Resolve "Add ZDC benchmark"

Closes #71 (closed)

• neutron example
• photon example

TODO: check crossing angle and make a separate issue on optimizing clustering algorithm

benchmarks/far_forward/analysis/analysis_zdc_neutrons.cxx

@@ -23,6 +23,7 @@
 
 R__LOAD_LIBRARY(libeicd.so)
 R__LOAD_LIBRARY(libDD4pod.so)
+#include "fmt/core.h"
 #include "DD4hep/Detector.h"
 #include "DDG4/Geant4Data.h"
 #include "DDRec/CellIDPositionConverter.h"
@@ -75,43 +76,22 @@ void analysis_zdc_neutrons(const char* input_fname = "sim_zdc_uniform_neutron.ro
   // Theta [mrad]
   auto Thetathr = [](std::vector<dd4pod::Geant4ParticleData> const& input) {
     auto p = input[2];
-    TVector3 mom(p.ps.x, p.ps.y, p.ps.z);
-    // removing crossing angle
-    auto crossing_angle = -0.025; // unit [rad]
-    auto sin_term = std::sin(-crossing_angle);
-    auto cos_term = std::cos(-crossing_angle);
-    auto pz = cos_term * mom.Z() - sin_term * mom.X();
-    auto px = sin_term * mom.Z() + cos_term * mom.X();
-    TVector3 org_mom(px, mom.Y(), pz);
-    return org_mom.Theta()*1000.0;
+    auto theta = p.ps.theta();
+    return theta*1000.0;
   };
 
   // Phi [rad]
   auto Phithr = [](std::vector<dd4pod::Geant4ParticleData> const& input) {
     auto p = input[2];
-    TVector3 mom(p.ps.x, p.ps.y, p.ps.z);
-    // removing crossing angle
-    auto crossing_angle = -0.025; // unit [rad]
-    auto s = std::sin(-crossing_angle);
-    auto c = std::cos(-crossing_angle);
-    auto pz = c*mom.Z() - s*mom.X();
-    auto px = s*mom.Z() + c*mom.X();
-    TVector3 transmom(px, mom.Y(), pz);
-    return transmom.Phi();
+    auto phi = p.ps.phi();
+    return phi;
   };
   
   // Eta
   auto Etathr = [](std::vector<dd4pod::Geant4ParticleData> const& input) {
     auto p = input[2];
-    TVector3 mom(p.ps.x, p.ps.y, p.ps.z);
-    // removing crossing angle
-    auto crossing_angle = -0.025; // unit [rad]
-    auto sin_term = std::sin(-crossing_angle);
-    auto cos_term = std::cos(-crossing_angle);
-    auto pz = cos_term * mom.Z() - sin_term * mom.X();
-    auto px = sin_term * mom.Z() + cos_term * mom.X();
-    TVector3 org_mom(px, mom.Y(), pz);
-    return org_mom.Eta();
+    auto eta = p.ps.eta();
+    return eta;
   };  
 
   // Define variables