org.lcsim.mc.fast.tracking.fix

Class FastMCTrackFactory

java.lang.Object

org.lcsim.mc.fast.tracking.fix.FastMCTrackFactory

public class FastMCTrackFactory
extends Object

Author:

jstrube This class creates a new FastMC Track. It is used as the interface between the track measurement and the detector. Since Track doesn't know anything about the magnetic field, and the material, it cannot transport its own parameters. Changing the reference point of a track requires swimming; it is therefore done in this class.

Field Summary

Fields

Modifier and Type	Field and Description
private double	_Bz
private ConditionsManager	_manager
private SimpleTables	_simpleTables
private HelixSwimmer	_swimmer
private TrackResolutionTables	_tables
private static SpacePoint	pDummy
private static Random	rDummy

Constructor Summary

Constructors

Constructor and Description
FastMCTrackFactory(EventHeader event, boolean beamConstraint) This constructor obtains the necessary information for construction like the field and the resolution tables from the event.
FastMCTrackFactory(String detectorName, double field, boolean beamConstraint) This constructor is only to be used by unit tests.

Method Summary

Methods

Modifier and Type	Method and Description
Track	getTrack(Hep3Vector momentum, Hep3Vector location, int charge)
Track	getTrack(MCParticle part) Creates a track from an MCParticle
Track	getTrack(SpaceVector momentum, SpacePoint location, int charge) Creates a new Track with the given parameters.
Track	getTrack(SpaceVector momentum, SpacePoint location, int charge, Random random) Creates a new Track with the given parameters.
Track	getTrack(SpaceVector momentum, SpacePoint location, SpacePoint referencePoint, int charge) Creates a new Track with the given parameters.
Track	getTrack(SpaceVector momentum, SpacePoint location, SpacePoint referencePoint, int charge, Random random) Returns a new Track object initialized with the given values, and with its parameters smeared according to the Tables that are read from the detector.
Track	getTrack(SpaceVector momentum, SpacePoint location, SpacePoint referencePoint, int charge, Random random, boolean shouldISmear) This version is only to be used in unit tests.
Track	getUnsmearedTrack(MCParticle part) Creates a track from an MCParticle without smearing the parameters
void	setNewReferencePoint(Track track, SpacePoint referencePoint) Swims the Track to a new reference point and calculates the parameters anew.
private static LCIOParameters	smearParameters(LCIOParameters oldParams, SymmetricMatrix sm, Random random) Smears the measurement matrix with a Gaussian error

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

_tables

private TrackResolutionTables _tables

_simpleTables

private SimpleTables _simpleTables

_manager

private ConditionsManager _manager

_Bz

private double _Bz

_swimmer

private HelixSwimmer _swimmer

rDummy

private static Random rDummy

pDummy

private static SpacePoint pDummy

Constructor Detail

FastMCTrackFactory

public FastMCTrackFactory(EventHeader event,
                  boolean beamConstraint)

This constructor obtains the necessary information for construction like the field and the resolution tables from the event.

Parameters:

event - The current event

beamConstraint - A switch to obtain the resolution tables with or without beamconstraint

FastMCTrackFactory

public FastMCTrackFactory(String detectorName,
                  double field,
                  boolean beamConstraint)

This constructor is only to be used by unit tests. It will instantiate the Factory with a detector name and a field.

Method Detail

getTrack

public Track getTrack(MCParticle part)

Creates a track from an MCParticle

Parameters:

part - The MCParticle that is transformed to a track

Returns:

A FastMCTrack instance that contains information about the particle that was used as input

getUnsmearedTrack

public Track getUnsmearedTrack(MCParticle part)

Creates a track from an MCParticle without smearing the parameters

Parameters:

part - The MCParticle that is transformed to a track

Returns:

A FastMCTrack instance that contains information about the particle that was used as input

getTrack

public Track getTrack(SpaceVector momentum,
             SpacePoint location,
             int charge)

Creates a new Track with the given parameters. See ##getTrack(SpacePoint, SpacePoint, SpacePoint, int, Random) for details.

Parameters:

momentum - The momentum at a given location

location - The location where the momentum is measured

charge - The charge of the Particle that created the Track

Returns:

A new NewTFastMCTrackect with the desired properties

getTrack

public Track getTrack(SpaceVector momentum,
             SpacePoint location,
             int charge,
             Random random)

Creates a new Track with the given parameters. See ##getTrack(SpacePoint, SpacePoint, SpacePoint, int, Random) for details.

Parameters:

momentum - The momentum at a given location

location - The location where the momentum is measured

charge - The charge of the Particle that created the Track

random - A random generator instance

Returns:

A new NewTrFastMCTrackct with the desired properties

getTrack

public Track getTrack(SpaceVector momentum,
             SpacePoint location,
             SpacePoint referencePoint,
             int charge)

Creates a new Track with the given parameters. See ##getTrack(SpacePoint, SpacePoint, SpacePoint, int, Random) for details.

Parameters:

momentum - The momentum at a given location

location - The location where the momentum is measured

referencePoint - The point with respect to which the parameters are measured

charge - The charge of the Particle that created the Track

Returns:

A new NewTrFastMCTrackct with the desired properties

getTrack

public Track getTrack(SpaceVector momentum,
             SpacePoint location,
             SpacePoint referencePoint,
             int charge,
             Random random,
             boolean shouldISmear)

This version is only to be used in unit tests.

Parameters:

momentum - The momentum at a given location

location - The location where the momentum is measured

referencePoint - The point with respect to which the parameters are measured

charge - The charge of the Particle that created the Track

random - A random generator instance

shouldISmear - This parameter switches smearing on/off. It should always be true except in Unit tests.

Returns:

A new NewTracFastMCTrack with the desired properties

getTrack

public Track getTrack(SpaceVector momentum,
             SpacePoint location,
             SpacePoint referencePoint,
             int charge,
             Random random)

Returns a new Track object initialized with the given values, and with its parameters smeared according to the Tables that are read from the detector. This method can take a random seed

Parameters:

momentum - The momentum at a given location

location - The location where the momentum is measured

referencePoint - The point with respect to which the parameters are measured

charge - The charge of the Particle that created the Track

random - A random generator instance

Returns:

A new NewTraFastMCTrackt with the desired properties

getTrack

public Track getTrack(Hep3Vector momentum,
             Hep3Vector location,
             int charge)

setNewReferencePoint

public void setNewReferencePoint(Track track,
                        SpacePoint referencePoint)

Swims the Track to a new reference point and calculates the parameters anew. It has to be done here, because it involves swimming, which has to be done outside the track

Parameters:

track - The track to be swum

referencePoint - The new reference point for the track to swim to

smearParameters

private static LCIOParameters smearParameters(LCIOParameters oldParams,
                             SymmetricMatrix sm,
                             Random random)

Smears the measurement matrix with a Gaussian error

Parameters:

oldParams - The unsmeared Parameters

errorMatrix - The measurement error matrix

random - A random generator

Returns:

A new set of smeared parameters