GammaLib

I implemented the support of Galactic coordinates in the GModelSpatialPointSource class. The ra() and dec() methods were removed and everything is now handled via the dir() method. A coordsys parameter was added to the constructors so that spatial point sources can be constructed either for celestial or Galactic coordinates. The XML read() and write() methods support reading and writing of models in both formats. A coordsys() method was added to return the coordinate system (either “CEL” or “GAL”).

The unit tests were adapted.

I also implemented the same logic for the radial spatial models.

Note that I needed to adapt the vector IRF computation for the CTA response cube since they preset the longitude and latitude gradients for the analytical gradient computation. I did not verify whether the radial model still work for CTA for a response cube. This needs to be verified before merging in the code.

Here a verification of the CTA Gaussian fitting. I did a simulation of a short run with the Crab modelled using a Gaussian.

An unbinned ctlike analysis gives

2022-02-11T14:10:03: === GModelSky ===
2022-02-11T14:10:03:  Name ......................: Crab(gauss)
2022-02-11T14:10:03:  Instruments ...............: all
2022-02-11T14:10:03:  Observation identifiers ...: all
2022-02-11T14:10:03:  Model type ................: ExtendedSource
2022-02-11T14:10:03:  Model components ..........: "RadialGaussian" * "PowerLaw" * "Constant" 
2022-02-11T14:10:03:  Number of parameters ......: 7
2022-02-11T14:10:03:  Number of spatial par's ...: 3
2022-02-11T14:10:03:   RA .......................: 83.6299869083885 +/- 0.00328488361252953 [-360,360] deg (free,scale=1,gradient)
2022-02-11T14:10:03:   DEC ......................: 22.0173896271789 +/- 0.00308515134809287 [-90,90] deg (free,scale=1,gradient)
2022-02-11T14:10:03:   Sigma ....................: 0.203480569716262 +/- 0.00207014994880326 [0.01,10] deg (free,scale=1,gradient)
2022-02-11T14:10:03:  Number of spectral par's ..: 3
2022-02-11T14:10:03:   Prefactor ................: 5.77140471417774e-16 +/- 7.7137759382583e-18 [1e-23,1e-13] ph/cm2/s/MeV (free,scale=1e-16,gradient)
2022-02-11T14:10:03:   Index ....................: -2.47526109025108 +/- 0.00917658930436079 [-5,-0]  (free,scale=-1,gradient)
2022-02-11T14:10:03:   PivotEnergy ..............: 300000 [10000,1000000000] MeV (fixed,scale=1000000,gradient)
2022-02-11T14:10:03:  Number of temporal par's ..: 1
2022-02-11T14:10:03:   Normalization ............: 1 (relative value) (fixed,scale=1,gradient)
2022-02-11T14:10:03:  Number of scale par's .....: 0
2022-02-11T14:10:03: 
2022-02-11T14:10:03: Application "ctlike" terminated after 1966 wall clock seconds, consuming 1937.16 seconds of CPU time and generating a carbon footprint of 2.51831 g eCO2.

2022-02-11T17:42:17: === GModelSky ===
2022-02-11T17:42:17:  Name ......................: Crab(gauss)
2022-02-11T17:42:17:  Instruments ...............: all
2022-02-11T17:42:17:  Observation identifiers ...: all
2022-02-11T17:42:17:  Model type ................: ExtendedSource
2022-02-11T17:42:17:  Model components ..........: "RadialGaussian" * "PowerLaw" * "Constant" 
2022-02-11T17:42:17:  Number of parameters ......: 7
2022-02-11T17:42:17:  Number of spatial par's ...: 3
2022-02-11T17:42:17:   RA .......................: 83.6348171390305 +/- 0.00361401243640746 [-360,360] deg (free,scale=1,gradient)
2022-02-11T17:42:17:   DEC ......................: 22.0187857002778 +/- 0.0034037032606802 [-90,90] deg (free,scale=1,gradient)
2022-02-11T17:42:17:   Sigma ....................: 0.203652873670136 +/- 0.00222687707982709 [0.01,10] deg (free,scale=1,gradient)
2022-02-11T17:42:17:  Number of spectral par's ..: 3
2022-02-11T17:42:17:   Prefactor ................: 5.82247924314491e-16 +/- 9.31586424094408e-18 [1e-23,1e-13] ph/cm2/s/MeV (free,scale=1e-16,gradient)
2022-02-11T17:42:17:   Index ....................: -2.4916135685806 +/- 0.0121500519851846 [-5,-0]  (free,scale=-1,gradient)
2022-02-11T17:42:17:   PivotEnergy ..............: 300000 [10000,1000000000] MeV (fixed,scale=1000000,gradient)
2022-02-11T17:42:17:  Number of temporal par's ..: 1
2022-02-11T17:42:17:   Normalization ............: 1 (relative value) (fixed,scale=1,gradient)
2022-02-11T17:42:17:  Number of scale par's .....: 0
2022-02-11T17:42:17: 
2022-02-11T17:42:17: Application "ctlike" terminated after 43 wall clock seconds, consuming 24.7518 seconds of CPU time and generating a carbon footprint of 0.0321773 g eCO2.

Also using galactic coordinates works:

2022-02-11T17:48:35: === GModelSky ===
2022-02-11T17:48:35:  Name ......................: Crab(gauss)
2022-02-11T17:48:35:  Instruments ...............: all
2022-02-11T17:48:35:  Observation identifiers ...: all
2022-02-11T17:48:35:  Model type ................: ExtendedSource
2022-02-11T17:48:35:  Model components ..........: "RadialGaussian" * "PowerLaw" * "Constant" 
2022-02-11T17:48:35:  Number of parameters ......: 7
2022-02-11T17:48:35:  Number of spatial par's ...: 3
2022-02-11T17:48:35:   GLON .....................: 184.554678201013 +/- 0.00340841083645764 [-360,360] deg (free,scale=1,gradient)
2022-02-11T17:48:35:   GLAT .....................: -5.7807075777309 +/- 0.00336318681732812 [-90,90] deg (free,scale=1,gradient)
2022-02-11T17:48:35:   Sigma ....................: 0.203652849059719 +/- 0.00222687673719375 [0.01,10] deg (free,scale=1,gradient)
2022-02-11T17:48:35:  Number of spectral par's ..: 3
2022-02-11T17:48:35:   Prefactor ................: 5.8224792164502e-16 +/- 9.31586360327606e-18 [1e-23,1e-13] ph/cm2/s/MeV (free,scale=1e-16,gradient)
2022-02-11T17:48:35:   Index ....................: -2.49161370620237 +/- 0.0121500521861935 [-5,-0]  (free,scale=-1,gradient)
2022-02-11T17:48:35:   PivotEnergy ..............: 300000 [10000,1000000000] MeV (fixed,scale=1000000,gradient)
2022-02-11T17:48:35:  Number of temporal par's ..: 1
2022-02-11T17:48:35:   Normalization ............: 1 (relative value) (fixed,scale=1,gradient)
2022-02-11T17:48:35:  Number of scale par's .....: 0
2022-02-11T17:48:35: 
2022-02-11T17:48:35: Application "ctlike" terminated after 43 wall clock seconds, consuming 24.9629 seconds of CPU time and generating a carbon footprint of 0.0324518 g eCO2.

I also implemented support for Galactic coordinates in the elliptical spatial models. Full support is now available.

Code was merged into devel.