Kernel for Nroi offest angle integration of diffuse model. More...

#include <GCTAResponse_helpers.hpp>

Inheritance diagram for cta_nroi_diffuse_kern_theta:

Public Member Functions
	cta_nroi_diffuse_kern_theta (const GCTAResponseIrf rsp, const GCTAObservation obs, const GModelSpatial model, const GMatrix rot, const GEnergy &srcEng, const GTime &srcTime, const GEnergy &obsEng, const GTime &obsTime, const int &iter)

double	eval (const double &theta)
	Kernel for Nroi offest angle integration of diffuse model. More...

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

	GFunction (const GFunction &function)
	Copy constructor. More...

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

GFunction &	operator= (const GFunction &function)
	Assignment operator. More...

Protected Attributes
const GCTAResponseIrf *	m_rsp
	CTA response. More...

const GCTAObservation *	m_obs
	CTA observation. More...

const GModelSpatial *	m_model
	Spatial model. More...

const GMatrix *	m_rot
	Rotation matrix. More...

GEnergy	m_srcEng
	True photon energy. More...

GTime	m_srcTime
	True photon arrival time. More...

GEnergy	m_obsEng
	Observed photon energy. More...

GTime	m_obsTime
	Observed photon arrival time. More...

int	m_iter
	Integration iterations. More...

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

void	copy_members (const GFunction &function)
	Copy class members. More...

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

Detailed Description

Kernel for Nroi offest angle integration of diffuse model.

This class implements the integration kernel \(K(\theta)\) for the integration

\[ \int_{0}^{\theta_{\rm max}} K(\theta | E, t) d\theta \]

of diffuse models. The eval() method computes

\[ K(\theta | E, t) = \sin \theta \times \int_{0}^{2\pi} S_{\rm p}(\theta, \phi | E, t) \, N_{\rm pred}(\theta, \phi) d\phi \]

where

\(S_{\rm p}(\theta, \phi | E, t)\) is the diffuse model,
\(N_{\rm pred}(\theta, \phi)\) is the data space integral of the Instrument Response Function for a point spread function over the Region Of Interest in the reference frame of the diffuse source model
\(\theta\) is the distance from the ROI centre, and
\(\phi\) is the azimuth angle.

Definition at line 932 of file GCTAResponse_helpers.hpp.

Constructor & Destructor Documentation

cta_nroi_diffuse_kern_theta::cta_nroi_diffuse_kern_theta	(	const GCTAResponseIrf *	rsp,
		const GCTAObservation *	obs,
		const GModelSpatial *	model,
		const GMatrix *	rot,
		const GEnergy &	srcEng,
		const GTime &	srcTime,
		const GEnergy &	obsEng,
		const GTime &	obsTime,
		const int &	iter
	)

inline

Definition at line 934 of file GCTAResponse_helpers.hpp.

Member Function Documentation

double cta_nroi_diffuse_kern_theta::eval ( const double & theta )

virtual

Kernel for Nroi offest angle integration of diffuse model.

Parameters

[in] theta Offset angle with respect to ROI centre (radians).

Computes

\[ K(\theta | E, t) = \sin \theta \times \int_{0}^{2\pi} S_{\rm p}(\theta, \phi | E, t) \, N_{\rm pred}(\theta, \phi) d\phi \]

This method integrates a diffuse model for a given offset angle with respect to the ROI centre over all azimuth angles (from 0 to 2pi). The integration is only performed for positive offset angles, otherwise 0 is returned.

Integration is done using the Romberg algorithm. The integration kernel is defined by the helper class cta_npred_diffuse_kern_phi.

Note that the integration precision was adjusted trading-off between computation time and computation precision. A value of 1e-4 was judged appropriate.

Implements GFunction.

Definition at line 1497 of file GCTAResponse_helpers.cpp.

References GIntegral::fixed_iter(), gammalib::is_infinite(), gammalib::is_notanumber(), m_iter, m_model, m_obs, m_obsEng, m_obsTime, m_rot, m_rsp, m_srcEng, m_srcTime, GIntegral::print(), gammalib::rad2deg, GIntegral::romberg(), sin(), and gammalib::twopi.

Member Data Documentation

int cta_nroi_diffuse_kern_theta::m_iter

protected

Integration iterations.

Definition at line 962 of file GCTAResponse_helpers.hpp.

Referenced by eval().

const GModelSpatial* cta_nroi_diffuse_kern_theta::m_model

protected

Spatial model.

Definition at line 956 of file GCTAResponse_helpers.hpp.

Referenced by eval().

const GCTAObservation* cta_nroi_diffuse_kern_theta::m_obs

protected

CTA observation.

Definition at line 955 of file GCTAResponse_helpers.hpp.

Referenced by eval().

GEnergy cta_nroi_diffuse_kern_theta::m_obsEng

protected

Observed photon energy.

Definition at line 960 of file GCTAResponse_helpers.hpp.

Referenced by eval().

GTime cta_nroi_diffuse_kern_theta::m_obsTime

protected

Observed photon arrival time.

Definition at line 961 of file GCTAResponse_helpers.hpp.

Referenced by eval().

const GMatrix* cta_nroi_diffuse_kern_theta::m_rot

protected

Rotation matrix.

Definition at line 957 of file GCTAResponse_helpers.hpp.

Referenced by eval().

const GCTAResponseIrf* cta_nroi_diffuse_kern_theta::m_rsp

protected

CTA response.

Definition at line 954 of file GCTAResponse_helpers.hpp.

Referenced by eval().

GEnergy cta_nroi_diffuse_kern_theta::m_srcEng

protected

True photon energy.

Definition at line 958 of file GCTAResponse_helpers.hpp.

Referenced by eval().

GTime cta_nroi_diffuse_kern_theta::m_srcTime

protected

True photon arrival time.

Definition at line 959 of file GCTAResponse_helpers.hpp.

Referenced by eval().

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

inst/cta/src/GCTAResponse_helpers.hpp
inst/cta/src/GCTAResponse_helpers.cpp

Public Member Functions

Protected Attributes

Additional Inherited Members

Detailed Description

Constructor & Destructor Documentation

Member Function Documentation

Member Data Documentation