The ElectronCloudFinderProcessor searches for hits and groups contiguous areas to track candidates. More...

#include <ElectronCloudFinderProcessor.h>

Inheritance diagram for marlintpc::ElectronCloudFinderProcessor:

Public Member Functions
virtual Processor *	newProcessor ()

	ElectronCloudFinderProcessor ()

virtual void	init ()
	Called at the begin of the job before anything is read. More...

virtual void	processRunHeader (EVENT::LCRunHeader *run)
	Called for every run.

virtual void	processEvent (EVENT::LCEvent *evt)
	Called for every event - the working horse.

virtual void	check (EVENT::LCEvent *evt)

virtual void	end ()
	Called after data processing for clean up.

Static Protected Member Functions
static bool	comparePulses (std::pair< lcio::TrackerPulse , bool > firstSortingPair, std::pair< lcio::TrackerPulse , bool > secondSortingPair)
	A special function for the STL list::sort algorithm comparing pairs of TDC TrackerPulses (and bools)

Protected Attributes
std::string	_inputTrackerPulsesCollectionName
	the name of the collection the input pulses will be stored under

std::string	_outputTrackerHitsCollectionName
	the name of the collection the output hits will be stored under

bool	_outputHitsTransient
	Give the status which is set to the transient flag of the output collection. More...

float	_vDrift

float	_maxTimeSpread

int	_minHitSize

int	_maxHitSize

bool	_negativeZDirection

float	_maxDriftDistance

NeighbouringPadHandler *	myNeighbouringPadHandler
	Create an object which holds the information about the neighbourship of all pads.

Detailed Description

The ElectronCloudFinderProcessor searches for hits and groups contiguous areas to track candidates.

Using PadRowLayout2D from GEAR (RectangularPadRowLayout or FixedPadSizeDiskLayout) the agorithm searches for contiguous areas. Contiguous pulses in one pad row are grouped as hit candidates, then the hit coordinates are calculated using the centre of gravity method. The hits in one contiguous area are filled into a track candidate.

Attention: This processor only performs the search. The tracks are not seeded, i. e. the track paramaters of the track candidates are not set. They are just containers to hold the hits belonging to one track.

If MarlinTPC is compiled with the $MARLIN_DEBUG option there is a lot of debug output. Use the steering file to reduce it / switch it off.

Author: Martin Killenberg, University of Bonn (derived from HitTrackFinderTopoProcessor); Oliver Schaefer, University of Rostock

Todo:

Implement calculation of z-coordinate by drift velocity

Improve z cut. Currently it does not use topological information which can cause problems with curlers.

Input - Prerequisites

A Collection of TrackerPulses
GEAR TPCParameters with maxDriftLength and a pad layout (RectangularPadRowLayout or FixedPadSizeDiskLayout)
tpcconddata::TPCConditions for the drift velicity (optionally provided as processor parameter)
Todo:
Handling of dead and noisy channels.

Output

Collection of Hits
Collection of track candidates

Parameters

InputTrackerPulses	Name of input TrackerPulses collection (default: TPCPulses)
OutputTrackerHits	Name of output TrackerHits collection (default: TPCHits)
OutputTrackCandidates	Name of output Tracks collection (default: TPCTrackCandidates)
InputTPCConditions	`OPTIONAL:` Name of the input collection containing the TPC conditions data (default: tpcconddata::TPCConditions::getDefaultColName() )
SetOutputHitsTransient	If not 0 the output collection is set transient (default: 0)
SetOutputTrackCandidatesTransient	If not 0 the output collection is set transient (default: 0)
MaxEmptyPads	Maximum number of consecuitve empty pads in cluster (default: 1)
MinHitSize	Minimum size of hit / Minimum number of Pads (default: 1)
MaxTimeSpread	Maximum time between pulses in a cluster [in ns] (default: 200)
VDrift	`OPTIONAL:` Set drift velocity in case there is no conditions data [in mm/us] (default: 0)
NegativeZDirection	Set to 1 for the second half TPC, which look into the negative z direction (default: 0)

The drift velocity should normally come from the conditions data. This can be overwritten using this optional parameter. Do not set it in case you want to use vDrift from the CDDB!

Constructor & Destructor Documentation

marlintpc::ElectronCloudFinderProcessor::ElectronCloudFinderProcessor ( )

description of the processor which will be displayed in the steering file autometicly generated by marlin (use MarlinTPC -x (XML-format) or MarlinTPXC -l (text format))

References _inputTrackerPulsesCollectionName, _outputHitsTransient, and _outputTrackerHitsCollectionName.