Merge branch 'patch-10' into 'master'

Adding a comment to `LArG4BirksLaw.cc` to preserve our current knowledge.

See merge request atlas/athena!34929

LArCalorimeter/LArG4/LArG4Code/src/LArG4BirksLaw.cc

@@ -18,6 +18,7 @@ double LArG4BirksLaw::operator () (double dE, double dX, double EField) const {
   double dEdX = dE/dX;
 
   const double kOverField = m_BirksLawK/EField;
+  // NB For a MIP in LAr 1.51 == dEdX/m_LArDensity, so dEcorr1==dE
   double dEcorr1 = dE * (1 + kOverField*1.51) / (1 + kOverField*dEdX/m_LArDensity);  // original corrections
 
   if (dEdX > 12000.0) dEdX = 12000.0;   // The experimental data is available only until dE/dX ~ 12000 MeV/cm