Merge pull request #47165 from 24LopezR/FixDisplacedSUSY

Fix in HepMC - G4 interface for displaced SUSY simulation

Author: cmsbuild

SimG4Core/Application/python/g4SimHits_cfi.py

@@ -285,6 +285,7 @@
         MinPhiCut = cms.double(-3.14159265359), ## (radians)
         MaxPhiCut = cms.double(3.14159265359),  ## according to CMS conventions
         ApplyLumiMonitorCuts = cms.bool(False), ## primary for lumi monitors
+        IsSmuon = cms.bool(False),
         Verbosity = cms.untracked.int32(0),
         PDGselection = cms.PSet(
             PDGfilterSel = cms.bool(False), ## filter out unwanted particles

SimG4Core/Generators/interface/Generator.h

@@ -45,6 +45,7 @@ class Generator {
   bool fEtaCuts;
   bool fPhiCuts;
   bool fFiductialCuts;
+  bool fSmuon;
   double theMinPhiCut;
   double theMaxPhiCut;
   double theMinEtaCut;

SimG4Core/Generators/src/Generator.cc

@@ -25,6 +25,7 @@ Generator::Generator(const ParameterSet &p)
       fPtransCut(p.getParameter<bool>("ApplyPtransCut")),
       fEtaCuts(p.getParameter<bool>("ApplyEtaCuts")),
       fPhiCuts(p.getParameter<bool>("ApplyPhiCuts")),
+      fSmuon(p.getParameter<bool>("IsSmuon")),
       theMinPhiCut(p.getParameter<double>("MinPhiCut")),  // in radians (CMS standard)
       theMaxPhiCut(p.getParameter<double>("MaxPhiCut")),
       theMinEtaCut(p.getParameter<double>("MinEtaCut")),
@@ -365,7 +366,7 @@ void Generator::HepMC2G4(const HepMC::GenEvent *evt_orig, G4Event *g4evt) {
           // Decay chain outside the fiducial cylinder defined by theRDecLenCut
           // are used for Geant4 tracking with predefined decay channel
           // In the case of decay in vacuum particle is not tracked by Geant4
-        } else if (2 == status && x2 * x2 + y2 * y2 >= theDecRCut2 && std::abs(z2) < Z_hector) {
+        } else if (2 == status && x2 * x2 + y2 * y2 >= theDecRCut2 && (fSmuon || std::abs(z2) < Z_hector)) {
           toBeAdded = true;
           if (verbose > 1)
             edm::LogVerbatim("SimG4CoreGenerator") << "GenParticle barcode = " << (*pitr)->barcode() << " passed case 2"
@@ -476,7 +477,14 @@ void Generator::particleAssignDaughters(G4PrimaryParticle *g4p, HepMC::GenPartic
       LogDebug("SimG4CoreGenerator::::particleAssignDaughters")
           << "Assigning a " << (*vpdec)->pdg_id() << " as daughter of a " << vp->pdg_id() << " status=" << status;
 
-    if ((status == 2 || (status == 23 && std::abs(vp->pdg_id()) == 1000015) || (status > 50 && status < 100)) &&
+    bool isInList;
+    if (fSmuon) {
+      std::vector<int> fParticleList = {1000011, 1000013, 1000015, 2000011, 2000013, 2000015};
+      isInList = (std::find(fParticleList.begin(), fParticleList.end(), std::abs(vp->pdg_id())) != fParticleList.end());
+    } else {
+      isInList = std::abs(vp->pdg_id()) == 1000015;
+    }
+    if ((status == 2 || (status == 23 && isInList) || (status > 50 && status < 100)) &&
         (*vpdec)->end_vertex() != nullptr) {
       double x2 = (*vpdec)->end_vertex()->position().x();
       double y2 = (*vpdec)->end_vertex()->position().y();