title: Spectra of primary X-ray and secondary photons from shielding materials for 4--30 MV X-rays.
mesh_terms: D003252:Construction Materials; D007501:Iron; D007854:Lead; D011835:Radiation Protection; D011882:Radiotherapy, High-Energy / Q000295:instrumentation; D012542:Scattering, Radiation; D013057:Spectrum Analysis; D014867:Water; D014964:X-Ray Therapy / Q000295:instrumentation; D014965:X-Rays
chemical_list: D014867:Water; D007854:Lead; D007501:Iron