Monte Carlo simulation study on TeO_2-Bi_O-PbO-MgO-B_2O_3 glass for neutron-gamma ~(252)Cf source

摘要

The present study aims to explore the neutron-gamma attenuation characteristics of the TeO_2-Bi_O-PbO-MgO-B_2O_3 glasses based on MCNPX simulation and theoretical calculations. ~(252)Cf neutron source is important as it emits both neutron and gamma and thus its shielding is essential. The glass samples were irradiated by the ~(252)Cf neutron sources and the watt fission distribution was used to extract the neutron spectrum, then the obtained results were reported in the presence and absence of the glass sample. Also, the other attenuation parameters such as effective removal cross section, mass removal cross section, mean free path (MFP), half value thickness (HTV), and tenth value thickness (TVT) were demonstrated graphically against neutron. Using Doppler effect gamma spectrum in shielding materials for spontaneous fission ~(252)Cf source was extracted and expressed. The linear attenuation coefficient (μ), MFP, HVT, and TVT for wide energy ranges of incident gamma rays were estimated. Furthermore, oxygen molar volume (OMV) and oxygen packing density (OPD) of the selected glasses by the use of molar volume values show a less tight packing of the glass network and a strong packing in the glass network versus MgO and PbO ratio, respectively. The acquired data represents that glass coded TePbMg5 has the higher fast neutron-gamma-shielding ability in comparison to the rest of the glass materials.