Updating GenFilterTool for derivations

One of the truth generator filter variables (HT including neutrinos) was missing in release 22. This brings forward the variable definition from release 21.2. At the same time I tried to catch a couple of consistency things within the cxx.

PhysicsAnalysis/DerivationFramework/DerivationFrameworkMCTruth/src/GenFilterTool.cxx

 /*
-  Copyright (C) 2002-2022 CERN for the benefit of the ATLAS collaboration
+  Copyright (C) 2002-2023 CERN for the benefit of the ATLAS collaboration
 */
 
 // Class header file
@@ -26,7 +26,22 @@ namespace DerivationFramework {
     return false;
   }
 
+  static bool isFromWZTau(const xAOD::TruthParticle* tp) {
+    ParticleOrigin orig = static_cast<ParticleOrigin>(tp->auxdata<unsigned int>("classifierParticleOrigin"));
+
+    switch(orig) {
+    case ParticleOrigin::WBoson:
+    case ParticleOrigin::ZBoson:
+    case ParticleOrigin::TauLep:
+      return true;
+    default:
+      return false;
+    }
+    return false;
+  }
+
   static const SG::AuxElement::Decorator<float> dec_genFiltHT("GenFiltHT");
+  static const SG::AuxElement::Decorator<float> dec_genFiltHTinclNu("GenFiltHTinclNu");
   static const SG::AuxElement::Decorator<float> dec_genFiltMET("GenFiltMET");
   static const SG::AuxElement::Decorator<float> dec_genFiltPTZ("GenFiltPTZ");
   static const SG::AuxElement::Decorator<float> dec_genFiltFatJ("GenFiltFatJ");
@@ -97,12 +112,13 @@ namespace DerivationFramework {
       return StatusCode::FAILURE;
     }
 
-    float genFiltHT(0.), genFiltMET(0.), genFiltPTZ(0.), genFiltFatJ(0.);
-    ATH_CHECK( getGenFiltVars(truthPC, genFiltHT, genFiltMET, genFiltPTZ, genFiltFatJ) );
+    float genFiltHT(0.), genFiltHTinclNu(0.), genFiltMET(0.), genFiltPTZ(0.), genFiltFatJ(0.);
+    ATH_CHECK( getGenFiltVars(truthPC, genFiltHT, genFiltHTinclNu, genFiltMET, genFiltPTZ, genFiltFatJ) );
 
-    ATH_MSG_DEBUG("Computed generator filter quantities: HT " << genFiltHT/1e3 << ", MET " << genFiltMET/1e3 << ", PTZ " << genFiltPTZ/1e3 << ", FatJ " << genFiltFatJ/1e3 );
+    ATH_MSG_DEBUG("Computed generator filter quantities: HT " << genFiltHT/1e3 << ", HTinclNu " << genFiltHTinclNu/1e3 << ", MET " << genFiltMET/1e3 << ", PTZ " << genFiltPTZ/1e3 << ", FatJ " << genFiltFatJ/1e3 );
 
     dec_genFiltHT(*eventInfo) = genFiltHT;
+    dec_genFiltHTinclNu(*eventInfo) = genFiltHTinclNu;
     dec_genFiltMET(*eventInfo) = genFiltMET;
     dec_genFiltPTZ(*eventInfo) = genFiltPTZ;
     dec_genFiltFatJ(*eventInfo) = genFiltFatJ;
@@ -110,7 +126,7 @@ namespace DerivationFramework {
     return StatusCode::SUCCESS;
   }
 
-  StatusCode GenFilterTool::getGenFiltVars(const xAOD::TruthParticleContainer* tpc, float& genFiltHT, float& genFiltMET, float& genFiltPTZ, float& genFiltFatJ) const {
+  StatusCode GenFilterTool::getGenFiltVars(const xAOD::TruthParticleContainer* tpc, float& genFiltHT, float& genFiltHTinclNu, float& genFiltMET, float& genFiltPTZ, float& genFiltFatJ) const {
     // Get jet container out
     const xAOD::JetContainer* truthjets = nullptr;
     if ( evtStore()->retrieve( truthjets, m_truthJetsName).isFailure() || !truthjets ){
@@ -120,13 +136,15 @@ namespace DerivationFramework {
 
     // Get HT
     genFiltHT = 0.;
+    genFiltHTinclNu = 0.; // this HT definition includes neutrinos from W/Z/tau
     for (const auto *const tj : *truthjets) {
-      if ( tj->pt()>m_MinJetPt && fabs(tj->eta())<m_MaxJetEta ) {
+      if ( tj->pt()>m_MinJetPt && std::abs(tj->eta())<m_MaxJetEta ) {
         ATH_MSG_VERBOSE("Adding truth jet with pt " << tj->pt()
                         << ", eta " << tj->eta()
                         << ", phi " << tj->phi()
                         << ", nconst = " << tj->numConstituents());
         genFiltHT += tj->pt();
+        genFiltHTinclNu += tj->pt();
       }
     }
 
@@ -138,7 +156,7 @@ namespace DerivationFramework {
       if (pdgid==21 && tp->e()==0) continue; // Work around for an old generator bug
       if ( tp->status() %1000 !=1 ) continue; // Stable!
 
-      if ((abs(pdgid)==11 || abs(pdgid)==13) && tp->pt()>m_MinLepPt && fabs(tp->eta())<m_MaxLepEta) {
+      if ((std::abs(pdgid)==11 || std::abs(pdgid)==13) && tp->pt()>m_MinLepPt && std::abs(tp->eta())<m_MaxLepEta) {
         if( isPrompt(tp) ) {
           ATH_MSG_VERBOSE("Adding prompt lepton with pt " << tp->pt()
                           << ", eta " << tp->eta()
@@ -146,9 +164,22 @@ namespace DerivationFramework {
                           << ", status " << tp->status()
                           << ", pdgId " << pdgid);
           genFiltHT += tp->pt();
+          genFiltHTinclNu += tp->pt();
         }
       }
 
+      // include neutrinos from W/Z/Tau in one of the HT definitions
+      // this corresponds to a subset of HT-sliced samples where the HT filter
+      // was configured to include these particles
+      if (tp->isNeutrino() && isFromWZTau(tp)) {
+        ATH_MSG_VERBOSE("Adding neutrino from W/Z/Tau with pt " << tp->pt()
+                        << ", eta " << tp->eta()
+                        << ", phi " << tp->phi()
+                        << ", status " << tp->status()
+                        << ", pdgId " << pdgid);
+        genFiltHTinclNu += tp->pt();
+      }
+
       if (isNonInteracting(pdgid) && isPrompt(tp) ) {
         ATH_MSG_VERBOSE("Found prompt nonInteracting particle with pt " << tp->pt()
                         << ", eta " << tp->eta()
@@ -171,8 +202,8 @@ namespace DerivationFramework {
       if (HepMC::is_simulation_particle(pitr1)) continue;
       if (pitr1->status()!=1) continue;
       // Pick electrons or muons with Pt > MinPt_PTZ and |eta| < m_maxEta
-      if (std::abs(pdgId1) == 11 || abs(pdgId1) == 13) {
-        if (pitr1->pt() >= MinPt_PTZ && fabs(pitr1->eta()) <= MaxEta_PTZ){
+      if (std::abs(pdgId1) == 11 || std::abs(pdgId1) == 13) {
+        if (pitr1->pt() >= MinPt_PTZ && std::abs(pitr1->eta()) <= MaxEta_PTZ){
           for (const xAOD::TruthParticle* pitr2 : *tpc){
             if (pitr2==pitr1) continue;
             if (HepMC::is_simulation_particle(pitr2)) continue;
@@ -181,9 +212,9 @@ namespace DerivationFramework {
             // Pick electrons or muons with Pt > MinPt_PTZ and |eta| < MaxEta_PTZ
             // If AllowSameCharge_PTZ is not true only pick those with opposite charge to the first particle
             // If AllowElecMu_PTZ is true allow also Z -> emu compinations (with charge requirements as above)
-            if ((AllowSameCharge_PTZ  && (abs(pdgId2) == abs(pdgId1) || (AllowElecMu_PTZ && (abs(pdgId2) == 11 || abs(pdgId2) == 13) ) ) ) ||
+            if ((AllowSameCharge_PTZ  && (std::abs(pdgId2) == std::abs(pdgId1) || (AllowElecMu_PTZ && (std::abs(pdgId2) == 11 || std::abs(pdgId2) == 13) ) ) ) ||
                 (!AllowSameCharge_PTZ && (pdgId2 == -1*pdgId1 || (AllowElecMu_PTZ && (pdgId2 == (pdgId1 < 0 ? 1 : -1) * 11 || (pdgId1 < 0 ? 1 : -1) * pdgId2 == 13) ) ) ) ) {
-              if (pitr2->pt() >= MinPt_PTZ && fabs(pitr2->eta()) <= MaxEta_PTZ){
+              if (pitr2->pt() >= MinPt_PTZ && std::abs(pitr2->eta()) <= MaxEta_PTZ){
                 double invMass = (pitr1->p4()+pitr2->p4()).M();
                 double dilepPt = (pitr1->p4()+pitr2->p4()).Pt();
                 // Only consider pair that fall in the mass window