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据报导,美国能源部Argonne国家实验室研制出一种小型便携式检测器,用于检测隐藏起来的核武器和核材料。该检测器的核心部分是一个小型砷化镓晶片。涂上硼或锂之后,砷化镓晶片可以检测中子,如核武器使用的裂变物质所释放出的中子。该晶片很小,所需电压不到50 V,在室温下使用可以经受得往相当高的辐射场而不随时间衰变。晶片工作部分的的直径与环型钮扣的直径相当,但比环型钮扣薄。晶片由廉价的常规微处理器技术制作而成。检测的关键是在砷化镓晶片的表面涂上与硼或锂类似的物质。中子撞击到涂层上时产生易于检测的带电粒子流。可以通过改变涂层的类型和厚度使晶片适合具体应用。砷化镓检测器可以辅助国际核查人员阻止走私以及核武器与核材料的非法运用,与其它中子检测器相比,砷化镓检测器具备体积小、耗电少、不需要冷却等许多优点。在砷化镓晶片上刻出圆形小孔,晶片的检测性能有所提高。
According to the report, the Argonne National Laboratory of the U.S. Department of Energy has developed a small portable detector for detecting hidden nuclear and nuclear materials. The heart of the detector is a small GaAs wafer. After being coated with boron or lithium, gallium arsenide chips can detect neutrons, such as those released by nuclear fission materials. The chip is small, the required voltage is less than 50 V, can be used at room temperature to withstand a relatively high radiation field without decay over time. The working part of the wafer has a diameter equal to the diameter of the ring button but thinner than the ring button. The chips are made from inexpensive conventional microprocessor technology. The key is to detect the gallium arsenide wafer coated with boron or lithium-like substances. Neutron collisions with the coating create easily detectable flow of charged particles. The wafer can be tailored to specific applications by changing the type and thickness of the coating. Gallium Arsenide detectors can help international inspectors stop smuggling and the illicit use of nuclear and nuclear materials. Compared with other neutron detectors, gallium arsenide detectors have many advantages, such as small size, low power consumption and no cooling required. Circular holes made in gallium arsenide wafers show improved detection performance.