Effective atomic numbers of different types of materials for proton interaction in the energy region 1 keV-10 GeV

The effective atomic numbers (Z(eff)) of different types of materials such as tissues, tissue equivalents, organic compounds, glasses and dosimetric materials have been calculated for total proton interactions in the energy region 1 key-10 GeV. Also, effective atomic numbers relative to water (Z(eff)RW) have been presented in the entire energy region for the materials that show better water equivalent properties. Some human tissues such as adipose tissue, bone compact, muscle skeletal and muscle striated have been investigated in terms of tissue equivalency by comparing Z(eff) values and the better tissue equivalents have been determined for these tissues. With respect to the variation of Z(eff) with kinetic energy, it has been observed that Z(eff) seems to be more or less the same in the energy region 400 keV-10 GeV for the given materials except for the photographic emulsion, calcium fluoride, silicon dioxide, aluminum oxide and Teflon. The values of Z(eff) have found to be constant for photographic emulsion after 1 GeV, for calcium fluoride between 1 MeV and 1 GeV and for silicon dioxide, aluminum oxide and Teflon between 400 keV and 1 GeV. This constancy clearly shows the availability of using Z(eff) in estimating radiation response of the materials at first glance. (C) 2014 Elsevier B.V. All rights reserved.