diff --git a/include/ChargedParticle.h b/include/ChargedParticle.h
index e34ea1c..c48d26f 100644
--- a/include/ChargedParticle.h
+++ b/include/ChargedParticle.h
@@ -72,7 +72,6 @@ class ChargedParticle: public TransientParticle {
 
   // Group steps by radiator of course; in the easiest case an entry and exit points;
   std::vector<std::pair<TRef, RadiatorHistory*> > m_RadiatorHistory;
-
   bool m_StopTracing; //!
 
 #ifndef DISABLE_ROOT_IO
diff --git a/include/CherenkovDetector.h b/include/CherenkovDetector.h
index 964124f..80d4924 100644
--- a/include/CherenkovDetector.h
+++ b/include/CherenkovDetector.h
@@ -117,7 +117,7 @@ class CherenkovDetector: public TObject {
 
   // readout ID -> pixel position converter (for external usage)
   std::function<TVector3(long long int)> m_ReadoutIDToPosition; //!
-
+  std::function<TVector3(long long int)> m_ReadoutIDToNormal;	//!
  private:  
   TString m_Name;
   // This is needed for dd4hep cell index decoding;
diff --git a/include/OpticalPhoton.h b/include/OpticalPhoton.h
index c8c0eb6..710d358 100644
--- a/include/OpticalPhoton.h
+++ b/include/OpticalPhoton.h
@@ -31,8 +31,9 @@ class OpticalPhoton: public TransientParticle {
   inline void SetVertexParentMomentum(const TVector3 &momentum){ m_VertexParentMomentum = momentum; };
   inline void SetVolumeCopy(uint64_t copy)                     { m_VolumeCopy = copy; };
   inline void SetDetectionPosition(const TVector3 &position)   { m_DetectionPosition = position; };
+  //inline void SetDetectionMomentum(const TVector3 &momentum)   { m_DetectionMomentum = momentum;}  ///////////////////////////
   inline void SetPhotonDetector(CherenkovPhotonDetector *pd)   { m_PhotonDetector = pd; };
-
+  inline void SetNormalSurface(const TVector3 &nSurface) 	   {m_NormalSurface = nSurface;};////////////////////////////////
   inline void AddReflectionPoint(ReflectionPoint *reflection)  {
     m_ReflectionPoints.push_back(reflection);
   };
@@ -54,7 +55,9 @@ class OpticalPhoton: public TransientParticle {
   inline const TVector3 &GetVertexMomentum( void )       const { return m_VertexMomentum; };
   inline const TVector3 &GetVertexParentMomentum( void ) const { return m_VertexParentMomentum; };
   inline const TVector3 &GetDetectionPosition( void )    const { return m_DetectionPosition; };
-
+  //inline const TVector3 &GetDetectionMomentum( void )    const { return m_DetectionMomentum; };///////////////////////////
+  inline const TVector3 &GetNormalSurface( void ) 		 const { return m_NormalSurface;};////////////////////////////////
+  
   inline bool WasDetected( void )                        const { return m_Detected; };
   inline uint64_t GetVolumeCopy( void )                  const { return m_VolumeCopy; };
 
@@ -78,6 +81,8 @@ class OpticalPhoton: public TransientParticle {
   TRef m_PhotonDetector;
   uint64_t m_VolumeCopy;
   TVector3 m_DetectionPosition;
+  //TVector3 m_DetectionMomentum;
+  TVector3 m_NormalSurface;
   double m_DetectionTime;
 
   // 'true' if the photon was actually detected; QE-based and geometric efficiency accounted; 
@@ -92,7 +97,10 @@ class OpticalPhoton: public TransientParticle {
 
   // Average estimated phi angle; no need to know it precisely (?);
   std::map<CherenkovRadiator*, double> m_Phi;                  //!
-
+ 
+  //Incident angle
+  std::map<CherenkovRadiator*, float> m_Angle;                  //!
+  
 #ifndef DISABLE_ROOT_IO
   ClassDef(OpticalPhoton, 3);
 #endif
diff --git a/source/ChargedParticle.cc b/source/ChargedParticle.cc
index fa194b9..cfd1721 100644
--- a/source/ChargedParticle.cc
+++ b/source/ChargedParticle.cc
@@ -35,7 +35,7 @@ void ChargedParticle::PIDReconstruction(CherenkovPID &pid)
 
     auto pd = photon->GetPhotonDetector();
     const auto irt = pd->GetIRT(photon->GetVolumeCopy());
-    if (!irt) {
+     if (!irt) {
       printf("No photosensor with this cellID found!\n");
       continue;
     } //if
@@ -46,7 +46,17 @@ void ChargedParticle::PIDReconstruction(CherenkovPID &pid)
       if (radiator->m_Locations.size() != zdim+1) continue;
       
       TVector3 phx = photon->GetDetectionPosition();
-      
+	  // ADding Stuff
+	  const auto norm = (photon->GetNormalSurface());
+	  const auto mom  = (1e9*photon->GetVertexMomentum());
+	  photon->m_Angle[radiator]=norm.Dot(mom);
+	  //float  angle = photon->m_Angle[radiator];
+	  //if((angle*(180/M_PI)) > 0)
+      //printf("-->IRT %lf %lf %lf %lf \n",norm.X(),norm.Y(),norm.Z(),180 - (angle*(180/M_PI)));
+      //if((angle*(180/M_PI)) < 0)
+      //printf("-->IRT %lf %lf %lf %lf \n",norm.X(),norm.Y(),norm.Z(),180 + (angle*(180/M_PI)));
+      // up to here
+    	
       // Get effective attenuation length for this radiator, as well as the 
       // parameterization of its rear surface in this particular sector; this is
       // not really a clean procedure for dRICH aerogel, but should be good enough