diff --git a/LArCalorimeter/LArG4/LArG4Code/LArG4Code/CalibrationHit.h b/LArCalorimeter/LArG4/LArG4Code/LArG4Code/CalibrationHit.h
index 340425b93c31d8b3f3d1d3a804bbd84a606db1d3..e03ea922a74296e66326285672857d9f1b00260e 100644
--- a/LArCalorimeter/LArG4/LArG4Code/LArG4Code/CalibrationHit.h
+++ b/LArCalorimeter/LArG4/LArG4Code/LArG4Code/CalibrationHit.h
@@ -40,7 +40,7 @@ namespace LArG4 {
       m_energy3(0.)
     {}
 
-    CalibrationHit(LArG4Identifier ident, 
+    CalibrationHit(const LArG4Identifier& ident, 
 		   G4double energy0 = 0.,
 		   G4double energy1 = 0.,
 		   G4double energy2 = 0.,
diff --git a/LArCalorimeter/LArG4/LArG4Code/LArG4Code/LArG4SimpleSD.h b/LArCalorimeter/LArG4/LArG4Code/LArG4Code/LArG4SimpleSD.h
index 683d3f29d8fb28807c7ec7fbda6f884ba322bba0..1b7d3978de0a683a2078d6d8a5d91a44eeb206b7 100644
--- a/LArCalorimeter/LArG4/LArG4Code/LArG4Code/LArG4SimpleSD.h
+++ b/LArCalorimeter/LArG4/LArG4Code/LArG4Code/LArG4SimpleSD.h
@@ -1,9 +1,9 @@
 /*
-  Copyright (C) 2002-2017 CERN for the benefit of the ATLAS collaboration
+  Copyright (C) 2002-2020 CERN for the benefit of the ATLAS collaboration
 */
 
-#ifndef LARG4SIMPLESD_H
-#define LARG4SIMPLESD_H
+#ifndef LARG4CODE_LARG4SIMPLESD_H
+#define LARG4CODE_LARG4SIMPLESD_H
 
 #include "G4VSensitiveDetector.hh"
 
@@ -69,7 +69,7 @@ public:
   G4bool ProcessHits(G4Step* a_step, G4TouchableHistory*) override;
 
   /// First method translates to this - also for fast sims
-  G4bool SimpleHit( LArG4Identifier lar_id , G4double time , G4double energy );
+  G4bool SimpleHit( const LArG4Identifier& lar_id , G4double time , G4double energy );
 
   /// End of athena event processing
   void EndOfAthenaEvent( LArHitContainer* hitContnainer );
diff --git a/LArCalorimeter/LArG4/LArG4Code/LArG4Code/SDWrapper.h b/LArCalorimeter/LArG4/LArG4Code/LArG4Code/SDWrapper.h
index b3411d40b2e14c0d50284051121a276e68d6165d..5e2bc3e0539027f1ec14116270fa080cbdd1b912 100644
--- a/LArCalorimeter/LArG4/LArG4Code/LArG4Code/SDWrapper.h
+++ b/LArCalorimeter/LArG4/LArG4Code/LArG4Code/SDWrapper.h
@@ -1,5 +1,5 @@
 /*
-  Copyright (C) 2002-2017 CERN for the benefit of the ATLAS collaboration
+  Copyright (C) 2002-2020 CERN for the benefit of the ATLAS collaboration
 */
 
 #ifndef LARG4CODE_SDWRAPPER_H
@@ -58,7 +58,7 @@ namespace LArG4
         using SDList_t = std::vector< std::unique_ptr<SDType> >;
 
         /// Construct the wrapper from the output collection name
-        SDWrapper(const std::string& name, const std::string& hitCollectionName, std::string deadHitCollectionName="");
+        SDWrapper(const std::string& name, const std::string& hitCollectionName, const std::string& deadHitCollectionName="");
 
         /// Add an SD to this wrapper
         void addSD(std::unique_ptr<SDType> sd);
diff --git a/LArCalorimeter/LArG4/LArG4Code/src/LArG4SimpleSD.cc b/LArCalorimeter/LArG4/LArG4Code/src/LArG4SimpleSD.cc
index c4ad33d8c76e54764e019edf754a866630629d2c..bf8889111a4c86f2c2cb1a18ba0300568b9937b8 100644
--- a/LArCalorimeter/LArG4/LArG4Code/src/LArG4SimpleSD.cc
+++ b/LArCalorimeter/LArG4/LArG4Code/src/LArG4SimpleSD.cc
@@ -1,5 +1,5 @@
 /*
-  Copyright (C) 2002-2019 CERN for the benefit of the ATLAS collaboration
+  Copyright (C) 2002-2020 CERN for the benefit of the ATLAS collaboration
 */
 
 #include "LArG4Code/LArG4SimpleSD.h"
@@ -136,7 +136,7 @@ G4bool LArG4SimpleSD::ProcessHits(G4Step* a_step,G4TouchableHistory*)
   return result;
 }
 
-G4bool LArG4SimpleSD::SimpleHit( LArG4Identifier lar_id , G4double time , G4double energy )
+G4bool LArG4SimpleSD::SimpleHit( const LArG4Identifier& lar_id , G4double time , G4double energy )
 {
   // Build the hit from the calculator results.
   Identifier id = ConvertID( lar_id );
diff --git a/LArCalorimeter/LArG4/LArG4Code/src/SDWrapper.cc b/LArCalorimeter/LArG4/LArG4Code/src/SDWrapper.cc
index 45c50c3b297c32191b144e09a8f7cf55bcdf589e..924ab1668bf1d0904d015f8ab9f50c1b9f38006a 100644
--- a/LArCalorimeter/LArG4/LArG4Code/src/SDWrapper.cc
+++ b/LArCalorimeter/LArG4/LArG4Code/src/SDWrapper.cc
@@ -1,5 +1,5 @@
 /*
-  Copyright (C) 2002-2019 CERN for the benefit of the ATLAS collaboration
+  Copyright (C) 2002-2020 CERN for the benefit of the ATLAS collaboration
 */
 
 #include "LArG4Code/SDWrapper.h"
@@ -26,7 +26,7 @@ namespace LArG4
     //-------------------------------------------------------------------------
     template<class SDType, class HitContainerType>
     SDWrapper<SDType, HitContainerType>::
-    SDWrapper(const std::string& name, const std::string& hitCollectionName, std::string deadHitCollectionName)
+    SDWrapper(const std::string& name, const std::string& hitCollectionName, const std::string& deadHitCollectionName)
       : G4VSensitiveDetector(name),
         m_hitCollName(hitCollectionName),
         m_hitColl(hitCollectionName),