Merge pull request #87 from rest-for-physics/jovoy-target-position

Change Axion generator Target Position

Author: jovoy

inc/TRestAxionAnalysisProcess.h

@@ -32,6 +32,9 @@ class TRestAxionAnalysisProcess : public TRestEventProcess {
     /// A pointer to the specific TRestAxionEvent
     TRestAxionEvent* fAxionEvent;  //!
 
+    /// The analysis position in mm with regards to the sun at (0,0,-AU).
+    TVector3 fAnalysisPosition = TVector3(0, 0, 0);  //<
+
     void Initialize() override;
 
     void LoadDefaultConfig();

inc/TRestAxionGeneratorProcess.h

@@ -49,6 +49,9 @@ class TRestAxionGeneratorProcess : public TRestEventProcess {
     /// The target size in mm (or generator source extension) for the generator.
     Double_t fTargetRadius = 800;  //<
 
+    /// The target position in mm with regards to the sun at (0,0,-AU).
+    TVector3 fTargetPosition = TVector3(0, 0, 0);  //<
+
     /// The generator type (solarFlux/flat)
     TString fGeneratorType = "solarFlux";  //<
 

src/TRestAxionAnalysisProcess.cxx

@@ -126,12 +126,13 @@ TRestEvent* TRestAxionAnalysisProcess::ProcessEvent(TRestEvent* evInput) {
     SetObservableValue("energy", fAxionEvent->GetEnergy());
     SetObservableValue("mass", fAxionEvent->GetMass() * units("eV"));
 
-    Double_t x = fAxionEvent->GetPosition().X();
-    Double_t y = fAxionEvent->GetPosition().Y();
+    Double_t x = fAxionEvent->GetPosition().X() - fAnalysisPosition.X();
+    Double_t y = fAxionEvent->GetPosition().Y() - fAnalysisPosition.Y();
     SetObservableValue("posX", x);
     SetObservableValue("posY", y);
     SetObservableValue("posZ", fAxionEvent->GetPosition().Z());
 
+    /// The following only works if the center of the signal is where the analysis position is.
     Double_t r = TMath::Sqrt(x * x + y * y);
     SetObservableValue("R", r);
 

src/TRestAxionGeneratorProcess.cxx

@@ -166,9 +166,12 @@ TRestEvent* TRestAxionGeneratorProcess::ProcessEvent(TRestEvent* evInput) {
 
     /// The axion position must be displaced by the target size.
     /// We always do this. It is independent of generator
-    /// The target is virtually placed at the (0,0,0).
+    /// The target is virtually placed at the (0,0,0) + TargetPosition since the
+    /// experiment is not focussed by the bore but by the whole experiment.
     /// In my opinion the target should be either the optics, or the magnet end bore.
-    /// Then one should place the optics or the magnet end bore at the (0,0,0).
+    /// Then one should place the optics or the magnet end bore at the (0,0,0) + TargetPosition.
+    /// TODO: The target position and the magnetic field have to be in the same spot in x- and y-direction
+    /// apparently.
     ///
     do {
         x = 2 * (fRandom->Rndm() - 0.5);
@@ -178,7 +181,7 @@ TRestEvent* TRestAxionGeneratorProcess::ProcessEvent(TRestEvent* evInput) {
 
     r = TMath::Sqrt(r);
 
-    axionPosition = axionPosition + TVector3(fTargetRadius * x, fTargetRadius * y, 0);
+    axionPosition = axionPosition + TVector3(fTargetRadius * x, fTargetRadius * y, 0) + fTargetPosition;
 
     Double_t mass = fRandom->Uniform(fAxionMassRange.X(), fAxionMassRange.Y());