Investigation of Gamma-ray attenuation coefficients for some different tissues

Öz

In this study, the half-value thicknesses, linear and mass attenuation coefficients of biological samples such as adipose tissue, bone, cardiac muscle, liver, lung, muscle skeletal and soft tissue have been measured at 97, 243.79, 344.89, 662, 778.43, 866.27, 962.31, 1112.87, 1173, 1333 and 1407.52 keV energies by using the NaI(Tl) spectrometer. The gamma-rays were obtained from ¹⁵²Eu, ¹³⁷Cs and ⁶⁰Co sources. Also theoretical calculations have been performed in order to obtain the half-value thicknesses, mass and linear attenuation coefficients, and the tenth-value thicknesses at photon energies 0.001 MeV–10 GeV for the some tissues.The experimental linear mass attenuation coefficients, half value layer for tissue components were compared with theoretical values obtained using WinXCOM.

 The half-value thicknesses, mass and linear attenuation coefficients, and the tenth-value thicknesses of tissue compounds have been computed in the wide energy region 1 keV to 10 GeV using an accurate database of photon-interaction cross sections and the WinXCom program. The linear attenuation coefficient for bone is higher than the tissues of cardiac muscle, liver, lung, skeletal muscle and soft tissue. HVL, TVL and mean free path are lower for bone than the tissues of cardiac muscle, liver, lung, skeletal muscle and soft tissue. The studied gamma dosimetric values for the relaxants are useful in medical physics and radiation medicine. Result shows that attenuation and required thickness to achieve certain attenuation power are highly photon energy dependent.

 

Anahtar Kelimeler

• Gamma Attenuation Coefficient; Half-Value Layer HVL,Tenth-value thickness TVL; Gamma Spectrometer

Kaynakça

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