Describe astrophysical sources. More...

#include <Source.h>

Inheritance diagram for Source:

Collaboration diagram for Source:

Public Types
enum	sourcetype { type_photon , type_cosmic , type_photon_background }
	Enumerator to describe the type of astrophysical sources. More...

Public Member Functions
int	GenerateAstroParticles (const int aN, const ULong64_t aTime, const UInt_t aDuration)
	Generates N astro-particles from this source. More...

double	GetAstroEnergy (void)
	Returns the energy [keV] for the current astro-particle. More...

double	GetAstroPhip (void)
	Returns \(\varphi'\) for the current astro-particle. More...

double	GetAstroThetap (void)
	Returns \(\cos\theta'\) for the current astro-particle. More...

ULong64_t	GetAstroTime (void)
	Returns the time for the current astro-particle. More...

string	GetName (void)
	Returns the source name. More...

double	GetPhiPrime (const ULong64_t aTime)
	Returns the source \(\varphi'_{S}\) angle [rad] at a given time. More...

double	GetThetaPrime (const ULong64_t aTime)
	Returns the source \(\theta'_{S}\) angle [rad] at a given time. More...

int	GetType (void)
	Returns the source type. More...

void	SetName (const string aName)
	Sets the source name. More...

void	SetPosition (const double aThetaPrime, const double aPhiPrime, const double aConeAngle)
	Sets a fix source sky location. More...

void	SetType (const Source::sourcetype aType)
	Sets the source type. More...

int	TreeAstroGetN (void)
	Returns the number of particles currently in the astro-particle TTree. More...

int	TreeAstroLoadEntry (const int aEntryIndex)
	Loads a given entry in the astro-particle TTree. More...

void	TreeDelete (void)
	Deletes the TTree. More...

void	TreeInit (void)
	Initialize Source TTrees. More...

void	TreeReset (void)
	Resets baskets, buffers and entries count in all branches and leaves. More...

int	TreeWrite (void)
	Writes the source/astroparticles TTree to the current directory. More...

Constructors and destructors
	Source (const int aNt, const double aTimeMin, const double aTimeMax, const bool aUseTimeLog, const int aNe, const double aEnergyMin, const double aEnergyMax, const bool aUseEnergyLog)
	Source class constuctor. More...

	Source (TH2D aFlux, TH2D aRate=NULL)
	Source class constuctor. More...

virtual	~Source (void)
	Source class destructor. More...

Public Member Functions inherited from SpecTime
double	DrawEnergy (const double aTime)
	Draws an energy value at a given time. More...

TH2D *	GetFlux (void)
	Returns a pointer to the flux TH2D object. More...

TH1D *	GetLightCurve (const double aEnergyMin=0.0, const double aEnergyMax=-1.0)
	Returns the source light curve between two energies. More...

int	GetParticleN (const ULong64_t aTime, const UInt_t aDuration, const double aCosTheta=1.0)
	Computes the number of particles generated between 2 times. More...

TH2D *	GetRate (void)
	Returns a pointer to the flux TH2D object. More...

TH1D *	GetSpectrum (const double aTimeMin=0.0, const double aTimeMax=-1.0, const bool aObserved=false)
	Returns the source energy spectrum between two times. More...

double	GetTimeMax (void)
	Returns the maximum time defining the SpecTime object. More...

double	GetTimeMin (void)
	Returns the minimum time defining the SpecTime object. More...

void	MakeBandLimited (const double aFlux, const double aEnergyMin, const double aEnergyMax, TGraph *aSurface=NULL)
	Makes a band-limited flux SpecTime object. More...

void	MakeGRBData (TH1D aLightCurveExp, const double aE1, const double aE2, const double aPhotonIndex, const double aNint, const double aNgal, const double aZ, TGraph aSurfaceExp, TGraph *aSurface=NULL)
	Makes a SpecTime object using GRB data. More...

void	MakeGRBModel1 (const double aFlux, const double aEnergy0, const double aAlpha, const double aBeta, TGraph *aSurface=NULL)
	Makes a SpecTime object using a GRB model (I). More...

void	MakePowerLawEnergy (const double aFlux, const double aEnergyDecay, TGraph *aSurface=NULL)
	Makes a power-law flux SpecTime object. More...

void	MakePowerLawTime (const double aFlux, const double aTimeDecay, const double aEnergyMin, const double aEnergyMax, TGraph *aSurface=NULL)
	Makes a power-law flux SpecTime object. More...

void	MakeRate (TGraph *aSurface)
	Computes the rate given an integration surface. More...

void	MakeUniform (const double aFlux, TGraph *aSurface=NULL)
	Makes a uniform flux SpecTime object. More...

void	SetFlux (TH2D aFlux, TGraph aSurface=NULL)
	Defines a new flux fonction. More...

void	SetPhotoElectricCrossSection (TGraph *aGraph)
	Sets the photo-electric cross-section. More...

	SpecTime (const int aNt, const double aTimeBins, const int aNe, const double aEnergyBins)
	SpecTime class constuctor. More...

	SpecTime (const int aNt, const double aTimeMin, const double aTimeMax, const bool aUseTimeLog, const int aNe, const double aEnergyMin, const double aEnergyMax, const bool aUseEnergyLog)
	SpecTime class constuctor. More...

	SpecTime (TH2D aFlux, TH2D aRate=NULL)
	SpecTime class constuctor. More...

virtual	~SpecTime (void)
	SpecTime class destructor. More...

Private Member Functions
void	CommonConstructor (void)
	Common constructor. More...

void	ComputeR (void)
	Computes the rotation matrix to transform \(\vec{k'}\) in \(\vec{s}\). More...

Private Attributes
double	astro_energy
	astroparticle energy [keV]. More...

double	astro_phip
	astroparticle phi prime. More...

double	astro_thetap
	astroparticle \(\theta'\). More...

ULong64_t	astro_time
	astroparticle time [ms]. More...

TTree *	astro_tree
	astroparticle tree. More...

TGraph *	src_cosconeangle
	source cone angle [rad] as a function of time. More...

string	src_name
	source name. More...

TGraph *	src_phip
	source \(\varphi'_{S}\) as a function of time. More...

TGraph *	src_R [3][3]
	rotation matrix. More...

TGraph *	src_thetap
	source \(\theta'_{S}\) as a function of time. More...

TTree *	src_tree
	source parameter tree. More...

int	src_type
	source type, see Sources::sourcetype. More...

Additional Inherited Members
Protected Attributes inherited from SpecTime
TH2D *	flux
	source flux \({\cal{F}}(E,t)\). More...

TRandom3 *	randgen
	random generator. More...

TH2D *	rate
	source rate \({\cal{R}}(E,t)\). More...

Detailed Description

Describe astrophysical sources.

Description

An astrophysical source is described by a set of parameters:

a unique name (SetName())
a type: see Source::sourcetype (SetType())
a sky position, \(\theta'_S\), \(\varphi'_S\) (SetPosition()) given in spherical coordinates in the Earth celestial reference frame as represented below:

Source sky position. The Earth celestial reference frame is represented in black and the associated coordinates are primed.
a cone angle centered on the sky position (SetPosition()).

In addition, the particle emission is driven by the SpecTime class from which this class inherits.

Astro-particles

Once a source object is parameterized, this class can be used to generate astro-particles. Astro-particles are generated using a random generator. Each particle is given a set of parameters:

a time in \([\mathrm{ms}]\), \(t_p\).
a sky position given in spherical coordinates in the Earth celestial reference frame, \((\theta'_p,\varphi'_p)\).
an energy in \([\mathrm{keV}]\), \(E_p\).

Astro-particles are generated with GenerateAstroParticles(). The particle parameters are randomly drawn according to the source parameters. Refer to GenerateAstroParticles() to get a full description.

Time dependency

A source is a dynamical object, meaning that its parameters can change with time. The time validity of the source is defined in the constructor via the SpecTime object. After that, the time range of the SpecTime object can no longer be changed. One must make sure that this time range covers the entire experiment. The source does not exist outside the time range specified in the SpecTime object.

The time evolution of the source cannot be changed on the fly. It must be configured from the beginning with specific function:

Use the SpecTime configuration functions to configure the time dependency of the source flux.
Use SetPosition() to configure the time dependency of the source geometry (like the position and the extension).

Saving the source

After configuration, the source object as well as its astro-particles can be saved to disk in a ROOT file. After opening a TFile, the following functions should be called:

TreeInit(): intialize the TTrees:
- src_tree: source definition (one single entry)
- astro_tree: list of astro-particles
Generate particles with GenerateAstroParticles().
TreeWrite(): write the TTrees in the TFile.
TreeDelete(): delete TTrees.
Close the file.

See also: The SatAndLight file structure for source objects.

Author: Florent Robinet

Member Enumeration Documentation

◆ sourcetype

enum Source::sourcetype

Enumerator to describe the type of astrophysical sources.

Enumerator
type_photon	source of photons.
type_cosmic	source of cosmic rays.
type_photon_background	source of background photons.

Constructor & Destructor Documentation

◆ Source() [1/2]

Source::Source	(	const int	aNt,
		const double	aTimeMin,
		const double	aTimeMax,
		const bool	aUseTimeLog,
		const int	aNe,
		const double	aEnergyMin,
		const double	aEnergyMax,
		const bool	aUseEnergyLog
	)

Source class constuctor.

By default, the source object is given the following parameters:

name = "SRC"
type = photons
\(\theta'=0\) [rad] (fix value)
\(\varphi'=0\) [rad] (fix value)
cone angle = 0 [rad] (fix value)

See also: CommonConstructor().

The SpecTime object is also constructed to describe the particle emission. This is done using this constructor arguments: see SpecTime::SpecTime() for a description.

Parameters

[in]	aNt	Number of time bins.
[in]	aTimeMin	Minimum time \([\mathrm{ms}]\).
[in]	aTimeMax	Maximum time \([\mathrm{ms}]\).
[in]	aUseTimeLog	Flag to use logarithmic bins (true) or linear bins (false) for time.
[in]	aNe	Number of energy bins.
[in]	aEnergyMin	Minimum energy \([\mathrm{keV}]\).
[in]	aEnergyMax	Maximum energy \([\mathrm{keV}]\).
[in]	aUseEnergyLog	Flag to use logarithmic bins (true) or linear bins (false) for energy.

◆ Source() [2/2]

Source::Source	(	TH2D *	aFlux,
		TH2D *	aRate = `NULL`
	)

Source class constuctor.

By default, the source object is given the following parameters:

name = "SRC"
type = photons
\(\theta'=0\) [rad] (fix value)
\(\varphi'=0\) [rad] (fix value)
cone angle = 0 [rad] (fix value)

The SpecTime object is also constructed to describe the particle emission. This is done using this constructor arguments: see SpecTime::SpecTime() for a description.

Parameters

[in]	aFlux	Flux histogram.
[in]	aRate	Rate histogram. If a pointer to NULL is provided, a copy of the flux histogram is used.

◆ ~Source()

Source::~Source ( void )

virtual

Source class destructor.

Member Function Documentation

◆ CommonConstructor()

void Source::CommonConstructor ( void )

private

Common constructor.

◆ ComputeR()

void Source::ComputeR ( void )

private

Computes the rotation matrix to transform \(\vec{k'}\) in \(\vec{s}\).

\(\vec{k'}=(0,0,1)\) and \(\vec{s}=(\sin\theta'_S\cos\varphi'_S, \sin\theta'_S\sin\varphi'_S, \cos\theta'_S)\). The rotation axis is given by the unit vector \(\vec{n}=\frac{\vec{k'}\times\vec{s}}{||\vec{k'}\times\vec{s}||} = (-\sin\varphi'_S, \cos\varphi'_S, 0)\). The rotation matrix \(R\) is defined as the rotation by an angle \(\theta'_S\) about an axis in the direction of \(\vec{n}\) is:

\[ R= \left[ {\begin{array}{ccc} c_\theta+s^2_\varphi(1-c_\theta) & -s_\varphi c_\varphi(1-c_\theta) & s_\theta c_\varphi \\ -s_\varphi c_\varphi(1-c_\theta) & c_\theta+c^2_\varphi(1-c_\theta) & s_\theta s_\varphi \\ -s_\theta c_\varphi & -s_\theta s_\varphi & c_\theta \\ \end{array} } \right] \]

where \(c_\theta=\cos\theta'_S\) and \(s_\theta=\sin\theta'_S\) and the same for \(\varphi'_S\).

Note: The rotation matrix coefficients are functions of time.

◆ GenerateAstroParticles()

int Source::GenerateAstroParticles	(	const int	aN,
		const ULong64_t	aTime,
		const UInt_t	aDuration
	)

Generates N astro-particles from this source.

Once the source object is fully parameterized, you can generate astro-particles from this source with this function. The parameters of the particles are drawn randomly:

the particle time [ms] is drawn from a flat distribution in the given time range.
the particle energy is drawn following the source spectrum for this time [keV].
the particle sky location is randomly drawn in a cone centered on the source location \((\theta'_S, \varphi'_S)\). The algorithm to do that works in 2 steps:
- draw a position in a cone centered on the Earth north pole.
- perform a rotation to the source position using the rotation matrix defined in ComputeR().

Parameters

[in]	aN	Number of particles to generate.
[in]	aTime	Start time [ms].
[in]	aDuration	Time duration [ms].

Returns: The number of particles which are actually generated. This number can be smaller than the requested one if the requested time range does not match the source time range.

◆ GetAstroEnergy()

double Source::GetAstroEnergy ( void )

inline

Returns the energy [keV] for the current astro-particle.

The current astro-particle is the last particle generated with GenerateAstroParticles(). To load a previously-generated particle, TreeAstroLoadEntry() should be called first.

◆ GetAstroPhip()

double Source::GetAstroPhip ( void )

inline

Returns \(\varphi'\) for the current astro-particle.

The current astro-particle is the last particle generated with GenerateAstroParticles(). To load a previously-generated particle, TreeAstroLoadEntry() should be called first.

◆ GetAstroThetap()

double Source::GetAstroThetap ( void )

inline

Returns \(\cos\theta'\) for the current astro-particle.

The current astro-particle is the last particle generated with GenerateAstroParticles(). To load a previously-generated particle, TreeAstroLoadEntry() should be called first.

◆ GetAstroTime()

ULong64_t Source::GetAstroTime ( void )

inline

Returns the time for the current astro-particle.

The current astro-particle is the last particle generated with GenerateAstroParticles(). To load a previously-generated particle, TreeAstroLoadEntry() should be called first.

◆ GetName()

string Source::GetName ( void )

inline

Returns the source name.

◆ GetPhiPrime()

double Source::GetPhiPrime ( const ULong64_t aTime )

inline

Returns the source \(\varphi'_{S}\) angle [rad] at a given time.

Parameters

[in] aTime Time [ms].

Precondition: aTime must be a valid time in the range defined in the constructor.

◆ GetThetaPrime()

double Source::GetThetaPrime ( const ULong64_t aTime )

inline

Returns the source \(\theta'_{S}\) angle [rad] at a given time.

Parameters

[in] aTime Time [ms].

Precondition: aTime must be a valid time in the range defined in the constructor.

◆ GetType()

int Source::GetType ( void )

inline

Returns the source type.

◆ SetName()

void Source::SetName ( const string aName )

Sets the source name.

The source name must be unique if more than one source are used in the same time.

Parameters

[in] aName Source name.

◆ SetPosition()

void Source::SetPosition	(	const double	aThetaPrime,
		const double	aPhiPrime,
		const double	aConeAngle
	)

Sets a fix source sky location.

The source sky coordinates are set to a fix location: \(\theta'_S\) and \(\varphi'_S\). Moreover, the source can be given an extension centered on the source position and described by a spherical cap on the sphere. This is parameterized by a cone angle, defined from the cone axis. The astro-particles sky location is randomly drawn inside this cone.

The rotation matrix is also updated with the new parameter (see ComputeR()).

Parameters

[in]	aThetaPrime	\(\theta'_S\) in the Earth celestial reference frame [rad].
[in]	aPhiPrime	\(\varphi'_S\) in the Earth celestial reference frame [rad].
[in]	aConeAngle	Cone angle [rad], defined from the central position.

◆ SetType()

void Source::SetType ( const Source::sourcetype aType )

inline

Sets the source type.

See Source::sourcetype for a definition.

Parameters

[in] aType Source type.

◆ TreeAstroGetN()

int Source::TreeAstroGetN ( void )

inline

Returns the number of particles currently in the astro-particle TTree.

◆ TreeAstroLoadEntry()

int Source::TreeAstroLoadEntry ( const int aEntryIndex )

inline

Loads a given entry in the astro-particle TTree.

Returns: The number of bytes which are loaded. TBC.

Parameters

[in] aEntryIndex Astro-particle TTree index.

◆ TreeDelete()

void Source::TreeDelete ( void )

inline

Deletes the TTree.

Both the source and astro-particle trees are deleted.

◆ TreeInit()

void Source::TreeInit ( void )

Initialize Source TTrees.

Two TTrees are created: one to parameterize the source (one single entry) and one to save the astro-particles produced by the source.

The source TTree is named after the source and is given the following branches:

'src_type/I' = source type, see Sources::sourcetype.
'src_thetap/TGraph' = source \(\theta'_{S}\) as a function of time.
'src_phip/TGraph' = source \(\varphi'_{S}\) as a function of time.
'src_cosconeangle/TGraph' = source cone angle [rad] as a function of time.
'src_flux/TH2D' = source particle flux.
'src_rate/TH2D' = source particle rate.

The astro-particle tree is given the following branches:

'astro_time/l' = particle time.
'astro_thetap/D' = particle \(\theta'\).
'astro_phip/D' = particle \(\cos\varphi'\).
'astro_energy/D' = particle energy [keV].

◆ TreeReset()

void Source::TreeReset ( void )

inline

Resets baskets, buffers and entries count in all branches and leaves.

Calls the TTree Reset function.

◆ TreeWrite()

int Source::TreeWrite ( void )

inline

Writes the source/astroparticles TTree to the current directory.

Both the source and astro-particle trees are writtento disk. Calls the TTree Write function.

Returns: The total number of bytes written to the file. It returns 0 if the object cannot be written.

Todo:: Sort TTree indices to have particle sorted in time.

Member Data Documentation

◆ astro_energy

double Source::astro_energy

private

astroparticle energy [keV].

◆ astro_phip

double Source::astro_phip

private

astroparticle phi prime.

◆ astro_thetap

double Source::astro_thetap

private

astroparticle \(\theta'\).

◆ astro_time

ULong64_t Source::astro_time

private

astroparticle time [ms].

◆ astro_tree

TTree* Source::astro_tree

private

astroparticle tree.

◆ src_cosconeangle

TGraph* Source::src_cosconeangle

private

source cone angle [rad] as a function of time.

◆ src_name

string Source::src_name

private

source name.

◆ src_phip

TGraph* Source::src_phip

private

source \(\varphi'_{S}\) as a function of time.

◆ src_R

TGraph* Source::src_R[3][3]

private

rotation matrix.

◆ src_thetap

TGraph* Source::src_thetap

private

source \(\theta'_{S}\) as a function of time.

◆ src_tree

TTree* Source::src_tree

private

source parameter tree.

◆ src_type

int Source::src_type

private

source type, see Sources::sourcetype.

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

src/Source/Source.h
src/Source/Source.cc

Public Types

Public Member Functions

Private Member Functions

Private Attributes

Additional Inherited Members

Detailed Description

Description

Astro-particles

Time dependency

Saving the source

Member Enumeration Documentation

◆ sourcetype

Constructor & Destructor Documentation

◆ Source() [1/2]

◆ Source() [2/2]

◆ ~Source()

Member Function Documentation

◆ CommonConstructor()

◆ ComputeR()

◆ GenerateAstroParticles()

◆ GetAstroEnergy()

◆ GetAstroPhip()

◆ GetAstroThetap()

◆ GetAstroTime()

◆ GetName()

◆ GetPhiPrime()

◆ GetThetaPrime()

◆ GetType()

◆ SetName()

◆ SetPosition()

◆ SetType()

◆ TreeAstroGetN()

◆ TreeAstroLoadEntry()

◆ TreeDelete()

◆ TreeInit()

◆ TreeReset()

◆ TreeWrite()

Member Data Documentation

◆ astro_energy

◆ astro_phip

◆ astro_thetap

◆ astro_time

◆ astro_tree

◆ src_cosconeangle

◆ src_name

◆ src_phip

◆ src_R

◆ src_thetap

◆ src_tree

◆ src_type