title: Lipowitz metal shielding thickness for dose reduction of 6-20 MeV electrons.
abstract: The relative dose reduction by Lipowitz metal of 6 to 20 MeV electrons from a Varian Associates Clinac-20 linear accelerator has been measured using a parallel plate thin wall ionization chamber. Metal thickness required for a 5% attenuation level for a 10 X 10 cm2 field are as follows: 6 MeV-2.3 mm, 9 MeV-4.4 mm, 12 MeV-8.5 mm, 16 MeV--18.0 mm, 20 MeV-25.0 mm.
mesh_terms: D006801:Humans; D011837:Radiation-Protective Agents; D011878:Radiotherapy / Q000295:instrumentation*; D011879:Radiotherapy Dosage
chemical_list: D011837:Radiation-Protective Agents