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@@ -24,8 +24,9 @@ Below are some useful material choices. Not all information is provided, but can
  * G4_Fe: iron, a medium-density and medium-Z material that is often used as an absorber for hadronic calorimeters. It has a density of 7.87 g/cm3 and an interaction length of 16.77 cm.
  * G4_W: tungsten, a very high-density and very high-Z material that is suitable for compact and high-resolution electromagnetic calorimeters. It has a density of 19.3 g/cm3 and a radiation length of 0.35 cm.
  * G4_Cu: copper, a high-density and high-Z material that is also used as an absorber for electromagnetic calorimeters. It has a density of 8.96 g/cm3 and a radiation length of 1.43 cm.
+ * G4_BRASS: It has a density of 8.53 g/cm3 and a composition of 70% copper and 30% zinc by mass. It has a radiation length of 1.46 cm and an interaction length of 16.95 cm.
 
 ## For homogenous calorimeters
 
- * G4_PbWO4: lead tungstate (CMS ECAL). Lead tungstate has a very high density of 19.3 g/cm3 and a very short radiation length of 0.35 cm, which 
+ * G4_PbWO4: lead tungstate crystal (CMS ECAL). Lead tungstate has a very high density of 19.3 g/cm3 and a very short radiation length of 0.35 cm, which 
 makes it suitable for compact and high-resolution electromagnetic calorimeters