#include <Digitizer.h>

Public Types
using	SC = SpaceCharge< float >

Public Member Functions
	Digitizer ()
	Default constructor.

	~Digitizer ()
	Destructor.

	Digitizer (const Digitizer &)=delete

Digitizer &	operator= (const Digitizer &)=delete

void	init ()
	Initializer.

void	process (const std::vector< o2::tpc::HitGroup > &hits, const int eventID, const int sourceID=0)

void	flush (std::vector< o2::tpc::Digit > &digits, o2::dataformats::MCTruthContainer< o2::MCCompLabel > &labels, std::vector< o2::tpc::CommonMode > &commonModeOutput, bool finalFlush=false)

void	setSector (Sector sec)

void	setStartTime (double time)

void	setOutputDigitTimeOffset (double offset)
	Set mOutputDigitTimeOffset.

void	setEventTime (double time)

void	setContinuousReadout (bool isContinuous)

bool	isContinuousReadout ()

void	setUseSCDistortions (const SCDistortionType &distortionType, const TH3 *hisInitialSCDensity)

void	setUseSCDistortions (SC *spaceCharge)

void	setSCDistortionsDerivative (SC *spaceCharge)

void	setUseSCDistortions (std::string_view finp)

void	setVDrift (float v)

void	setTDriftOffset (float t)

void	setDistortionScaleType (int distortionScaleType)

int	getDistortionScaleType () const

void	setLumiScaleFactor ()

void	setMeanLumiDistortions (float meanLumi)

void	setMeanLumiDistortionsDerivative (float meanLumi)

void	recalculateDistortions ()
	in case of scaled distortions, the distortions can be recalculated to ensure consistent distortions and corrections

Detailed Description

This is the digitizer for the ALICE GEM TPC. It is the main class and steers all relevant physical processes for the signal formation in the detector.

Transformation of energy deposit of the incident particle to a number of primary electrons
Drift and diffusion of the primary electrons while moving in the active volume towards the readout chambers (ElectronTransport)
Amplification of the electrons in the stack of four GEM foils (GEMAmplification)
Induction of the signal on the pad plane, including a spread of the signal due to the pad response (SignalInduction)
Shaping and further signal processing in the Front-End Cards (SampaProcessing) The such created Digits and then sorted in an intermediate Container (DigitContainer) and after processing of the full event/drift time summed up and sorted as Digits into a vector which is then passed further on

Definition at line 53 of file Digitizer.h.

Member Typedef Documentation

◆ SC

using o2::tpc::Digitizer::SC = SpaceCharge<float>

Definition at line 56 of file Digitizer.h.

Constructor & Destructor Documentation

◆ Digitizer() [1/2]

Digitizer::Digitizer ( )

default

Default constructor.

◆ ~Digitizer()

Digitizer::~Digitizer ( )

default

Destructor.

◆ Digitizer() [2/2]

o2::tpc::Digitizer::Digitizer ( const Digitizer & )

delete

Member Function Documentation

◆ flush()

void Digitizer::flush	(	std::vector< o2::tpc::Digit > &	digits,
		o2::dataformats::MCTruthContainer< o2::MCCompLabel > &	labels,
		std::vector< o2::tpc::CommonMode > &	commonModeOutput,
		bool	finalFlush = `false`
	)

Flush the data

Parameters

digits	Container for the digits
labels	Container for the MC labels
commonModeOutput	Output container for the common mode
finalFlush	Flag whether the whole container is dumped

Definition at line 168 of file Digitizer.cxx.

◆ getDistortionScaleType()

int o2::tpc::Digitizer::getDistortionScaleType ( ) const

inline

Definition at line 136 of file Digitizer.h.

◆ init()

void Digitizer::init ( )

Initializer.

Definition at line 42 of file Digitizer.cxx.

◆ isContinuousReadout()

bool o2::tpc::Digitizer::isContinuousReadout ( )

inline

Option to retrieve triggered / continuous readout

Returns: true for continuous readout

Definition at line 111 of file Digitizer.h.

◆ operator=()

Digitizer & o2::tpc::Digitizer::operator= ( const Digitizer & )

delete

◆ process()

void Digitizer::process	(	const std::vector< o2::tpc::HitGroup > &	hits,
		const int	eventID,
		const int	sourceID = `0`
	)

Process a single hit group

Parameters

hits	Container with TPC hit groups
eventID	ID of the event to be processed
sourceID	ID of the source to be processed

Reserve space in the digit container for the current event

obtain max drift_time + hitTime which can be processed

Remove electrons that end up more than three sigma of the hit's average diffusion away from the current sector boundary

The energy loss stored corresponds to nElectrons

in us

TODO: add primary ions to space-charge density

Loop over electrons

Drift and Diffusion

in us

the absolute time needs to be within the readout limits (otherwise negative times would all be accumulated in the 0-th timebin further below)

Attachment

Remove electrons that end up outside the active volume

When the electron is not in the sector we're processing, abandon

Compute digit position and check for validity

Remove digits the end up outside the currently produced sector

Electron amplification

TODO: add ion backflow to space-charge density

end of loop over electrons

Definition at line 52 of file Digitizer.cxx.

◆ recalculateDistortions()

void Digitizer::recalculateDistortions ( )

in case of scaled distortions, the distortions can be recalculated to ensure consistent distortions and corrections

Definition at line 252 of file Digitizer.cxx.

◆ setContinuousReadout()

void o2::tpc::Digitizer::setContinuousReadout ( bool isContinuous )

inline

Switch for triggered / continuous readout

Parameters

isContinuous - false for triggered readout, true for continuous readout

Definition at line 107 of file Digitizer.h.

◆ setDistortionScaleType()

void o2::tpc::Digitizer::setDistortionScaleType ( int distortionScaleType )

inline

Definition at line 135 of file Digitizer.h.

◆ setEventTime()

void o2::tpc::Digitizer::setEventTime ( double time )

inline

Set the time of the event to be processed

Parameters

time	Time of the event

Definition at line 103 of file Digitizer.h.

◆ setLumiScaleFactor()

void Digitizer::setLumiScaleFactor ( )

Definition at line 236 of file Digitizer.cxx.

◆ setMeanLumiDistortions()

void Digitizer::setMeanLumiDistortions ( float meanLumi )

Definition at line 242 of file Digitizer.cxx.

◆ setMeanLumiDistortionsDerivative()

void Digitizer::setMeanLumiDistortionsDerivative ( float meanLumi )

Definition at line 247 of file Digitizer.cxx.

◆ setOutputDigitTimeOffset()

void o2::tpc::Digitizer::setOutputDigitTimeOffset ( double offset )

inline

Set mOutputDigitTimeOffset.

Definition at line 99 of file Digitizer.h.

◆ setSCDistortionsDerivative()

void Digitizer::setSCDistortionsDerivative ( SC * spaceCharge )

Parameters

spaceCharge unique pointer to spaceCharge object

Definition at line 202 of file Digitizer.cxx.

◆ setSector()

void o2::tpc::Digitizer::setSector ( Sector sec )

inline

Set the sector to be processed

Parameters

sec	Sector to be processed

Definition at line 88 of file Digitizer.h.

◆ setStartTime()

void Digitizer::setStartTime ( double time )

Set the start time of the first event

Parameters

time	Time of the first event

Definition at line 224 of file Digitizer.cxx.

◆ setTDriftOffset()

void o2::tpc::Digitizer::setTDriftOffset ( float t )

inline

Definition at line 133 of file Digitizer.h.

◆ setUseSCDistortions() [1/3]

void Digitizer::setUseSCDistortions	(	const SCDistortionType &	distortionType,
		const TH3 *	hisInitialSCDensity
	)

Enable the use of space-charge distortions and provide space-charge density histogram as input

Parameters

distortionType	select the type of space-charge distortions (constant or realistic)
hisInitialSCDensity	optional space-charge density histogram to use at the beginning of the simulation
nZSlices	number of grid points in z, must be (2**N)+1
nPhiBins	number of grid points in phi
nRBins	number of grid points in r, must be (2**N)+1

Definition at line 181 of file Digitizer.cxx.

◆ setUseSCDistortions() [2/3]

void Digitizer::setUseSCDistortions ( SC * spaceCharge )

Enable the use of space-charge distortions and provide SpaceCharge object as input

Parameters

spaceCharge unique pointer to spaceCharge object

Definition at line 194 of file Digitizer.cxx.

◆ setUseSCDistortions() [3/3]

void Digitizer::setUseSCDistortions ( std::string_view finp )

Enable the use of space-charge distortions by providing global distortions and global corrections stored in a ROOT file The storage of the values should be done by the methods provided in the SpaceCharge class

Parameters

file	containing distortions

Definition at line 209 of file Digitizer.cxx.

◆ setVDrift()

void o2::tpc::Digitizer::setVDrift ( float v )

inline

Definition at line 132 of file Digitizer.h.

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

/home/runner/work/AliceO2/AliceO2/Detectors/TPC/simulation/include/TPCSimulation/Digitizer.h
/home/runner/work/AliceO2/AliceO2/Detectors/TPC/simulation/src/Digitizer.cxx

Public Types

Public Member Functions

Detailed Description

Member Typedef Documentation

◆ SC

Constructor & Destructor Documentation

◆ Digitizer() [1/2]

◆ ~Digitizer()

◆ Digitizer() [2/2]

Member Function Documentation

◆ flush()

◆ getDistortionScaleType()

◆ init()

◆ isContinuousReadout()

◆ operator=()

◆ process()

◆ recalculateDistortions()

◆ setContinuousReadout()

◆ setDistortionScaleType()

◆ setEventTime()

◆ setLumiScaleFactor()

◆ setMeanLumiDistortions()

◆ setMeanLumiDistortionsDerivative()

◆ setOutputDigitTimeOffset()

◆ setSCDistortionsDerivative()

◆ setSector()

◆ setStartTime()

◆ setTDriftOffset()

◆ setUseSCDistortions() [1/3]

◆ setUseSCDistortions() [2/3]

◆ setUseSCDistortions() [3/3]

◆ setVDrift()