marlin::SimpleFastMCProcessor Class Reference

A simple smearing "Monte Carlo" processor. More...

#include <SimpleFastMCProcessor.h>

Inheritance diagram for marlin::SimpleFastMCProcessor:

List of all members.

Public Member Functions
virtual Processor *	newProcessor ()
	Returns a new instance of the processor.
virtual void	init ()
	Initializes ...
virtual void	processRunHeader (LCRunHeader *run)
	Called for every run.
virtual void	processEvent (LCEvent *evt)
	Updates all registered conditions handlers and adds the data to the event.
virtual void	check (LCEvent *evt)
	Creates some checkplots.
virtual void	end ()
	Called after data processing for clean up.
Protected Attributes
std::string	_inputCollectionName
	Input collection name.
std::string	_recoParticleCollectionName
	Ouput collection names.
std::string	_mcTruthCollectionName
float	_momentumCut
	Momentum cut in GeV.
FloatVec	_initChargedRes
	Resolutions of charged particles.
FloatVec	_initPhotonRes
	Resolutions of photons.
FloatVec	_initNeutralHadronRes
	Resolutions of photons.
IRecoParticleFactory *	_factory
	The particle factory.
int	_nRun
int	_nEvt

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Detailed Description

A simple smearing "Monte Carlo" processor.

It creates ReconstructedParticles from MCParticles according to the resolution that is specified for the particle type, one of:

• photon
• charged: e+-,mu+-,pi+-,K+-,p+-,....
• neutral hadron: K0L, n, Lambda0,...

The resolutions for charged particles are given as delta(1/P) for a certain polar angle range (mapped to [0.,pi/2.]), e.g.
ChargedResolution   .7e-5   0.   3.141593/2.
sets the resolution for all charged particles to 0.7*10^-5.
Specifying different resolutions for different polar angle ranges allows to mimic degrading detector performance in the very forward region.
The energy of the charged ReconstructedParticles is set from the "measured" momentum using the energy momentum relation for electrons and muons and assuming the pion mass for all other charged tracks.
The resolutions for neutral particles are given as A and B for a certain polar angle range, where dE/E = A "+" B / sqrt(E/GeV), e.g.
NeutralHadronResolution   0.03   .30   0.   3.141593/2.
sets the resolution for all neutral hadrons to 3% "+" 30% / sqrt( E /GeV ). The resolution for gammas is specified in PhotonResolution
No ReconstructedParticles are created if there is no resolution defined at that polar angle, e.g.
PhotonResolution   .7e-5   0.083   3.141593/2.
effectively limits the acceptance region for photons to theta > 83mrad.

A collection of LCRelations, called "MCTruthMapping" holds the relation between the ReconstructedParticles and their proper MCParticles.

Input - Prerequisites

A collection of MCParticles (the MCPArticle collection).

Output

• ReconstructedParticles: the collection of reconstructed particles
• MCTruthMapping: holds LCRelations that map the ReconstructedParticles to their proper MCParticles

Parameters:

ChargedResolution	Resolution of charged particles in polar angle range: d(1/P) th_min th_max
InputCollectionName	Name of the MCParticle input collection
MomentumCut	No reconstructed particles are produced for smaller momenta (in [GeV])
NeutralHadronResolution	Resolution dE/E=A+B/sqrt(E/GeV) of neutral hadrons in polar angle range: A B th_min th_max
PhotonResolution	Resolution dE/E=A+B/sqrt(E/GeV) of photons in polar angle range: A B th_min th_max
RecoParticleCollectionName	default is "ReconstructedParticles"
MCTruthMappingCollectionName	default is "MCTruthMapping"

Author:

F. Gaede, DESY

Version:

Id

SimpleFastMCProcessor.h,v 1.4 2007/07/04 12:13:06 gaede Exp

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

• SimpleFastMCProcessor.h
• SimpleFastMCProcessor.cc

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