Absorbed-dose and dose-equivalent buildup factors of gamma rays including bremsstrahlung and annihilation radiation for water, concrete, iron and lead

Gamma-ray absorbed-dose buildup factors and dose-equivalent buildup factors are calculated considering bremsstrahlung and annihilation radiations using a transport code, PALLAS-PL, SP-Br, for water, concrete, iron and lead for point isotropic sources. Comparisons of the absorbed-dose buildup factors with moments calculations show reasonable agreement. The calculated buildup factors are tabulated for incident energies of 01-15 MeV and for penetration depths as great as 40 mean free paths (mfp). The dose-equivalent buildup factors are recommended for use in radiation protection. (author)