LAUSR

Abstract The aim of present work is to examine the radiation interaction properties of muscle, cortical bone, lungs and their tissue equivalent materials in variety of radiation based dosimetric applications. The radiation interaction parameters like photon fluence rate, energy fluence rate, kerma, relative kerma, effective atomic number (Zeff) and computed tomography (CT) number for tissues and their various equivalent materials for energies 60-, 81-, 122-, 184-, 356-,511-, 662-, 834- and 1120-keV respectively are investigated. Effective atomic numbers (Zeff) of tissue equivalent materials have been assigned using anon-destructive experimental technique of multiple back-scattering of 662 keV photons. The gamma radiation flux of 662 keV photons is detected by 3″x 3″ NaI(Tl) scintillation detector. The numbers of multiply backscattered events, for all the tissue equivalent materials (TEM), are found to be increasing with thickness of TEM and finally saturates. The saturation thickness helps in assigning a precise value of effective atomic number Zeff for tissue equivalent materials. Monte Carlo simulations support the results of present experiments. Kerma and relative kerma for tissue equivalent materials are evaluated for various gamma photon energies available from standard radioisotope sources. CT number of these tissues and their equivalent materials are evaluated for the first time for which no data are available for comparison with present results.