Measurement the building up factor of Γ-ray in tissue-equivalent material.

The attenuation coefficients and building up factor (BF) of two different specimens of organic compound (paraffin wax) and sodium chloride structures were measured using gamma rays from radioactive sources (124Am, 137Cs, 226Ra) with energies (60, 662, 186, 242, 295, 352, 609, 1120, 1765) keV respectively. These two samples were measured with a gamma ray integrated computer spectrometer (ICS). This system is controlled by a computer using a custom-written programme and is linked to a sodium iodide activated thallium detector that measures just 1.5 inches by 1.5 inches. The radioactive source and detector were placed in the same room as the specimen. There was a 900-second accumulation time. With the (USX PCI) software, we were able to calculate the photopeak, net area, and FWHM of photopeak. Measured data was compared to the ICRU Report 44 value. When an organic compound and sodium chloride are combined, the attenuation coefficients are less than 7% different from what would be expected in human tissue. Results from this study suggest that the materials used for dosimetry could also be used to create tissue phantoms that accurately represent the biological tissues under investigation. [ABSTRACT FROM AUTHOR]