灵敏度是 γ 射线密度测量系统设计的重要目标之一,本文利用 Monte Carlo 数值方法模拟分析了影响系统灵敏度的各种因素,探讨了提高灵敏度的相关措施。对于设计利用γ 射线与物质相互作用原理探测相关物理量的其他仪器设备也有一定的指...灵敏度是 γ 射线密度测量系统设计的重要目标之一,本文利用 Monte Carlo 数值方法模拟分析了影响系统灵敏度的各种因素,探讨了提高灵敏度的相关措施。对于设计利用γ 射线与物质相互作用原理探测相关物理量的其他仪器设备也有一定的指导意义。展开更多
The article aims to study the possible correlation between the presence and intensity of rainfall X- and T-radiation and low energy neutrons at one specific location in S[io Jos6 dos Campos, SP, Brazil. Monitoring of ...The article aims to study the possible correlation between the presence and intensity of rainfall X- and T-radiation and low energy neutrons at one specific location in S[io Jos6 dos Campos, SP, Brazil. Monitoring of these parameters was carried out from end February to half of June 2013 just in Physics Department of ITA (Technological Institute of Aeronautics). By correlating the data of measurements of intensity of X and ),-radiations with the rainfall it has been found that this meteorological parameter had a significant influence on the background of these radiation profile. A possible reason for this fact is associated with the presence of radon gas in the environment that is dragged to the surface during the occurrences of local rainfall. In relation neutrons, it was possible to note that the rainfall has small influence on this parameter measures.展开更多
Low energy gamma radiation (0.2-10.0) MeV near the Earth's surface has several origins. Primary and secondary cosmic radiations with interactions of very high energy protons (〉 1 GeV) in terrestrial atmosphere a...Low energy gamma radiation (0.2-10.0) MeV near the Earth's surface has several origins. Primary and secondary cosmic radiations with interactions of very high energy protons (〉 1 GeV) in terrestrial atmosphere are the main sources. The second most important source near the surface of the Earth and in the tropical and equatorial regions is the radon gas (Rn-222) that decays in alpha particles and gamma rays in this energy range. Also the telluric radionuclides 238U, 235U, 40K and 232Th in decays produce gamma radiation with different intensities at different locations on the surface of the Earth. Other sources less present are electrical discharges (lightning strikes) and man-made radioactive sources for medical, dental and industrial applications. In this work, it is shown that measurements of these components during all year 2016 are carried out at the ITA (Technological Institute of Aeronautics) campus in Sao Jose dos Campos, SP, Brazil and their possible correlations with atmospheric phenomena.展开更多
文摘The article aims to study the possible correlation between the presence and intensity of rainfall X- and T-radiation and low energy neutrons at one specific location in S[io Jos6 dos Campos, SP, Brazil. Monitoring of these parameters was carried out from end February to half of June 2013 just in Physics Department of ITA (Technological Institute of Aeronautics). By correlating the data of measurements of intensity of X and ),-radiations with the rainfall it has been found that this meteorological parameter had a significant influence on the background of these radiation profile. A possible reason for this fact is associated with the presence of radon gas in the environment that is dragged to the surface during the occurrences of local rainfall. In relation neutrons, it was possible to note that the rainfall has small influence on this parameter measures.
文摘Low energy gamma radiation (0.2-10.0) MeV near the Earth's surface has several origins. Primary and secondary cosmic radiations with interactions of very high energy protons (〉 1 GeV) in terrestrial atmosphere are the main sources. The second most important source near the surface of the Earth and in the tropical and equatorial regions is the radon gas (Rn-222) that decays in alpha particles and gamma rays in this energy range. Also the telluric radionuclides 238U, 235U, 40K and 232Th in decays produce gamma radiation with different intensities at different locations on the surface of the Earth. Other sources less present are electrical discharges (lightning strikes) and man-made radioactive sources for medical, dental and industrial applications. In this work, it is shown that measurements of these components during all year 2016 are carried out at the ITA (Technological Institute of Aeronautics) campus in Sao Jose dos Campos, SP, Brazil and their possible correlations with atmospheric phenomena.