Energy absorption buildup factor studies in water, air and concrete up to 100 mfp using G-P fitting formula

The energy absorption buildup factors for water, air and concrete have been calculated up to a penetration depth of 100 mean free paths using 5-parameter Geometric Progression formula, in the energy range of 0.015-15.0 MeV. The results up to 40 mfp have been compared with the available standard data, whereas the buildup factors of these materials beyond 40 mfp and up to 100 mfp are new to the available literature. (author)