Merge pull request #44611 from civanch/correct_hgcal_birks

[14_1_X Phase2 SIM] Fixed Birks saturation constants for HGCal scintillators
cms-sw · Apr 8, 2024 · 8f5cee6 · 8f5cee6
2 parents 720e154 + 5700322
commit 8f5cee6
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Showing 2 changed files with 8 additions and 7 deletions.
diff --git a/SimG4CMS/Calo/src/HCalSD.cc b/SimG4CMS/Calo/src/HCalSD.cc
@@ -71,11 +71,6 @@ HCalSD::HCalSD(const std::string& name,
   m_HFDarkening.reset(nullptr);
   m_HcalTestNS.reset(nullptr);
 
-  //static SimpleConfigurable<double> bk1(0.013, "HCalSD:BirkC1");
-  //static SimpleConfigurable<double> bk2(0.0568,"HCalSD:BirkC2");
-  //static SimpleConfigurable<double> bk3(1.75,  "HCalSD:BirkC3");
-  // Values from NIM 80 (1970) 239-244: as implemented in Geant3
-
   dd4hep_ = p.getParameter<bool>("g4GeometryDD4hepSource");
   edm::ParameterSet m_HC = p.getParameter<edm::ParameterSet>("HCalSD");
   useBirk = m_HC.getParameter<bool>("UseBirkLaw");

diff --git a/SimG4Core/Application/python/g4SimHits_cfi.py b/SimG4Core/Application/python/g4SimHits_cfi.py
@@ -367,7 +367,7 @@
         EnergyThresholdForHistoryInGeV = cms.double(0.05)
     ),
     MuonSD = cms.PSet(
-        EnergyThresholdForPersistency = cms.double(1.0),
+        EnergyThresholdForPersistency = cms.double(1.0), # in GeV
         PrintHits = cms.bool(False),
         AllMuonsPersistent = cms.bool(True),
         UseDemoHitRPC = cms.bool(True),
@@ -423,6 +423,9 @@
     HCalSD = cms.PSet(
         common_UseLuminosity,
         UseBirkLaw                = cms.bool(True),
+        # Values of Birks constants from NIM 80 (1970) 239-244:
+        # as implemented in Geant3 required correction due to
+        # biased computation of enery deposition
         BirkC3                    = cms.double(1.75),
         BirkC2                    = cms.double(0.142),
         BirkC1                    = cms.double(0.0060),
@@ -562,9 +565,12 @@
         Verbosity        = cms.untracked.int32(0),
         EminHit          = cms.double(0.0),
         UseBirkLaw       = cms.bool(True),
+        # Values of Birks constants from NIM 80 (1970) 239-244:
+        # as implemented in Geant3 required correction due to
+        # biased computation of enery deposition
         BirkC3           = cms.double(1.75),
         BirkC2           = cms.double(0.142),
-        BirkC1           = cms.double(0.0052),
+        BirkC1           = cms.double(0.0060),
         FiducialCut      = cms.bool(False),
         DistanceFromEdge = cms.double(1.0),
         StoreAllG4Hits   = cms.bool(False),