Added base code for "RING" bkg subtraction (#2207)

Fixed the method names for G_BIN_EVENTS and G_BKG_SUBTRACT_IRF, which were incorrectly set to older method name values. Added G_BKG_SUBTRACT_RING definition for the ring background subtraction method. Added definition of parameters in 'ctskymap::get_parameters()'. Added method for computing the ring background subtraction (skeleton). Added parameters for defining the ring and integration source region integration radius. Added configuration parameters to parameter file. - roiradius: Region of interest radius - inradius: Inner ring radius - outradius: Outer ring radius - regfile: Region file (or FITS mask file) for exclusion regions.

Added base code for "RING" bkg subtraction (#2207)
Fixed the method names for G_BIN_EVENTS and G_BKG_SUBTRACT_IRF, which were incorrectly set to older method name values. Added G_BKG_SUBTRACT_RING definition for the ring background subtraction method. Added definition of parameters in 'ctskymap::get_parameters()'. Added method for computing the ring background subtraction (skeleton). Added parameters for defining the ring and integration source region integration radius. Added configuration parameters to parameter file. - roiradius: Region of interest radius - inradius: Inner ring radius - outradius: Outer ring radius - regfile: Region file (or FITS mask file) for exclusion regions.
Josh Cardenzana
1 parent 3705c8a9
Showing 3 changed files with 42 additions and 5 deletions
src/ctskymap/ctskymap.cpp
src/ctskymap/ctskymap.hpp
src/ctskymap/ctskymap.par
@@ -32,9 +32,10 @@
 #include "ctskymap.hpp"
  
 /* __ Method name definitions ____________________________________________ */
-#define G_INIT_MAP                 "ctskymap::init_map(GCTAObservation* obs)"
-#define G_BIN_EVENTS                 "ctskymap::bin_events(GCTAObservation*)"
-#define G_BKG_SUBTRACT_IRF     "ctskymap::bkg_subtract_irf(GCTAObservation*)"
+#define G_INIT_MAP                  "ctskymap::init_map(GCTAObservation* obs)"
+#define G_BIN_EVENTS                  "ctskymap::map_events(GCTAObservation*)"
+#define G_BKG_SUBTRACT_IRF    "ctskymap::map_background_irf(GCTAObservation*)"
+#define G_BKG_SUBTRACT_RING  "ctskymap::map_background_ring(GCTAObservation*)"
  
 /* __ Debug definitions __________________________________________________ */
  
@@ -441,6 +442,9 @@ void ctskymap::get_parameters(void)
     // Read ahead parameters
     if (read_ahead()) {
         m_outmap  = (*this)["outmap"].filename();
+        m_roiradius = (this)["roiradius"].real();
+        m_inradius = (this)["m_inradius"].real();
+        m_outradius = (this)["m_outradius"].real();
     }
  
     // Create background map and significance map if background subtraction
@@ -448,6 +452,11 @@ void ctskymap::get_parameters(void)
     if (m_bkgsubtract != "NONE") {
         m_bkgmap = create_map(m_obs);
         m_sigmap = create_map(m_obs);
+
+        // If doing a ring background subtraction, generate an alpha map
+        if (m_bkgsubtract == "RING") {
+            m_alphamap = create_map(m_obs);
+        }
     }
  
     // Write parameters into logger
@@ -566,6 +575,8 @@ void ctskymap::map_background(GCTAObservation* obs)
     // Dispatch to appropriate background estimation method
     if (m_bkgsubtract == "IRF") {
         map_background_irf(obs);
+    } else if (m_bkgsubtract == "RING") {
+        map_background_ring(obs);
     }
  
     // Return
@@ -673,6 +684,23 @@ void ctskymap::map_background_irf(GCTAObservation* obs)
  
  
 /***********************************************************************//**
+ * @brief Estimates the background in sky map based on the ring background method
+ *
+ * @param[in] obs CTA observation.
+ *
+ * @exception GException::invalid_value
+ *            No response information available for observation.
+ *            No background template available in instrument response function.
+ *
+ * Estimates the background in the sky map by summing the events within a ring
+ * centered at a given pixel's position. The pixels in the ring are weighted
+ * also by the background IRF value
+ ***************************************************************************/
+void ctskymap::map_background_ring(GCTAObservation* obs)
+{}
+
+
+/***********************************************************************//**
  * @brief Estimates the background in sky map based on IRF template
  *
  * @param[in] lnE Natural logarithm of energy in MeV.
@@ -71,6 +71,7 @@ protected:
     void map_events(GCTAObservation* obs);
     void map_background(GCTAObservation* obs);
     void map_background_irf(GCTAObservation* obs);
+    void map_background_ring(GCTAObservation* obs);
  
     // Background integration kernel
     class irf_kern : public GFunction {
@@ -92,11 +93,15 @@ protected:
     std::string   m_bkgsubtract; //!< Background subtraction method
     bool          m_publish;     //!< Publish sky map?
     GChatter      m_chatter;     //!< Chattiness
-
+    double        m_roiradius;   //!< Region of interest radius
+    double        m_inradius;    //!< Inner ring radius
+    double        m_outradius;   //!< Outer ring radius
+    
     // Protected members
     GSkyMap       m_skymap;     //!< Sky map
     GSkyMap       m_bkgmap;     //!< Background map
     GSkyMap       m_sigmap;     //!< Significance map
+    GSkyMap       m_alphamap;   //!< Alpha map (if doing "RING" bkg subtraction)
 };
  
  
@@ -42,7 +42,11 @@ yref,     r, a, 22.01,-90,90, &quot;Second coordinate of image center in degrees (DEC
 #
 # Background subtraction parameters
 #==================================
-bkgsubtract, s, a, NONE, NONE|IRF,, "Background subtraction method"
+bkgsubtract, s, a, NONE, NONE|IRF|RING,, "Background subtraction method"
+roiradius,   r, h, 0.0,,, "Region of interest radius"
+inradius,    r, h, 0.6,,, "Inner ring radius"
+outradius,   r, h, 0.8,,, "Outer ring radius"
+regfile,     f, h, NONE,,, "Exclusion regions definition file"
  
 #
 # Standard parameters