 15 m)
Storage Engine
blob
Storage Format
Raw Data
Storage Handle
4982848
Default Alt Text
RemnantDecayer.h (8 KB)

Event Timeline