Merge pull request #40415 from michael-pitt/CMSSW_10_6_X

Add TaggedProton filter for analysis with tagged protons [10_6_X]
cms-sw · Feb 7, 2023 · d3d76d3 · d3d76d3
2 parents 79ea630 + 0ba2b4d
commit d3d76d3
Show file tree

Hide file tree

Showing 3 changed files with 53 additions and 2 deletions.
diff --git a/GeneratorInterface/Core/interface/TaggedProtonHepMCFilter.h b/GeneratorInterface/Core/interface/TaggedProtonHepMCFilter.h
@@ -0,0 +1,24 @@
+#ifndef __TAGGEDPROTONHEPMCFILTER__
+#define __TAGGEDPROTONHEPMCFILTER__
+
+#include "FWCore/MessageLogger/interface/MessageLogger.h"
+
+#include "GeneratorInterface/Core/interface/BaseHepMCFilter.h"
+
+class TaggedProtonHepMCFilter : public BaseHepMCFilter {
+private:
+  const int proton_PDGID_ = 2212;
+  const int neutron_PDGID_ = 2112;
+  const double xiMin_;
+  const double xiMax_;
+  const double oneOverbeamEnergy_;
+  const int nProtons_;
+
+public:
+  explicit TaggedProtonHepMCFilter(const edm::ParameterSet &);
+  ~TaggedProtonHepMCFilter() override = default;
+
+  bool filter(const HepMC::GenEvent *evt) override;
+};
+
+#endif
diff --git a/GeneratorInterface/Core/src/HepMCFilterDriver.cc b/GeneratorInterface/Core/src/HepMCFilterDriver.cc
@@ -3,6 +3,7 @@
 #include "GeneratorInterface/Core/interface/PartonShowerBsHepMCFilter.h"
 #include "GeneratorInterface/Core/interface/PartonShowerCsHepMCFilter.h"
 #include "GeneratorInterface/Core/interface/EmbeddingHepMCFilter.h"
+#include "GeneratorInterface/Core/interface/TaggedProtonHepMCFilter.h"
 #include "GeneratorInterface/Core/interface/PythiaHepMCFilterGammaGamma.h"
 
 #include "FWCore/MessageLogger/interface/MessageLogger.h"
@@ -31,10 +32,12 @@ HepMCFilterDriver::HepMCFilterDriver(const edm::ParameterSet& pset) :
   else if (filterName=="PartonShowerCsHepMCFilter") {
    filter_ = new PartonShowerCsHepMCFilter(filterParameters);
   }
-
+  else if (filterName == "TaggedProtonHepMCFilter") {
+   filter_ = new TaggedProtonHepMCFilter(filterParameters);
+  }
   else if (filterName=="EmbeddingHepMCFilter") {
     filter_ = new EmbeddingHepMCFilter(filterParameters);
-  }
+  }  
   else if (filterName=="PythiaHepMCFilterGammaGamma") {
     filter_ = new PythiaHepMCFilterGammaGamma(filterParameters);
   }

diff --git a/GeneratorInterface/Core/src/TaggedProtonHepMCFilter.cc b/GeneratorInterface/Core/src/TaggedProtonHepMCFilter.cc
@@ -0,0 +1,24 @@
+#include "GeneratorInterface/Core/interface/TaggedProtonHepMCFilter.h"
+
+TaggedProtonHepMCFilter::TaggedProtonHepMCFilter(const edm::ParameterSet &iConfig)
+    : xiMin_(iConfig.getParameter<double>("xiMin")),
+      xiMax_(iConfig.getParameter<double>("xiMax")),
+      oneOverbeamEnergy_(2.0 / iConfig.getParameter<double>("comEnergy")),
+      nProtons_(iConfig.getParameter<int>("nProtons")) {}
+
+bool TaggedProtonHepMCFilter::filter(const HepMC::GenEvent *evt) {
+  // Going through the particle list, and count good protons
+  int nGoodProtons = 0;
+  for (HepMC::GenEvent::particle_const_iterator particle = evt->particles_begin(); particle != evt->particles_end();
+       ++particle) {
+    if ((*particle)->pdg_id() == proton_PDGID_ && 1 == (*particle)->status()) {
+      HepMC::FourVector p4 = (*particle)->momentum();
+      double xi = (1.0 - std::abs(p4.pz()) * oneOverbeamEnergy_);
+      if (xi > xiMin_ && xi < xiMax_)
+        nGoodProtons++;
+      if (nGoodProtons >= nProtons_)
+        return true;
+    }
+  }
+  return false;
+}