CTA instrument response function class. More...

#include <GCTAResponseIrf.hpp>

Inheritance diagram for GCTAResponseIrf:

Public Member Functions
	GCTAResponseIrf (void)
	Void constructor. More...

	GCTAResponseIrf (const GCTAResponseIrf &rsp)
	Copy constructor. More...

	GCTAResponseIrf (const GXmlElement &xml)
	XML constructor. More...

	GCTAResponseIrf (const std::string &rspname, const GCaldb &caldb)
	Response constructor. More...

virtual	~GCTAResponseIrf (void)
	Destructor. More...

virtual GCTAResponseIrf &	operator= (const GCTAResponseIrf &rsp)
	Assignment operator. More...

virtual void	clear (void)
	Clear instance. More...

virtual GCTAResponseIrf *	clone (void) const
	Clone instance. More...

virtual std::string	classname (void) const
	Return class name. More...

virtual bool	is_valid (void) const
	Signal if response is valid. More...

virtual bool	use_edisp (void) const
	Signal if response uses energy dispersion. More...

virtual bool	use_tdisp (void) const
	Signal if time dispersion will be used. More...

virtual bool	apply_edisp (void) const
	Signal if energy dispersion should be applied. More...

virtual void	apply_edisp (const bool &apply_edisp) const
	Signal if energy dispersion should be applied. More...

virtual double	irf (const GEvent &event, const GPhoton &photon, const GObservation &obs) const
	Return value of instrument response function. More...

virtual double	nroi (const GModelSky &model, const GEnergy &obsEng, const GTime &obsTime, const GObservation &obs) const
	Return integral of event probability for a given sky model over ROI. More...

virtual GEbounds	ebounds (const GEnergy &obsEnergy) const
	Return true energy boundaries for a specific observed energy. More...

virtual void	read (const GXmlElement &xml)
	Read response from XML element. More...

virtual void	write (GXmlElement &xml) const
	Write response information into XML element. More...

virtual std::string	print (const GChatter &chatter=NORMAL) const
	Print CTA response information. More...

GCTAEventAtom *	mc (const double &area, const GPhoton &photon, const GObservation &obs, GRan &ran) const
	Simulate event from photon. More...

void	caldb (const GCaldb &caldb)
	Set calibration database. More...

const GCaldb &	caldb (void) const
	Return calibration database. More...

const std::string &	rspname (void) const
	Return response name. More...

void	load (const std::string &rspname)
	Load CTA response. More...

void	load_aeff (const GFilename &filename)
	Load effective area. More...

void	load_psf (const GFilename &filename)
	Load CTA PSF vector. More...

void	load_edisp (const GFilename &filename)
	Load energy dispersion information. More...

void	load_background (const GFilename &filename)
	Load background model. More...

void	offset_sigma (const double &sigma)
	Set offset angle dependence (degrees) More...

double	offset_sigma (void) const
	Return offset angle dependence (degrees) More...

const GCTAAeff *	aeff (void) const
	Return pointer to effective area response. More...

void	aeff (GCTAAeff *aeff)
	Set pointer to effective area response. More...

const GCTAPsf *	psf (void) const
	Return pointer to point spread function. More...

void	psf (GCTAPsf *psf)
	Set pointer to point spread function. More...

const GCTAEdisp *	edisp (void) const
	Return pointer to energy dispersion. More...

void	edisp (GCTAEdisp *edisp)
	Set pointer to energy dispersion. More...

const GCTABackground *	background (void) const
	Return pointer to background model. More...

void	background (GCTABackground *background)
	Set pointer to background model. More...

const double &	lo_safe_thres (void) const
	Return low energy threshold from IRF. More...

const double &	hi_safe_thres (void) const
	Return high energy threshold from IRF. More...

double	aeff (const double &theta, const double &phi, const double &zenith, const double &azimuth, const double &srcLogEng) const
	Return effective area (in units of cm2) More...

double	psf (const double &delta, const double &theta, const double &phi, const double &zenith, const double &azimuth, const double &srcLogEng) const
	Return point spread function (in units of sr^-1) More...

double	psf_delta_max (const double &theta, const double &phi, const double &zenith, const double &azimuth, const double &srcLogEng) const
	Return maximum angular separation (in radians) More...

double	edisp (const GEnergy &ereco, const GEnergy &etrue, const double &theta, const double &phi, const double &zenith, const double &azimuth) const
	Return energy dispersion (in units of MeV \(^{-1}\)) More...

double	nroi (const GModelSky &model, const GEnergy &srcEng, const GTime &srcTime, const GEnergy &obsEng, const GTime &obsTime, const GObservation &obs) const
	Return spatial integral of sky model. More...

double	nirf (const GPhoton &photon, const GEnergy &obsEng, const GTime &obsTime, const GObservation &obs) const
	Return spatial integral of Instrument Response Function. More...

double	npsf (const GSkyDir &srcDir, const double &srcLogEng, const GTime &srcTime, const GCTAPointing &pnt, const GCTARoi &roi) const
	Return result of PSF integration over ROI. More...

Public Member Functions inherited from GCTAResponse
	GCTAResponse (void)
	Void constructor. More...

	GCTAResponse (const GCTAResponse &rsp)
	Copy constructor. More...

virtual	~GCTAResponse (void)
	Destructor. More...

virtual GCTAResponse &	operator= (const GCTAResponse &rsp)
	Assignment operator. More...

Public Member Functions inherited from GResponse
	GResponse (void)
	Void constructor. More...

	GResponse (const GResponse &rsp)
	Copy constructor. More...

virtual	~GResponse (void)
	Destructor. More...

virtual GResponse &	operator= (const GResponse &rsp)
	Assignment operator. More...

virtual double	convolve (const GModelSky &model, const GEvent &event, const GObservation &obs, const bool &grad=true) const
	Convolve sky model with the instrument response. More...

virtual GVector	convolve (const GModelSky &model, const GObservation &obs, GMatrixSparse *gradients=NULL) const
	Convolve sky model with the instrument response. More...

virtual double	irf_spatial (const GEvent &event, const GSource &source, const GObservation &obs) const
	Return instrument response integrated over the spatial model. More...

virtual GVector	irf_spatial (const GModelSky &model, const GObservation &obs, GMatrix *gradients=NULL) const
	Return instrument response vector integrated over the spatial model. More...

virtual void	remove_response_cache (const std::string &name)
	Remove response cache for model. More...

Public Member Functions inherited from GBase
virtual	~GBase (void)
	Destructor. More...

Private Member Functions
void	init_members (void)
	Initialise class members. More...

void	copy_members (const GCTAResponseIrf &rsp)
	Copy class members. More...

void	free_members (void)
	Delete class members. More...

GFilename	irf_filename (const std::string &filename) const
	Return filename with appropriate extension. More...

double	irf_ptsrc (const GEvent &event, const GSource &source, const GObservation &obs) const
	Return value of point source instrument response function. More...

double	irf_radial (const GEvent &event, const GSource &source, const GObservation &obs) const
	Return IRF value for radial source model. More...

double	irf_elliptical (const GEvent &event, const GSource &source, const GObservation &obs) const
	Return Irf value for elliptical source model. More...

double	irf_diffuse (const GEvent &event, const GSource &source, const GObservation &obs) const
	Return value of diffuse source instrument response function. More...

double	nroi_ptsrc (const GModelSky &model, const GEnergy &srcEng, const GTime &srcTime, const GEnergy &obsEng, const GTime &obsTime, const GObservation &obs) const
	Return spatial integral of point source model. More...

double	nroi_radial (const GModelSky &model, const GEnergy &srcEng, const GTime &srcTime, const GEnergy &obsEng, const GTime &obsTime, const GObservation &obs) const
	Return spatial integral of radial source model. More...

double	nroi_elliptical (const GModelSky &model, const GEnergy &srcEng, const GTime &srcTime, const GEnergy &obsEng, const GTime &obsTime, const GObservation &obs) const
	Return spatial integral of elliptical source model. More...

double	nroi_diffuse (const GModelSky &model, const GEnergy &srcEng, const GTime &srcTime, const GEnergy &obsEng, const GTime &obsTime, const GObservation &obs) const
	Return spatial integral of diffuse source model. More...

double	nroi_composite (const GModelSky &model, const GEnergy &srcEng, const GTime &srcTime, const GEnergy &obsEng, const GTime &obsTime, const GObservation &obs) const
	Return spatial integral of composite source model. More...

Private Attributes
GCaldb	m_caldb
	Calibration database. More...

std::string	m_rspname
	Name of the instrument response. More...

GCTAAeff *	m_aeff
	Effective area. More...

GCTAPsf *	m_psf
	Point spread function. More...

GCTAEdisp *	m_edisp
	Energy dispersion. More...

GCTABackground *	m_background
	Background. More...

bool	m_apply_edisp
	Apply energy dispersion. More...

double	m_lo_safe_thres
	Safe low energy threshold. More...

double	m_hi_safe_thres
	Safe high energy threshold. More...

std::string	m_xml_caldb
	Calibration database string in XML file. More...

std::string	m_xml_rspname
	Response name in XML file. More...

Additional Inherited Members
Protected Member Functions inherited from GCTAResponse
void	init_members (void)
	Initialise class members. More...

void	copy_members (const GCTAResponse &rsp)
	Copy class members. More...

void	free_members (void)
	Delete class members. More...

Protected Member Functions inherited from GResponse
void	init_members (void)
	Initialise class members. More...

void	copy_members (const GResponse &rsp)
	Copy class members. More...

void	free_members (void)
	Delete class members. More...

double	eval_prob (const GModelSky &model, const GEvent &event, const GEnergy &srcEng, const GTime &srcTime, const GObservation &obs, const bool &grad) const
	Convolve sky model with the instrument response. More...

GVector	eval_probs (const GModelSky &model, const GObservation &obs, GMatrixSparse *gradients=NULL) const
	Convolve sky model with the instrument response. More...

int	size_edisp_vector (const GModelSky &model, const GObservation &obs, const bool &grad) const
	Return size of vector for energy dispersion computation. More...

GEbounds	ebounds_model (const GModelSky &model) const
	Return true energy intervals for sky model. More...

virtual double	irf_composite (const GEvent &event, const GSource &source, const GObservation &obs) const
	Return instrument response to composite source. More...

virtual GVector	irf_ptsrc (const GModelSky &model, const GObservation &obs, GMatrix *gradients=NULL) const
	Return instrument response to point source sky model. More...

virtual GVector	irf_radial (const GModelSky &model, const GObservation &obs, GMatrix *gradients=NULL) const
	Return instrument response to radial source sky model. More...

virtual GVector	irf_elliptical (const GModelSky &model, const GObservation &obs, GMatrix *gradients=NULL) const
	Return instrument response to ellipitical source sky model. More...

virtual GVector	irf_diffuse (const GModelSky &model, const GObservation &obs, GMatrix *gradients=NULL) const
	Return instrument response to diffuse source sky model. More...

virtual GVector	irf_composite (const GModelSky &model, const GObservation &obs, GMatrix *gradients=NULL) const
	Return instrument response to composite source sky model. More...

Protected Attributes inherited from GResponse
bool	m_use_irf_cache
	Control usage of irf cache. More...

bool	m_use_nroi_cache
	Control usage of nroi cache. More...

int	m_irf_radial_iter_theta
	Radial model integration theta iterations. More...

int	m_irf_radial_iter_phi
	Radial model integration phi iterations. More...

int	m_irf_elliptical_iter_theta
	Elliptical model integration theta iterations. More...

int	m_irf_elliptical_iter_phi
	Elliptical model integration phi iterations. More...

double	m_irf_diffuse_resolution
	Angular resolution for diffuse model. More...

GResponseCache	m_irf_cache

GResponseCache	m_nroi_cache

GResponseVectorCache	m_irf_vector_cache

Detailed Description

CTA instrument response function class.

Definition at line 62 of file GCTAResponseIrf.hpp.

Constructor & Destructor Documentation

GCTAResponseIrf::GCTAResponseIrf ( void )

Void constructor.

Constructs void CTA response.

Definition at line 140 of file GCTAResponseIrf.cpp.

References init_members().

Referenced by clone().

GCTAResponseIrf::GCTAResponseIrf ( const GCTAResponseIrf & rsp )

Copy constructor.

Parameters

[in] rsp CTA response.

Constructs CTA response by making a deep copy of an existing object.

Definition at line 157 of file GCTAResponseIrf.cpp.

References copy_members(), and init_members().

GCTAResponseIrf::GCTAResponseIrf ( const GXmlElement & xml )

explicit

XML constructor.

Parameters

[in] xml XML element.

Construct CTA response from XML element.

Definition at line 177 of file GCTAResponseIrf.cpp.

References init_members(), and read().

GCTAResponseIrf::GCTAResponseIrf	(	const std::string &	rspname,
		const GCaldb &	caldb
	)

Response constructor.

Parameters

[in]	rspname	Response file name.
[in]	caldb	Calibration database.

Create instance of CTA response by specifying the response name and the calibration database. The response name can be either a response identifier or a filename (see GCTAResponseIrf::load for more information).

Definition at line 200 of file GCTAResponseIrf.cpp.

References caldb(), init_members(), load(), and m_caldb.

GCTAResponseIrf::~GCTAResponseIrf ( void )

virtual

Destructor.

Destroys instance of CTA response object.

Definition at line 222 of file GCTAResponseIrf.cpp.

References free_members().

Member Function Documentation

const GCTAAeff * GCTAResponseIrf::aeff ( void ) const

inline

Return pointer to effective area response.

Returns: Pointer to effective area response.

Definition at line 349 of file GCTAResponseIrf.hpp.

References m_aeff.

Referenced by aeff(), GCTAOnOffObservation::arf_rad_max(), GCTAOnOffObservation::compute_arf_cut(), GCTAOnOffObservation::compute_rmf(), gammalib::cta_rsp_aeff(), cta_irf_radial_kern_omega::eval(), cta_irf_elliptical_kern_omega::eval(), cta_irf_diffuse_kern_phi::eval(), irf(), mc(), nirf(), read(), and write().

void GCTAResponseIrf::aeff ( GCTAAeff * aeff )

inline

Set pointer to effective area response.

Parameters

[in] aeff Pointer to effective area response.

Definition at line 361 of file GCTAResponseIrf.hpp.

References GCTAAeff::clone(), and m_aeff.

double GCTAResponseIrf::aeff	(	const double &	theta,
		const double &	phi,
		const double &	zenith,
		const double &	azimuth,
		const double &	srcLogEng
	)		const

Return effective area (in units of cm2)

Parameters

[in]	theta	Radial offset angle of photon in camera (radians).
[in]	phi	Polar angle of photon in camera (radians).
[in]	zenith	Zenith angle of telescope pointing (radians).
[in]	azimuth	Azimuth angle of telescope pointing (radians).
[in]	srcLogEng	Log10 of true photon energy (E/TeV).

Returns: Effective area in units fo cm2.

Exceptions

GException::invalid_value No effective area information found.

Returns the effective area as function of the true photon position in the camera system and the telescope pointing direction in the Earth system.

Definition at line 1736 of file GCTAResponseIrf.cpp.

References aeff(), G_AEFF, and m_aeff.

bool GCTAResponseIrf::apply_edisp ( void ) const

inlinevirtual

Signal if energy dispersion should be applied.

Returns: True if energy dispersion should be applied

Implements GCTAResponse.

Definition at line 274 of file GCTAResponseIrf.hpp.

References m_apply_edisp.

Referenced by apply_edisp(), GCTAOnOffObservation::compute_arf(), and print().

void GCTAResponseIrf::apply_edisp ( const bool & apply_edisp ) const

inlinevirtual

Signal if energy dispersion should be applied.

Parameters

[in] apply_edisp Set true if energy dispersion should be applied

Implements GCTAResponse.

Definition at line 285 of file GCTAResponseIrf.hpp.

References apply_edisp(), and m_apply_edisp.

const GCTABackground * GCTAResponseIrf::background ( void ) const

inline

Return pointer to background model.

Returns: Pointer to background model.

Definition at line 426 of file GCTAResponseIrf.hpp.

References m_background.

Referenced by gammalib::cta_rsp_bkg(), read(), and write().

void GCTAResponseIrf::background ( GCTABackground * background )

inline

Set pointer to background model.

Parameters

[in] background Pointer to background model.

Definition at line 438 of file GCTAResponseIrf.hpp.

References GCTABackground::clone(), and m_background.

void GCTAResponseIrf::caldb ( const GCaldb & caldb )

inline

Set calibration database.

Parameters

[in] caldb Calibration database.

Sets the calibration database for the CTA response.

Definition at line 324 of file GCTAResponseIrf.hpp.

References caldb(), and m_caldb.

Referenced by GCTAObservation::response(), and GCTAOnOffObservation::set().

const GCaldb & GCTAResponseIrf::caldb ( void ) const

inline

Return calibration database.

Returns: Calibration database.

Definition at line 310 of file GCTAResponseIrf.hpp.

References m_caldb.

Referenced by caldb(), GCTAResponseIrf(), load(), and read().

std::string GCTAResponseIrf::classname ( void ) const

inlinevirtual

Return class name.

Returns: String containing the class name ("GCTAResponseIrf").

Implements GCTAResponse.

Definition at line 234 of file GCTAResponseIrf.hpp.

void GCTAResponseIrf::clear ( void )

virtual

Clear instance.

Clears CTA response object by resetting all members to an initial state. Any information that was present in the object before will be lost.

Implements GCTAResponse.

Definition at line 285 of file GCTAResponseIrf.cpp.

References GCTAResponse::free_members(), GResponse::free_members(), free_members(), GCTAResponse::init_members(), GResponse::init_members(), and init_members().

Referenced by load().

GCTAResponseIrf * GCTAResponseIrf::clone ( void ) const

virtual

Clone instance.

Returns: Pointer to deep copy of CTA response.

Creates a clone (deep copy) of a CTA response object.

Implements GCTAResponse.

Definition at line 309 of file GCTAResponseIrf.cpp.

References GCTAResponseIrf().

void GCTAResponseIrf::copy_members ( const GCTAResponseIrf & rsp )

private

Copy class members.

Parameters

[in] rsp Response to be copied

Definition at line 2186 of file GCTAResponseIrf.cpp.

References GCTABackground::clone(), GCTAPsf::clone(), GCTAEdisp::clone(), GCTAAeff::clone(), m_aeff, m_apply_edisp, m_background, m_caldb, m_edisp, m_hi_safe_thres, m_lo_safe_thres, m_psf, m_rspname, m_xml_caldb, and m_xml_rspname.

Referenced by GCTAResponseIrf(), and operator=().

GEbounds GCTAResponseIrf::ebounds ( const GEnergy & obsEnergy ) const

virtual

Return true energy boundaries for a specific observed energy.

Parameters

[in] obsEnergy Observed Energy.

Returns: True energy boundaries for given observed energy.

Implements GCTAResponse.

Definition at line 525 of file GCTAResponseIrf.cpp.

References edisp(), and GCTAEdisp::etrue_bounds().

Referenced by nroi().

const GCTAEdisp * GCTAResponseIrf::edisp ( void ) const

inline

Return pointer to energy dispersion.

Returns: Pointer to energy dispersion.

Definition at line 399 of file GCTAResponseIrf.hpp.

References m_edisp.

Referenced by GCTAOnOffObservation::compute_rmf(), ebounds(), edisp(), cta_irf_radial_kern_omega::eval(), cta_irf_elliptical_kern_omega::eval(), cta_irf_diffuse_kern_phi::eval(), irf(), mc(), nirf(), nroi(), and write().

void GCTAResponseIrf::edisp ( GCTAEdisp * edisp )

inline

Set pointer to energy dispersion.

Parameters

[in] edisp Pointer to energy dispersion.

Definition at line 411 of file GCTAResponseIrf.hpp.

References GCTAEdisp::clone(), and m_edisp.

double GCTAResponseIrf::edisp	(	const GEnergy &	ereco,
		const GEnergy &	etrue,
		const double &	theta,
		const double &	phi,
		const double &	zenith,
		const double &	azimuth
	)		const

Return energy dispersion (in units of MeV \(^{-1}\))

Parameters

[in]	ereco	Reconstructed event energy.
[in]	etrue	True photon energy.
[in]	theta	Radial offset angle in camera (radians).
[in]	phi	Polar angle in camera (radians).
[in]	zenith	Zenith angle of telescope pointing (radians).
[in]	azimuth	Azimuth angle of telescope pointing (radians).

Returns: Energy dispersion (MeV \(^{-1}\)).

Definition at line 1851 of file GCTAResponseIrf.cpp.

References edisp().

void GCTAResponseIrf::free_members ( void )

private

Delete class members.

Definition at line 2215 of file GCTAResponseIrf.cpp.

References m_aeff, m_background, m_edisp, and m_psf.

Referenced by clear(), operator=(), and ~GCTAResponseIrf().

const double & GCTAResponseIrf::hi_safe_thres ( void ) const

inline

Return high energy threshold from IRF.

Returns: High energy threshold from IRF.

Definition at line 461 of file GCTAResponseIrf.hpp.

References m_hi_safe_thres.

void GCTAResponseIrf::init_members ( void )

private

Initialise class members.

< Switched off by default

Definition at line 2159 of file GCTAResponseIrf.cpp.

References GCaldb::clear(), m_aeff, m_apply_edisp, m_background, m_caldb, m_edisp, m_hi_safe_thres, m_lo_safe_thres, m_psf, m_rspname, m_xml_caldb, and m_xml_rspname.

Referenced by clear(), GCTAResponseIrf(), and operator=().

double GCTAResponseIrf::irf	(	const GEvent &	event,
		const GPhoton &	photon,
		const GObservation &	obs
	)		const

virtual

Return value of instrument response function.

Parameters

[in]	event	Observed event.
[in]	photon	Incident photon.
[in]	obs	Observation.

Todo:: Set polar angle phi of photon in camera system

Implements GCTAResponse.

Definition at line 324 of file GCTAResponseIrf.cpp.

References aeff(), GCTAPointing::azimuth(), gammalib::cta_dir(), gammalib::cta_pnt(), GObservation::deadc(), GPhoton::dir(), GCTAPointing::dir(), GCTAInstDir::dir(), GSkyDir::dist(), edisp(), GPhoton::energy(), G_IRF, gammalib::is_infinite(), gammalib::is_notanumber(), GEnergy::log10TeV(), psf(), psf_delta_max(), GPhoton::time(), use_edisp(), and GCTAPointing::zenith().

Referenced by irf_diffuse(), irf_elliptical(), irf_ptsrc(), and irf_radial().

double GCTAResponseIrf::irf_diffuse	(	const GEvent &	event,
		const GSource &	source,
		const GObservation &	obs
	)		const

privatevirtual

Return value of diffuse source instrument response function.

Parameters

[in]	event	Observed event.
[in]	source	Source.
[in]	obs	Observation.

Integrates the product of the model and the IRF over the true photon arrival direction using

\[ \int_{0}^{\theta_{\rm max}} \sin \theta \times PSF(\theta) \int_{0}^{2\pi} S_{\rm p}(\theta, \phi | E, t) \, Aeff(\theta, \phi) \, Edisp(\theta, \phi) d\phi \]

where

\(S_{\rm p}(\theta, \phi | E, t)\) is the diffuse model,
\(PSF(\theta)\) is the azimuthally symmetric Point Spread Function,
\(Aeff(\theta, \phi)\) is the effective area,
\(Edisp(\theta, \phi)\) is the energy dispersion,
\(\theta\) is the distance from the PSF centre, and
\(\phi\) is the azimuth angle.

The integration is performed in the reference of the observed arrival direction. Integration is done first over the azimuth angle \(\phi\) and then over the offset angle \(\theta\).

The integration kernels for this method are implemented by the response helper classes cta_irf_diffuse_kern_theta and cta_irf_diffuse_kern_phi.

Reimplemented from GResponse.

Definition at line 2764 of file GCTAResponseIrf.cpp.

References GCTAPointing::azimuth(), gammalib::cta_dir(), gammalib::cta_pnt(), GObservation::deadc(), GCTAPointing::dir(), GCTAInstDir::dir(), GSkyDir::dist(), GSource::energy(), GMatrix::eulery(), GMatrix::eulerz(), GIntegral::fixed_iter(), G_IRF_DIFFUSE, irf(), gammalib::is_infinite(), gammalib::is_notanumber(), gammalib::iter_rho(), GEnergy::log10TeV(), GSource::model(), psf_delta_max(), gammalib::resolution(), GIntegral::romberg(), GSource::time(), and GCTAPointing::zenith().

double GCTAResponseIrf::irf_elliptical	(	const GEvent &	event,
		const GSource &	source,
		const GObservation &	obs
	)		const

privatevirtual

Return Irf value for elliptical source model.

Parameters

[in]	event	Observed event.
[in]	source	Source.
[in]	obs	Observation.

Exceptions

GException::invalid_argument Model is not an elliptical model.

Integrates the product of the model and the IRF over the true photon arrival direction using

\[ \int_{\rho_{\rm min}}^{\rho_{\rm max}} \sin \rho \times \int_{\omega} S_{\rm p}(\rho, \omega | E, t) \, IRF(\rho, \omega) d\omega d\rho \]

where \(S_{\rm p}(\rho, \omega | E, t)\) is the elliptical model, \(IRF(\rho, \omega)\) is the instrument response function, \(\rho\) is the distance from the model centre, and \(\omega\) is the position angle with respect to the connecting line between the model centre and the observed photon arrival direction.

The source model centre is located at \(\vec{m}\), and a spherical coordinate system is defined around this location with \((\rho,\omega)\) being the zenith and azimuth angles, respectively. The azimuth angle \((\omega)\) is counted counterclockwise from the vector that runs from the model centre \(\vec{m}\) to the measured photon direction \(\vec{p'}\).

Reimplemented from GResponse.

Definition at line 2564 of file GCTAResponseIrf.cpp.

References GCTAPointing::azimuth(), gammalib::centre(), gammalib::cta_dir(), gammalib::cta_pnt(), GObservation::deadc(), gammalib::deg2rad, GCTAPointing::dir(), GCTAInstDir::dir(), GModelSpatialElliptical::dir(), GSkyDir::dist(), GSource::energy(), GIntegral::fixed_iter(), G_IRF_ELLIPTICAL, irf(), gammalib::is_infinite(), gammalib::is_notanumber(), gammalib::iter_phi(), gammalib::iter_rho(), GEnergy::log10TeV(), GSource::model(), gammalib::pihalf, GSkyDir::posang(), GModelSpatialElliptical::posangle(), psf_delta_max(), GIntegral::romberg(), GModelSpatialElliptical::semimajor(), GModelSpatialElliptical::semiminor(), GModelSpatialElliptical::theta_max(), GSource::time(), and GCTAPointing::zenith().

GFilename GCTAResponseIrf::irf_filename ( const std::string & filename ) const

private

Return filename with appropriate extension.

Parameters

[in] filename File name.

Returns: File name.

Checks if the specified filename exists, and if not, checks whether a file with the added suffix .dat exists. Returns the file name with the appropriate extension.

Definition at line 2244 of file GCTAResponseIrf.cpp.

References GFilename::exists().

Referenced by load().

double GCTAResponseIrf::irf_ptsrc	(	const GEvent &	event,
		const GSource &	source,
		const GObservation &	obs
	)		const

privatevirtual

Return value of point source instrument response function.

Parameters

[in]	event	Observed event.
[in]	source	Source.
[in]	obs	Observation.

Returns: Value of instrument response function for a point source.

This method returns the value of the instrument response function for a point source. The method assumes that source.model() is of type GModelSpatialPointSource.

Reimplemented from GResponse.

Definition at line 2274 of file GCTAResponseIrf.cpp.

References GModelSpatialPointSource::dir(), GSource::energy(), irf(), GSource::model(), and GSource::time().

double GCTAResponseIrf::irf_radial	(	const GEvent &	event,
		const GSource &	source,
		const GObservation &	obs
	)		const

privatevirtual

Return IRF value for radial source model.

Parameters

[in]	event	Observed event.
[in]	source	Source.
[in]	obs	Observation.

Exceptions

GException::invalid_argument Model is not a radial model.

Integrates the product of the spatial model and the instrument response function over the true photon arrival direction using

\[ \int_{\rho_{\rm min}}^{\rho_{\rm max}} \sin \rho \times S_{\rm p}(\rho | E, t) \times \int_{\omega_{\rm min}}^{\omega_{\rm max}} {\rm Irf}(\rho, \omega) d\omega d\rho \]

where \(S_{\rm p}(\rho | E, t)\) is the radial spatial model, \({\rm Irf}(\rho, \omega)\) is the instrument response function, \(\rho\) is the radial distance from the model centre, and \(\omega\) is the position angle with respect to the connecting line between the model centre and the observed photon arrival direction.

The integration is performed in the coordinate system of the source model spanned by \(\rho\) and \(\omega\) which allows to benefit from the symmetry of the source model.

The source centre is located at \(\vec{m}\), and a spherical system is defined around this location with \((\omega,\rho)\) being the azimuth and zenith angles, respectively. \(\omega=0\) is defined by the direction that connects the source centre \(\vec{m}\) to the measured photon direction \(\vec{p'}\), and \(\omega\) increases counterclockwise.

Note that this method approximates the true theta angle (angle between incident photon and pointing direction) by the measured theta angle (angle between the measured photon arrival direction and the pointing direction). Given the slow variation of the Psf shape over the field of view, this approximation should be fine. It helps in fact a lot in speeding up the computations.

Reimplemented from GResponse.

Definition at line 2338 of file GCTAResponseIrf.cpp.

References gammalib::acos(), GCTAPointing::azimuth(), gammalib::centre(), cos(), gammalib::cta_dir(), gammalib::cta_pnt(), GObservation::deadc(), gammalib::deg2rad, GCTAPointing::dir(), GCTAInstDir::dir(), GModelSpatialRadial::dir(), GSkyDir::dist(), GSource::energy(), GIntegral::fixed_iter(), G_IRF_RADIAL, irf(), gammalib::is_infinite(), gammalib::is_notanumber(), gammalib::iter_phi(), gammalib::iter_rho(), GEnergy::log10TeV(), GSource::model(), psf_delta_max(), gammalib::rad2deg, GModelSpatialRadialRing::radius(), GModelSpatialRadialShell::radius(), GIntegral::romberg(), sin(), GModelSpatialRadial::theta_max(), GSource::time(), and GCTAPointing::zenith().

bool GCTAResponseIrf::is_valid ( void ) const

inlinevirtual

Signal if response is valid.

Returns: True if response is valid

Implements GCTAResponse.

Definition at line 246 of file GCTAResponseIrf.hpp.

References m_aeff, and m_psf.

const double & GCTAResponseIrf::lo_safe_thres ( void ) const

inline

Return low energy threshold from IRF.

Returns: Low energy threshold from IRF.

Definition at line 450 of file GCTAResponseIrf.hpp.

References m_lo_safe_thres.

void GCTAResponseIrf::load ( const std::string & rspname )

Load CTA response.

Parameters

[in] rspname CTA response name.

Loads the CTA response with specified name rspname. The method first searchs for an appropriate response in the calibration database. If no appropriate response is found, the method takes the database root path and response name to build the full path to the response file, and tries to load the response from these paths.

The method sets the calibration database and response names for writing of the response information into the XML file.

Definition at line 1002 of file GCTAResponseIrf.cpp.

References caldb(), clear(), GCaldb::filename(), gammalib::filepath(), GCaldb::instrument(), irf_filename(), GFilename::is_empty(), load_aeff(), load_background(), load_edisp(), load_psf(), m_aeff, m_caldb, m_rspname, m_xml_caldb, m_xml_rspname, GCTAAeffArf::remove_thetacut(), GCaldb::rootdir(), and rspname().

Referenced by GCTAResponseIrf(), read(), and GCTAObservation::response().

void GCTAResponseIrf::load_aeff ( const GFilename & filename )

Load effective area.

Parameters

[in] filename Effective area filename.

Exceptions

GException::file_error File or extension not found.

Loads the effective area from a response file.

If the file is a FITS file, the method will either use the extension name specified with the filename, or if no extension name is given, search for an EFFECTIVE AREA or SPECRESP extension in the file and open the corresponding FITS table. If a column named SPECRESP is found in the table, a GCTAAeffArf object will be allocated. Otherwise, a GCTAAeff2D object will be allocated. In both cases, the method will extract the optional LO_THRES and HI_THRES safe energy thresholds from the FITS file header.

If the file is not a FITS file, it will be interpreted as a GCTAAeffPerfTable performance table.

Definition at line 1100 of file GCTAResponseIrf.cpp.

References GFits::close(), GFitsTable::contains(), GFits::contains(), GFilename::exists(), GFilename::extname(), gammalib::extname_arf, gammalib::extname_cta_aeff2d, G_LOAD_AEFF, gammalib::gadf_hduclas4(), GFitsHDU::has_card(), GFilename::has_extname(), GFilename::is_fits(), m_aeff, m_hi_safe_thres, m_lo_safe_thres, GFitsHDU::real(), and GFits::table().

Referenced by load(), and read().

void GCTAResponseIrf::load_background ( const GFilename & filename )

Load background model.

Parameters

[in] filename Background model file name.

Exceptions

GException::file_error File not found.

Loads the background model from a response file.

If the file is a FITS file the method will check whether the file contains a BKG_2D or BKG_3D table, and load correspondingly a GCTABackground2D or GCTABackground3D response.

If the file is not a FITS file it will be interpreted as a GCTABackgroundPerfTable performance table.

Definition at line 1472 of file GCTAResponseIrf.cpp.

References GFits::close(), GFitsTable::contains(), GFits::contains(), GFilename::exists(), GFilename::extname(), gammalib::extname_cta_background2d, gammalib::extname_cta_background3d, G_LOAD_BACKGROUND, GFilename::has_extname(), GFilename::is_fits(), m_background, and GFits::table().

Referenced by load(), and read().

void GCTAResponseIrf::load_edisp ( const GFilename & filename )

Load energy dispersion information.

Parameters

[in] filename Energy dispersion file name.

Exceptions

GException::file_error File or extension not found.

Loads the energy dispersion from a response file.

If the file is a FITS file, the method will either use the extension name specified with the filename, or if no extension name is given, search for an ENERGY DISPERSION or MATRIX extension in the file and open the corresponding FITS table. If columns named "MIGRA_LO" and "MIGRA_HI" are found in the table, a GCTAEdisp2D object will be allocated. Otherwise, a GCTAEdispRmf object will be allocated.

If the file is not a FITS file, it will be interpreted as a GCTAEdispPerfTable performance table.

Definition at line 1365 of file GCTAResponseIrf.cpp.

References GFits::close(), GFitsTable::contains(), GFits::contains(), GFilename::exists(), GFilename::extname(), gammalib::extname_cta_edisp2d, gammalib::extname_rmf, G_LOAD_EDISP, gammalib::gadf_hduclas4(), GFilename::has_extname(), GFilename::is_fits(), m_edisp, and GFits::table().

Referenced by load(), and read().

void GCTAResponseIrf::load_psf ( const GFilename & filename )

Load CTA PSF vector.

Parameters

[in] filename FITS file name.

Exceptions

GException::file_error File or extension not found.

Loads the point spead function from a response file.

If the file is a FITS file, the method will either use the extension name specified with the filename, or if no extension name is given, search for one of the following extension names

  POINT SPREAD FUNCTION
  PSF
  PSF_2D_TABLE

in the file and open the corresponding FITS table. If columns named GAMMA and SIGMA are found in the table, a GCTAPsfKing object will be allocated.

If columns named SCALE, SIGMA_1, AMPL_2, SIGMA_2, AMPL_3 and SIGMA_3 are found in the table, a GCTAPsf2D object will be allocated.

If columns named RAD_LO, RAD_HI, and RPSF are found in the table, a GCTAPsfTable object will be allocated.

Otherwise, a CTAPsfVector object will be allocated.

If the file is not a FITS file, it will be interpreted as a GCTAPsfPerfTable performance table.

Definition at line 1229 of file GCTAResponseIrf.cpp.

References GFits::close(), GFitsTable::contains(), GFits::contains(), GFilename::exists(), GFilename::extname(), G_LOAD_PSF, gammalib::gadf_hduclas4(), GFilename::has_extname(), GFilename::is_fits(), m_psf, and GFits::table().

Referenced by load(), and read().

GCTAEventAtom * GCTAResponseIrf::mc	(	const double &	area,
		const GPhoton &	photon,
		const GObservation &	obs,
		GRan &	ran
	)		const

Simulate event from photon.

Parameters

[in]	area	Simulation surface area.
[in]	photon	Photon.
[in]	obs	Observation.
[in]	ran	Random number generator.

Returns: Simulated event.

Simulates a CTA event using the response function from an incident photon. If the event is not detected a NULL pointer is returned.

The method also applies a deadtime correction using a Monte Carlo process, taking into account temporal deadtime variations. For this purpose, the method makes use of the time dependent GObservation::deadc method.

Todo:

Set polar angle phi of photon in camera system

Implement energy dispersion

Definition at line 559 of file GCTAResponseIrf.cpp.

References aeff(), GCTAPointing::azimuth(), gammalib::cta_pnt(), GObservation::deadc(), GCTAEventAtom::dir(), GPhoton::dir(), GCTAPointing::dir(), GSkyDir::dist(), edisp(), GPhoton::energy(), G_MC, GCTAPointing::instdir(), GEnergy::log10TeV(), GCTAPsf::mc(), GCTAEdisp::mc(), psf(), gammalib::rad2deg, GSkyDir::rotate_deg(), gammalib::str(), GEnergy::TeV(), GPhoton::time(), GRan::uniform(), use_edisp(), gammalib::warning(), and GCTAPointing::zenith().

double GCTAResponseIrf::nirf	(	const GPhoton &	photon,
		const GEnergy &	obsEng,
		const GTime &	obsTime,
		const GObservation &	obs
	)		const

Return spatial integral of Instrument Response Function.

Parameters

[in]	photon	Photon.
[in]	obsEng	Observed event energy.
[in]	obsTime	Observed event time.
[in]	obs	Observation.

Computes the integral of the instrument response function over the Region of Interest

\[ R(E',t'|p,E,t) = \int_{\rm ROI} R(p',E',t'|p,E,t) dp' \]

Definition at line 1964 of file GCTAResponseIrf.cpp.

References aeff(), GCTAPointing::azimuth(), gammalib::cta_event_list(), gammalib::cta_obs(), GObservation::deadc(), GPhoton::dir(), GCTAPointing::dir(), GSkyDir::dist(), edisp(), GPhoton::energy(), G_NIRF, gammalib::is_infinite(), gammalib::is_notanumber(), GEnergy::log10TeV(), npsf(), nroi(), GCTAObservation::pointing(), GCTAEventList::roi(), GPhoton::time(), use_edisp(), and GCTAPointing::zenith().

Referenced by cta_nroi_radial_kern_omega::eval(), cta_nroi_elliptical_kern_omega::eval(), cta_nroi_diffuse_kern_phi::eval(), and nroi_ptsrc().

double GCTAResponseIrf::npsf	(	const GSkyDir &	srcDir,
		const double &	srcLogEng,
		const GTime &	srcTime,
		const GCTAPointing &	pnt,
		const GCTARoi &	roi
	)		const

Return result of PSF integration over ROI.

Parameters

[in]	srcDir	True photon direction.
[in]	srcLogEng	Log10 of true photon energy (E/TeV).
[in]	srcTime	True photon arrival time (not used).
[in]	pnt	CTA pointing.
[in]	roi	CTA region of interest.

This method integrates the PSF over the circular region of interest (ROI). Integration is done in a polar coordinate system centred on the PSF since the PSF is assumed to be azimuthally symmetric. The polar integration is done using the method npsf_kern_rad_azsym() that computes analytically the arclength that is comprised within the ROI.

Note that the integration is only performed when the PSF is spilling out of the ROI border, otherwise the integral is simply 1. Numerical integration is done using the standard Romberg method. The integration boundaries are computed so that only the PSF section that falls in the ROI is considered.

Todo:

Enhance romberg() integration method for small integration regions (see comment about kluge below)

Implement phi dependence in camera system

Definition at line 2054 of file GCTAResponseIrf.cpp.

References GCTAPointing::azimuth(), GCTARoi::centre(), gammalib::deg2rad, GCTAPointing::dir(), GCTAInstDir::dir(), GSkyDir::dist(), GIntegral::fixed_iter(), gammalib::is_infinite(), gammalib::is_notanumber(), psf_delta_max(), gammalib::rad2deg, GCTARoi::radius(), GIntegral::romberg(), GIntegral::trapzd(), and GCTAPointing::zenith().

Referenced by nirf().

double GCTAResponseIrf::nroi	(	const GModelSky &	model,
		const GEnergy &	obsEng,
		const GTime &	obsTime,
		const GObservation &	obs
	)		const

virtual

Return integral of event probability for a given sky model over ROI.

Parameters

[in]	model	Sky model.
[in]	obsEng	Observed photon energy.
[in]	obsTime	Observed photon arrival time.
[in]	obs	Observation.

Returns: Event probability.

Exceptions

GException::feature_not_implemented Method is not implemented.

Computes the integral

\[ N_{\rm ROI}(E',t') = \int_{\rm ROI} P(p',E',t') dp' \]

of the event probability

\[ P(p',E',t') = \int \int \int S(p,E,t) \times R(p',E',t'|p,E,t) \, dp \, dE \, dt \]

for a given sky model \(S(p,E,t)\) and response function \(R(p',E',t'|p,E,t)\) over the Region of Interest (ROI).

Implements GCTAResponse.

Definition at line 434 of file GCTAResponseIrf.cpp.

References ebounds(), edisp(), GEbounds::emax(), GEbounds::emin(), GCTAEdisp::etrue_bounds(), GModelTemporal::eval(), GModelSpectral::eval(), GIntegral::fixed_iter(), GModel::has_scales(), GObservation::instrument(), gammalib::is_infinite(), gammalib::is_notanumber(), GEnergy::MeV(), GIntegral::romberg(), GModel::scale(), GEbounds::size(), GModelSky::spectral(), GModelSky::temporal(), and use_edisp().

Referenced by cta_nroi_kern::eval(), nirf(), nroi(), nroi_composite(), nroi_diffuse(), nroi_elliptical(), nroi_ptsrc(), and nroi_radial().

double GCTAResponseIrf::nroi	(	const GModelSky &	model,
		const GEnergy &	srcEng,
		const GTime &	srcTime,
		const GEnergy &	obsEng,
		const GTime &	obsTime,
		const GObservation &	obs
	)		const

Return spatial integral of sky model.

Parameters

[in]	model	Sky Model.
[in]	srcEng	True photon energy.
[in]	srcTime	True photon arrival time.
[in]	obsEng	Observed event energy.
[in]	obsTime	Observed event arrival time.
[in]	obs	Observation.

Computes the integral

\[ N_{\rm ROI}(E',t'|E,t) = \int_{\rm ROI} P(p',E',t'|E,t) dp' \]

of

\[ P(p',E',t'|E,t) = \int S(p,E,t) \times R(p',E',t'|p,E,t) \, dp \]

over the Region of Interest (ROI) for a sky model \(S(p,E,t)\) and the response function \(R(p',E',t'|p,E,t)\).

Definition at line 1892 of file GCTAResponseIrf.cpp.

References GModelSpatial::code(), GResponseCache::contains(), GMODEL_SPATIAL_COMPOSITE, GMODEL_SPATIAL_DIFFUSE, GMODEL_SPATIAL_ELLIPTICAL, GMODEL_SPATIAL_POINT_SOURCE, GMODEL_SPATIAL_RADIAL, GModelSpatial::has_free_pars(), GObservation::id(), GResponse::m_nroi_cache, GResponse::m_use_nroi_cache, GModel::name(), nroi(), nroi_composite(), nroi_diffuse(), nroi_elliptical(), nroi_ptsrc(), nroi_radial(), GResponseCache::set(), and GModelSky::spatial().

double GCTAResponseIrf::nroi_composite	(	const GModelSky &	model,
		const GEnergy &	srcEng,
		const GTime &	srcTime,
		const GEnergy &	obsEng,
		const GTime &	obsTime,
		const GObservation &	obs
	)		const

private

Return spatial integral of composite source model.

Parameters

[in]	model	Sky Model.
[in]	srcEng	True photon energy.
[in]	srcTime	True photon arrival time.
[in]	obsEng	Observed event energy.
[in]	obsTime	Observed event arrival time.
[in]	obs	Observation.

Computes the integral

\[ N_{\rm ROI}(E',t'|E,t) = \int_{\rm ROI} P(p',E',t'|E,t) dp' \]

of

\[ P(p',E',t'|E,t) = \int S(p,E,t) \times R(p',E',t'|p,E,t) \, dp \]

over the Region of Interest (ROI) for a composite source model \(S(p,E,t)\) and the response function \(R(p',E',t'|p,E,t)\).

Definition at line 3511 of file GCTAResponseIrf.cpp.

References GModelSpatialComposite::component(), GModelSpatialComposite::components(), nroi(), GModelSpatialComposite::scale(), GModelSky::spatial(), sum(), and GModelSpatialComposite::sum_of_scales().

Referenced by nroi().

double GCTAResponseIrf::nroi_diffuse	(	const GModelSky &	model,
		const GEnergy &	srcEng,
		const GTime &	srcTime,
		const GEnergy &	obsEng,
		const GTime &	obsTime,
		const GObservation &	obs
	)		const

private

Return spatial integral of diffuse source model.

Parameters

[in]	model	Sky Model.
[in]	srcEng	True photon energy.
[in]	srcTime	True photon arrival time.
[in]	obsEng	Observed event energy.
[in]	obsTime	Observed event arrival time.
[in]	obs	Observation.

Returns: Spatial integral of diffuse source model.

Exceptions

GException::invalid_argument Invalid spatial model specified.

Computes the integral

\[ N_{\rm ROI}(E',t'|E,t) = \int_{\rm ROI} P(p',E',t'|E,t) dp' \]

of

\[ P(p',E',t'|E,t) = \int S(p,E,t) \times R(p',E',t'|p,E,t) \, dp \]

over the Region of Interest (ROI) for a diffuse source model \(S(p,E,t)\) and the response function \(R(p',E',t'|p,E,t)\).

Definition at line 3376 of file GCTAResponseIrf.cpp.

References GCTAPointing::azimuth(), GCTARoi::centre(), gammalib::cta_event_list(), gammalib::cta_obs(), gammalib::deg2rad, GCTAInstDir::dir(), GMatrix::eulery(), GMatrix::eulerz(), GIntegral::fixed_iter(), G_NROI_DIFFUSE, gammalib::is_infinite(), gammalib::is_notanumber(), gammalib::iter_phi(), gammalib::iter_rho(), GEnergy::log10TeV(), nroi(), GCTAObservation::pointing(), psf_delta_max(), GCTARoi::radius(), GCTAEventList::roi(), GIntegral::romberg(), GModelSky::spatial(), and GCTAPointing::zenith().

Referenced by nroi().

double GCTAResponseIrf::nroi_elliptical	(	const GModelSky &	model,
		const GEnergy &	srcEng,
		const GTime &	srcTime,
		const GEnergy &	obsEng,
		const GTime &	obsTime,
		const GObservation &	obs
	)		const

private

Return spatial integral of elliptical source model.

Parameters

[in]	model	Sky Model.
[in]	srcEng	True photon energy.
[in]	srcTime	True photon arrival time.
[in]	obsEng	Observed event energy.
[in]	obsTime	Observed event arrival time.
[in]	obs	Observation.

Returns: Spatial integral of elliptical source model.

Exceptions

GException::invalid_argument Invalid spatial model specified.

Computes the integral

\[ N_{\rm ROI}(E',t'|E,t) = \int_{\rm ROI} P(p',E',t'|E,t) dp' \]

of

\[ P(p',E',t'|E,t) = \int S(p,E,t) \times R(p',E',t'|p,E,t) \, dp \]

over the Region of Interest (ROI) for an elliptical source model \(S(p,E,t)\) and the response function \(R(p',E',t'|p,E,t)\).

Definition at line 3181 of file GCTAResponseIrf.cpp.

References GCTAPointing::azimuth(), GCTARoi::centre(), gammalib::centre(), gammalib::cta_event_list(), gammalib::cta_obs(), GSkyDir::dec_deg(), gammalib::deg2rad, GCTAInstDir::dir(), GModelSpatialElliptical::dir(), GMatrix::eulery(), GMatrix::eulerz(), GIntegral::fixed_iter(), G_NROI_ELLIPTICAL, gammalib::is_infinite(), gammalib::is_notanumber(), gammalib::iter_phi(), gammalib::iter_rho(), GEnergy::log10TeV(), nroi(), gammalib::pihalf, GCTAObservation::pointing(), GSkyDir::posang(), GModelSpatialElliptical::posangle(), psf_delta_max(), GSkyDir::ra_deg(), GCTARoi::radius(), GCTAEventList::roi(), GIntegral::romberg(), GModelSpatialElliptical::semimajor(), GModelSpatialElliptical::semiminor(), GModelSky::spatial(), GModelSpatialElliptical::theta_max(), and GCTAPointing::zenith().

Referenced by nroi().

double GCTAResponseIrf::nroi_ptsrc	(	const GModelSky &	model,
		const GEnergy &	srcEng,
		const GTime &	srcTime,
		const GEnergy &	obsEng,
		const GTime &	obsTime,
		const GObservation &	obs
	)		const

private

Return spatial integral of point source model.

Parameters

[in]	model	Sky Model.
[in]	srcEng	True photon energy.
[in]	srcTime	True photon arrival time.
[in]	obsEng	Observed event energy.
[in]	obsTime	Observed event arrival time.
[in]	obs	Observation.

Computes the integral

\[ N_{\rm ROI}(E',t'|E,t) = \int_{\rm ROI} P(p',E',t'|E,t) dp' \]

of

\[ P(p',E',t'|E,t) = \int S(p,E,t) \times R(p',E',t'|p,E,t) \, dp \]

over the Region of Interest (ROI) for a point source model \(S(p,E,t)\) and the response function \(R(p',E',t'|p,E,t)\).

Definition at line 2926 of file GCTAResponseIrf.cpp.

References GModelSpatialPointSource::dir(), nirf(), nroi(), and GModelSky::spatial().

Referenced by nroi().

double GCTAResponseIrf::nroi_radial	(	const GModelSky &	model,
		const GEnergy &	srcEng,
		const GTime &	srcTime,
		const GEnergy &	obsEng,
		const GTime &	obsTime,
		const GObservation &	obs
	)		const

private

Return spatial integral of radial source model.

Parameters

[in]	model	Sky Model.
[in]	srcEng	True photon energy.
[in]	srcTime	True photon arrival time.
[in]	obsEng	Observed event energy.
[in]	obsTime	Observed event arrival time.
[in]	obs	Observation.

Returns: Spatial integral of radial source model.

Exceptions

GException::invalid_argument Invalid spatial model specified.

Computes the integral

\[ N_{\rm ROI}(E',t'|E,t) = \int_{\rm ROI} P(p',E',t'|E,t) dp' \]

of

\[ P(p',E',t'|E,t) = \int S(p,E,t) \times R(p',E',t'|p,E,t) \, dp \]

over the Region of Interest (ROI) for a radial source model \(S(p,E,t)\) and the response function \(R(p',E',t'|p,E,t)\).

Definition at line 2978 of file GCTAResponseIrf.cpp.

References GCTAPointing::azimuth(), GCTARoi::centre(), gammalib::centre(), gammalib::cta_event_list(), gammalib::cta_obs(), GSkyDir::dec_deg(), gammalib::deg2rad, GCTAInstDir::dir(), GModelSpatialRadial::dir(), GMatrix::eulery(), GMatrix::eulerz(), GIntegral::fixed_iter(), G_NROI_RADIAL, gammalib::is_infinite(), gammalib::is_notanumber(), gammalib::iter_phi(), gammalib::iter_rho(), GEnergy::log10TeV(), nroi(), GCTAObservation::pointing(), GSkyDir::posang(), psf_delta_max(), GSkyDir::ra_deg(), GCTARoi::radius(), GModelSpatialRadialRing::radius(), GModelSpatialRadialShell::radius(), GCTAEventList::roi(), GIntegral::romberg(), GModelSky::spatial(), GModelSpatialRadial::theta_max(), and GCTAPointing::zenith().

Referenced by nroi().

void GCTAResponseIrf::offset_sigma ( const double & sigma )

Set offset angle dependence (degrees)

Parameters

[in] sigma Offset angle dependence value (degrees).

Set the offset angle dependence for 1D effective area functions. The method set the sigma value in case that the effective area function is of type GCTAAeffArf or GCTAAeffPerfTable. Otherwise, nothing will be done.

Definition at line 1565 of file GCTAResponseIrf.cpp.

References m_aeff, GCTAAeffPerfTable::sigma(), and GCTAAeffArf::sigma().

double GCTAResponseIrf::offset_sigma ( void ) const

Return offset angle dependence (degrees)

Returns: Offset angle dependence value (degrees).

Return the offset angle dependence for 1D effective area functions. The method returns the sigma value in case that the effective area function is of type GCTAAeffArf or GCTAAeffPerfTable. Otherwise, 0.0 will be returned.

Definition at line 1594 of file GCTAResponseIrf.cpp.

References m_aeff, GCTAAeffPerfTable::sigma(), and GCTAAeffArf::sigma().

GCTAResponseIrf & GCTAResponseIrf::operator= ( const GCTAResponseIrf & rsp )

virtual

Assignment operator.

Parameters

[in] rsp CTA response.

Returns: CTA response.

Assigns CTA response object to another CTA response object. The assignment performs a deep copy of all information, hence the original object from which the assignment has been performed can be destroyed after this operation without any loss of information.

Definition at line 249 of file GCTAResponseIrf.cpp.

References copy_members(), free_members(), init_members(), and GCTAResponse::operator=().

std::string GCTAResponseIrf::print ( const GChatter & chatter = NORMAL ) const

virtual

Print CTA response information.

Parameters

[in] chatter Chattiness.

Returns: String containing CTA response information.

Implements GCTAResponse.

Definition at line 1622 of file GCTAResponseIrf.cpp.

References apply_edisp(), GCaldb::instrument(), m_aeff, m_background, m_caldb, m_edisp, m_hi_safe_thres, GResponse::m_irf_cache, m_lo_safe_thres, GResponse::m_nroi_cache, m_psf, m_rspname, GCaldb::mission(), NORMAL, gammalib::parformat(), GCTABackground::print(), GCTAAeff::print(), GCTAPsf::print(), GCTAEdisp::print(), GResponseCache::print(), GCaldb::print(), gammalib::reduce(), SILENT, gammalib::str(), and use_edisp().

const GCTAPsf * GCTAResponseIrf::psf ( void ) const

inline

Return pointer to point spread function.

Returns: Pointer to point spread function.

Definition at line 374 of file GCTAResponseIrf.hpp.

References m_psf.

Referenced by cta_npsf_kern_rad_azsym::eval(), cta_irf_radial_kern_omega::eval(), cta_irf_elliptical_kern_omega::eval(), cta_irf_diffuse_kern_theta::eval(), irf(), mc(), psf(), and write().

void GCTAResponseIrf::psf ( GCTAPsf * psf )

inline

Set pointer to point spread function.

Parameters

[in] psf Pointer to point spread function.

Definition at line 386 of file GCTAResponseIrf.hpp.

References GCTAPsf::clone(), and m_psf.

double GCTAResponseIrf::psf	(	const double &	delta,
		const double &	theta,
		const double &	phi,
		const double &	zenith,
		const double &	azimuth,
		const double &	srcLogEng
	)		const

Return point spread function (in units of sr^-1)

Parameters

[in]	delta	Angular separation between true and measured photon directions (radians).
[in]	theta	Radial offset angle of photon in camera (radians).
[in]	phi	Polar angle of photon in camera (radians).
[in]	zenith	Zenith angle of telescope pointing (radians).
[in]	azimuth	Azimuth angle of telescope pointing (radians).
[in]	srcLogEng	Log10 of true photon energy (E/TeV).

Exceptions

GException::invalid_value No point spread function information found.

Returns the point spread function for a given offset angle as function of the true photon position in the camera system and the telescope pointing direction in the Earth system.

Definition at line 1776 of file GCTAResponseIrf.cpp.

References G_PSF, m_psf, and psf().

double GCTAResponseIrf::psf_delta_max	(	const double &	theta,
		const double &	phi,
		const double &	zenith,
		const double &	azimuth,
		const double &	srcLogEng
	)		const

Return maximum angular separation (in radians)

Parameters

[in]	theta	Radial offset angle in camera (radians).
[in]	phi	Polar angle in camera (radians).
[in]	zenith	Zenith angle of telescope pointing (radians).
[in]	azimuth	Azimuth angle of telescope pointing (radians).
[in]	srcLogEng	Log10 of true photon energy (E/TeV).

Exceptions

GException::invalid_value No point spread function information found.

This method returns the maximum angular separation between true and measured photon directions for which the PSF is non zero as function of the true photon position in the camera system and the telescope pointing direction in the Earth system.

Definition at line 1817 of file GCTAResponseIrf.cpp.

References GCTAPsf::delta_max(), G_PSF_DELTA_MAX, and m_psf.

Referenced by irf(), irf_diffuse(), irf_elliptical(), irf_radial(), npsf(), nroi_diffuse(), nroi_elliptical(), and nroi_radial().

void GCTAResponseIrf::read ( const GXmlElement & xml )

virtual

Read response from XML element.

Parameters

[in] xml XML element.

Reads information for a CTA observation from an XML element. The calibration database and response name can be specified using

<observation name="..." id="..." instrument="...">
  ...
  <parameter name="Calibration" database="..." response="..."/>
</observation>

If even more control is required over the response, individual file names can be specified using

<observation name="..." id="..." instrument="...">
  ...
  <parameter name="EffectiveArea"       file="..."/>
  <parameter name="PointSpreadFunction" file="..."/>
  <parameter name="EnergyDispersion"    file="..."/>
  <parameter name="Background"          file="..."/>
</observation>

Implements GCTAResponse.

Definition at line 675 of file GCTAResponseIrf.cpp.

References aeff(), GXmlElement::attribute(), background(), caldb(), G_READ, GXmlElement::has_attribute(), load(), load_aeff(), load_background(), load_edisp(), load_psf(), GCTAAeffArf::remove_thetacut(), GCTAAeffArf::scale(), GCTAAeffPerfTable::sigma(), GCTABackgroundPerfTable::sigma(), GCTAAeffArf::sigma(), gammalib::strip_whitespace(), GCTAAeffArf::thetacut(), gammalib::todouble(), gammalib::tolower(), gammalib::xml_get_par(), and gammalib::xml_has_par().

Referenced by GCTAResponseIrf().

const std::string & GCTAResponseIrf::rspname ( void ) const

inline

Return response name.

Returns: Response name.

Definition at line 337 of file GCTAResponseIrf.hpp.

References m_rspname.

Referenced by load(), and GCTAOnOffObservation::set().

bool GCTAResponseIrf::use_edisp ( void ) const

inlinevirtual

Signal if response uses energy dispersion.

Returns: True if response uses energy dispersion

Signals if the response uses energy dispersion. This implies that the apply_edisp flag has been set to true and that energy dispersion response information is available.

Implements GCTAResponse.

Definition at line 262 of file GCTAResponseIrf.hpp.

References m_apply_edisp, and m_edisp.

Referenced by cta_irf_radial_kern_omega::eval(), cta_irf_elliptical_kern_omega::eval(), cta_irf_diffuse_kern_phi::eval(), irf(), mc(), nirf(), nroi(), and print().

bool GCTAResponseIrf::use_tdisp ( void ) const

inlinevirtual

Signal if time dispersion will be used.

Returns: False.

Implements GCTAResponse.

Definition at line 298 of file GCTAResponseIrf.hpp.

void GCTAResponseIrf::write ( GXmlElement & xml ) const

virtual

Write response information into XML element.

Parameters

[in] xml XML element.

Writes information for a CTA response into an XML element. If the calibration database and response name had been specified, the following output is written

<observation name="..." id="..." instrument="...">
  ...
  <parameter name="Calibration" database="..." response="..."/>
</observation>

If even more control was required over the response and individual file names were specified, the following output is written

<observation name="..." id="..." instrument="...">
  ...
  <parameter name="EffectiveArea"       file="..."/>
  <parameter name="PointSpreadFunction" file="..."/>
  <parameter name="EnergyDispersion"    file="..."/>
  <parameter name="Background"          file="..."/>
</observation>

Implements GCTAResponse.

Definition at line 889 of file GCTAResponseIrf.cpp.

References aeff(), GXmlElement::attribute(), background(), edisp(), GCTAAeff::filename(), G_WRITE, GFilename::is_empty(), m_xml_caldb, m_xml_rspname, psf(), GCTAAeffArf::scale(), GCTAAeffPerfTable::sigma(), GCTAAeffArf::sigma(), gammalib::str(), GCTAAeffArf::thetacut(), and gammalib::xml_need_par().