Microchannel plates (MCP) are widely used for particle detection. The gain of chevron MCPs is related to geometrical parameters, but no study has been done through SIMION simulation. The purpose of this study is to mo...Microchannel plates (MCP) are widely used for particle detection. The gain of chevron MCPs is related to geometrical parameters, but no study has been done through SIMION simulation. The purpose of this study is to model a chevron MCP and its secondary emission process using SIMION and determine the relationship between microchannel plate gain, voltage, channel bias angle, and diameter. Two geometry files simulated MCP electric field and shape, and a Lua program simulated secondary emission. Simulation results showed that MCP gain is proportional to voltage, angles between 5 and 15 degrees maximize gain, and gain is inversely proportional to the diameter. This study accurately simulates a chevron MCP and yields the relationship between gain, voltage, channel bias angle, and diameter. Further studies are needed to simulate electron trajectories for improved precision.展开更多
在空间探测应用领域,石墨烯薄膜因其低厚度特性,成为一种受到研究者关注的新材料.针对利用石墨烯薄膜替代碳膜作为星载薄膜式飞行时间(Time of Flight,TOF)系统中透射薄膜材料的应用情景,采用粒子透射仿真软件SRIM和粒子光学仿真软件SIM...在空间探测应用领域,石墨烯薄膜因其低厚度特性,成为一种受到研究者关注的新材料.针对利用石墨烯薄膜替代碳膜作为星载薄膜式飞行时间(Time of Flight,TOF)系统中透射薄膜材料的应用情景,采用粒子透射仿真软件SRIM和粒子光学仿真软件SIMION进行联用的方法,进行石墨烯薄膜和碳膜在TOF系统中具体表现的计算机仿真模拟,得到了飞行时间谱图、散斑分布与散角、探测效率等指标的对比结果.仿真结果表明,应用于星载TOF系统的石墨烯薄膜相比碳膜表现出更好的质谱分辨、更小的散斑半径和散角以及更高的探测效率,表明使用石墨烯薄膜替代碳膜可明显提升薄膜式TOF系统的性能.对该结论的进一步证明则需要对应的实验测试数据和结果.相关结果可为后续对石墨烯薄膜进行实际测试以及其他相关研究提供参考.展开更多
静电四级透镜具有优越的电子光学聚焦成像性能,单一静电四极透镜可实现电子束线聚焦,组合静电四极透镜系统拥有点聚焦的能力。文中对实现点聚焦的双静电四极透镜系统相关参数进行了计算,利用电子光学软件SIMION仿真发现,静电四极透镜之...静电四级透镜具有优越的电子光学聚焦成像性能,单一静电四极透镜可实现电子束线聚焦,组合静电四极透镜系统拥有点聚焦的能力。文中对实现点聚焦的双静电四极透镜系统相关参数进行了计算,利用电子光学软件SIMION仿真发现,静电四极透镜之间的畸变场与两端的边缘场引起的像差会严重影响系统聚焦成像质量。仿真分析了系统像差与发射电子初动能的关系。结果表明:系统在保证点聚焦的情况下,增加电子发射初动能可以有效减小系统像差;当电子初动能增加至1×105 e V时,最大发散角为2°的电子束在聚焦平面上的弥散斑减小至3.2μm×28μm。展开更多
文摘Microchannel plates (MCP) are widely used for particle detection. The gain of chevron MCPs is related to geometrical parameters, but no study has been done through SIMION simulation. The purpose of this study is to model a chevron MCP and its secondary emission process using SIMION and determine the relationship between microchannel plate gain, voltage, channel bias angle, and diameter. Two geometry files simulated MCP electric field and shape, and a Lua program simulated secondary emission. Simulation results showed that MCP gain is proportional to voltage, angles between 5 and 15 degrees maximize gain, and gain is inversely proportional to the diameter. This study accurately simulates a chevron MCP and yields the relationship between gain, voltage, channel bias angle, and diameter. Further studies are needed to simulate electron trajectories for improved precision.
文摘在空间探测应用领域,石墨烯薄膜因其低厚度特性,成为一种受到研究者关注的新材料.针对利用石墨烯薄膜替代碳膜作为星载薄膜式飞行时间(Time of Flight,TOF)系统中透射薄膜材料的应用情景,采用粒子透射仿真软件SRIM和粒子光学仿真软件SIMION进行联用的方法,进行石墨烯薄膜和碳膜在TOF系统中具体表现的计算机仿真模拟,得到了飞行时间谱图、散斑分布与散角、探测效率等指标的对比结果.仿真结果表明,应用于星载TOF系统的石墨烯薄膜相比碳膜表现出更好的质谱分辨、更小的散斑半径和散角以及更高的探测效率,表明使用石墨烯薄膜替代碳膜可明显提升薄膜式TOF系统的性能.对该结论的进一步证明则需要对应的实验测试数据和结果.相关结果可为后续对石墨烯薄膜进行实际测试以及其他相关研究提供参考.
文摘静电四级透镜具有优越的电子光学聚焦成像性能,单一静电四极透镜可实现电子束线聚焦,组合静电四极透镜系统拥有点聚焦的能力。文中对实现点聚焦的双静电四极透镜系统相关参数进行了计算,利用电子光学软件SIMION仿真发现,静电四极透镜之间的畸变场与两端的边缘场引起的像差会严重影响系统聚焦成像质量。仿真分析了系统像差与发射电子初动能的关系。结果表明:系统在保证点聚焦的情况下,增加电子发射初动能可以有效减小系统像差;当电子初动能增加至1×105 e V时,最大发散角为2°的电子束在聚焦平面上的弥散斑减小至3.2μm×28μm。
