Provide a way to avoid saving hits for a list of GEM chambers (eg missing GE11 chambers)

Author: Sunanda

SimG4CMS/Muon/interface/MuonSensitiveDetector.h

@@ -97,6 +97,11 @@ class MuonSensitiveDetector : public SensitiveTkDetector, public Observer<const
   bool haveDemo_;
   bool demoGEM_;
   bool demoRPC_;
+  
+  // For list of GEM DetId to be removed
+  //     DetId = (region * 10000 + ring * 1000 + stattion * 100 +chamber)
+  //     region = 0 for -1; 2 for +1
+  std::vector<int32_t> removeGEMHits_;
 
   G4ProcessTypeEnumerator* theG4ProcessTypeEnumerator;
 

SimG4CMS/Muon/src/MuonSensitiveDetector.cc

@@ -33,6 +33,7 @@
 #include "FWCore/MessageLogger/interface/MessageLogger.h"
 
 #include <iostream>
+#include <sstream>
 
 //#define EDM_ML_DEBUG
 
@@ -60,11 +61,18 @@ MuonSensitiveDetector::MuonSensitiveDetector(const std::string& name,
   haveDemo_ = muonSD.getParameter<bool>("HaveDemoChambers");
   demoGEM_ = muonSD.getParameter<bool>("UseDemoHitGEM");
   demoRPC_ = muonSD.getParameter<bool>("UseDemoHitRPC");
+  removeGEMHits_ = muonSD.getParameter<std::vector<int32_t>>("RemoveGEMHits");
 
 #ifdef EDM_ML_DEBUG
   edm::LogVerbatim("MuonSim") << "create MuonSubDetector " << name << " with dd4hep flag " << dd4hep
                               << " Flags for Demonstration chambers " << haveDemo_ << " for GEM " << demoGEM_
-                              << " for RPC " << demoRPC_;
+                              << " for RPC " << demoRPC_ << " " << removeGEMHits_.size() << " GEM Hits to be removed";
+  if (!removeGEMHits_.empty()) {
+    std::ostringstream st1;
+    for (const auto& id : removeGEMHits_)
+      st1 << " " << id;
+    edm::LogVerbatim("MuonSim") << "IDs to be removed " << st1.str();
+  }
 #endif
   detector = new MuonSubDetector(name);
 
@@ -358,10 +366,21 @@ Local3DPoint MuonSensitiveDetector::FinalStepPositionVsParent(const G4Step* curr
 bool MuonSensitiveDetector::acceptHit(uint32_t id) {
   if (id == 0) {
 #ifdef EDM_ML_DEBUG
-    edm::LogVerbatim("MuonSim") << "DetId " << id << " Flag " << false;
+    edm::LogVerbatim("MuonSim") << "DetId " << std::hex << id << std::dec << " Flag " << false;
 #endif
     return false;
   }
+  if (!removeGEMHits_.empty()) {
+    if (DetId(id).subdetId() == MuonSubdetId::GEM) {
+      int id0 = ((GEMDetId(id).region() - GEMDetId::minRegionId)) * 10000 + GEMDetId(id).ring() * 1000 + GEMDetId(id).station() * 100 + GEMDetId(id).chamber();
+      if  (std::find(removeGEMHits_.begin(), removeGEMHits_.end(), id0) != removeGEMHits_.end()) {
+#ifdef EDM_ML_DEBUG
+	edm::LogVerbatim("MuonSim") << "Remove Hits for DetId " << GEMDetId(id);
+#endif
+	return false;
+      }
+    }
+  }
   bool flag(true);
   if (haveDemo_) {
     int subdet = DetId(id).subdetId();

SimG4CMS/Muon/test/runGEM_cfg.py

@@ -0,0 +1,72 @@
+import FWCore.ParameterSet.Config as cms
+from Configuration.Eras.Era_Run3_DDD_cff import Run3_DDD
+
+process = cms.Process("PROD",Run3_DDD)
+process.load("SimG4CMS.Calo.pythiapdt_cfi")
+process.load('FWCore.MessageService.MessageLogger_cfi')
+process.load("IOMC.EventVertexGenerators.VtxSmearedGauss_cfi")
+process.load("Configuration.Geometry.GeometryExtended2025Reco_cff")
+process.load("Configuration.StandardSequences.MagneticField_cff")
+process.load("Configuration.EventContent.EventContent_cff")
+process.load('Configuration.StandardSequences.Generator_cff')
+process.load('Configuration.StandardSequences.SimIdeal_cff')
+
+process.load("Configuration.StandardSequences.FrontierConditions_GlobalTag_cff")
+from Configuration.AlCa.autoCond import autoCond
+process.GlobalTag.globaltag = autoCond['phase1_2025_realistic']
+
+if 'MessageLogger' in process.__dict__:
+    process.MessageLogger.G4cerr=dict()
+    process.MessageLogger.MuonSim=dict()
+
+process.load("IOMC.RandomEngine.IOMC_cff")
+process.RandomNumberGeneratorService.generator.initialSeed = 456789
+process.RandomNumberGeneratorService.g4SimHits.initialSeed = 9876
+process.RandomNumberGeneratorService.VtxSmeared.initialSeed = 123456789
+
+process.maxEvents = cms.untracked.PSet(
+    input = cms.untracked.int32(200)
+)
+
+process.source = cms.Source("EmptySource")
+
+process.generator = cms.EDProducer("FlatRandomEGunProducer",
+    PGunParameters = cms.PSet(
+        PartID = cms.vint32(13),
+        MinEta = cms.double(1.5),
+        MaxEta = cms.double(2.5),
+        MinPhi = cms.double(-3.1415926),
+        MaxPhi = cms.double(3.1415926),
+        MinE  = cms.double(50.),
+        MaxE  = cms.double(50.)
+    ),
+    Verbosity       = cms.untracked.int32(0),
+    AddAntiParticle = cms.bool(True),
+    firstRun        = cms.untracked.uint32(1)
+)
+
+process.output = cms.OutputModule("PoolOutputModule",
+    process.FEVTSIMEventContent,
+    fileName = cms.untracked.string('simeventMuon.root')
+)
+
+process.Timing = cms.Service("Timing")
+
+process.generation_step = cms.Path(process.pgen)
+process.simulation_step = cms.Path(process.psim)
+process.out_step = cms.EndPath(process.output)
+
+process.g4SimHits.Physics.type = 'SimG4Core/Physics/FTFP_BERT_EMM'
+process.g4SimHits.Physics.Verbosity = 0
+process.g4SimHits.G4Commands = ['/tracking/verbose 1']
+process.g4SimHits.MuonSD.RemoveGEMHits = [1101, 1102, 1103, 1104, 1106, 1108]
+
+# Schedule definition
+process.schedule = cms.Schedule(process.generation_step,
+                                process.simulation_step,
+                                process.out_step
+                                )
+
+# filter all path with the production filter sequence
+for path in process.paths:
+        getattr(process,path)._seq = process.generator * getattr(process,path)._seq

SimG4Core/Application/python/g4SimHits_cfi.py

@@ -373,7 +373,8 @@
         AllMuonsPersistent = cms.bool(True),
         UseDemoHitRPC = cms.bool(True),
         UseDemoHitGEM = cms.bool(True),
-        HaveDemoChambers = cms.bool(True)
+        HaveDemoChambers = cms.bool(True),
+        RemoveGEMHits = cms.vint32()
     ),
     CaloSD = cms.PSet(
         common_heavy_suppression,