Bazı Biyolojik Bileşiklerin Kütlesel Zayıflatma Katsayılarının Monte Carlo Yöntemi ile Hesaplanması

Bu çalışma insan vücudunda bulunan 13 biyolojik numunenin toplam kütlesel zayıflatma katsayılarını Monte Carlo yöntemi ile hesaplamayı amaçlamaktadır. Simülasyonlarda, noktasal bir foton kaynağı, tek enerjili fotonları paralel bir demet şeklinde silindirik bir soğurucuya yönlendirmiş ve soğurucunun arkasına disk şeklinde küçük bir vakum dedektör yerleştirilmiştir. Problem geometrisindeki tüm bileşenler numune dışındaki materyallerle etkileşimi önlemek için bir vakum küresi ile çevrelenmiştir. Bu şekilde, simülasyon düzeneği dedektör akısına saçılan fotonların katkı yapmamasını sağlamıştır. Simülasyonlar, 10 keV-20 MeV enerji aralığında 36 farklı foton enerjisinde gerçekleştirilmiştir. Çalışmanın sonuçları literatürde var olan ölçüm değerleri ve teorik veriler ile çok iyi uyum göstermektedir ve Monte Carlo tekniğinin kütlesel zayıflatma katsayılarının hesaplanması için bir alternatif olarak kullanılabileceğini ortaya çıkarmıştır.

Anahtar Kelimeler:

Fotonlar, Kütlesel zayıflama katsayısı, Biyolojik materyaller, Monte Carlo simülasyonları

Monte Carlo Calculation of Mass Attenuation Coefficients of Some Biological Compounds

This study aims to compute total mass attenuation coefficients of thirteen biological samples found in human body using the well-established Monte Carlo method. The simulations utilize a point photon source which emits mono-energetic photons directed as a parallel beam toward the cylindrical absorber behind which was placed a small disc-shaped vacuum detector. All the components in the problem geometry were surrounded by a vacuum sphere to avoid any interactions in materials other than the sample. In this manner, the simulation setup ensures that no scattered photons contribute to the flux in the detector. The simulations were carried out at thirty-six different photon energies between 10 keV-20 MeV. The results of this study indicate very good agreement with theoretical data and measurement values available in literature and indicate that Monte Carlo technique may be used as an alternative for calculations of mass attenuation coefficients.

Keywords:

Photons, Mass attenuation coefficient, Biological materials, Monte Carlo Simulations,

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