Kernel for Nroi offest angle integration of diffuse model. More...
#include <GCTAResponse_helpers.hpp>
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. | |
 Public Member Functions inherited from GFunction | |
| GFunction (void) | |
| Void constructor. | |
| GFunction (const GFunction &function) | |
| Copy constructor. | |
| virtual | ~GFunction (void) |
| Destructor. | |
| GFunction & | operator= (const GFunction &function) |
| Assignment operator. | |
Protected Attributes | |
| const GCTAResponseIrf * | m_rsp |
| CTA response. | |
| const GCTAObservation * | m_obs |
| CTA observation. | |
| const GModelSpatial * | m_model |
| Spatial model. | |
| const GMatrix * | m_rot |
| Rotation matrix. | |
| GEnergy | m_srcEng |
| True photon energy. | |
| GTime | m_srcTime |
| True photon arrival time. | |
| GEnergy | m_obsEng |
| Observed photon energy. | |
| GTime | m_obsTime |
| Observed photon arrival time. | |
| int | m_iter |
| Integration iterations. | |
Additional Inherited Members | |
| Protected Member Functions inherited from GFunction | |
| void | init_members (void) |
| Initialise class members. | |
| void | copy_members (const GFunction &function) |
| Copy class members. | |
| void | free_members (void) |
| Delete class members. | |
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()
|
inline |
Definition at line 934 of file GCTAResponse_helpers.hpp.
Member Function Documentation
◆ eval()
|
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(), and gammalib::twopi.
Member Data Documentation
◆ m_iter
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protected |
Integration iterations.
Definition at line 962 of file GCTAResponse_helpers.hpp.
Referenced by eval().
◆ m_model
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protected |
◆ m_obs
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protected |
◆ m_obsEng
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protected |
Observed photon energy.
Definition at line 960 of file GCTAResponse_helpers.hpp.
Referenced by eval().
◆ m_obsTime
|
protected |
Observed photon arrival time.
Definition at line 961 of file GCTAResponse_helpers.hpp.
Referenced by eval().
◆ m_rot
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protected |
◆ m_rsp
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protected |
◆ m_srcEng
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protected |
◆ m_srcTime
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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
