A Monte carlo study on internal charging of onboard subsystem during the July 2004 energetic electron event
A Monte carlo study on internal charging of onboard subsystem during the July 2004 energetic electron event
复制标题
DOI：
--
复制
发表时间：
2009
期刊：
影响因子：
--
通讯作者：
Cheng Hong-fei
中科院分区：
文献类型：
--
作者：
Cheng Hong-fei
内部介质充电(IDC)对暴露在空间辐射环境中的卫星，特别是穿过地球辐射带的卫星来说是一种重大的危害。众所周知，耀斑、日冕物质抛射、SPE和电子风暴等太阳事件是卫星异常的主要原因。在IDC效应的地面模拟中，蒙特卡罗方法在处理复杂几何形状的介质和粒子与材料之间复杂的相互作用方面更加复杂。它应该比一些通常涉及的经验方程更好地工作。本文给出了一个评价IDC效应的实例研究。利用基于蒙特卡罗方法的GEANT工具包，以2004年7月的空间事件为例，利用GOES扫描电子显微镜测得的高能电子通量作为粒子环境数据。为了考察IDC对某些结构的影响，而不是简化的平面介质，构造了一个通用的立方体板子系统，每边有屏蔽体，内部有10个印刷电路板(PCB)。利用GEANT工具包模拟了注入电子与屏蔽体和印刷电路板介质以及电子沉积的相互作用。计算了这些印刷电路板内部的最大电子场强，这有助于定量评估IDC的影响及其与高能粒子环境的关系。在这种情况下，推导出的电介质中的强场足以引起故障的潜在危险。这可能与这次风暴事件期间卫星在轨道上的一些强烈异常有关。因此，本文介绍的方法可以方便地在屏蔽设计中进行易损性评估，降低运行中卫星系统受到IDC损坏的风险。
Internal dielectric charging (IDC)is a significant hazard to satellites which are exposed to the space radiation environment,especially to those passing through the Earth's radiation belts.As known,solar events,such as flares,CMEs,SPEs and electron storms,are the primary causes of satellite anomalies.In ground simulations of IDC effect,the Monte Carlo method is more sophisticated to deal with dielectrics of complicated geometry and the complexity of interactions between particles and materials.It should work better than some empirical equations which are usually involved.In this paper,we present a case study to evaluate IDC effect,utilizing GEANT toolkit which is based on the Monte Carlo method.The space event of July 2004 is taken as an example,and the energetic electron flux measured by GOES SEM is used as the particles environment data.To examine the impact of IDC on some structure rather than simplified planar dielectric,a generalized cubic onboard subsystem is constructed,with shields on each side and 10 Printed Circuit Boards (PCB)inside.The GEANT toolkit is utilized to simulate the interaction of injecting elections with the shields and PCBs' dielectric and the electron deposition.The maximum electron field strength inside these PCBs is calculated,which helps evaluate quantitatively the effect of IDC and its relation to energetic particles environment.In this case,a strong field in the dielectric is derived,which is enough to cause a 'potential hazard' of breakdown.This may be related to some intense anomalies of satellite in orbit during this storm event.Accordingly,the method introduced here can facilitate the vulnerability assessment in the shield design,and reduce the risk of operational satellite systems from IDC damage.