Active and passive shielding design optimization and technical solutions for deep sensitivity hard x-ray focusing telescopes
Active and passive shielding design optimization and technical solutions for deep sensitivity hard x-ray focusing telescopes
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深灵敏度硬X射线聚焦望远镜主被动屏蔽设计优化及技术方案
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发表时间：
2005
期刊：
影响因子：
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通讯作者：
B. Negri
中科院分区：
文献类型：
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作者：
G. Malaguti;G. Pareschi;P. Ferrando;E. Caroli;G. Di Cocco;L. Foschini;S. Basso;S. del Sordo;F. Fiore;A. Bonati;G. Lesci;J. M. Poulsen;F. Monzani;A. Stevoli;B. Negri
10-100千电子伏的电磁波谱区域包含了我们对高能天体物理学中一些关键问题的理解的巨大改进的潜力。另一方面，由于对灵敏度（1毫秒积分时间在20-40 keV内的μCrab分数）和成像（1015”角分辨率）的要求，在这个波段对宇宙的深入检查仍然缺乏。目前提出的使命设想是基于长焦距、掠入射、多层光学器件，再加上空间分辨率为几百微米的焦平面探测器。所需的8至50米的大焦距可通过可扩展的光具座（如HEXITSAT、NEXT和努斯塔飞行任务所预见的）或编队飞行方案（如Simbol-X和XEUS）来实现。虽然最终的望远镜设计将需要在所有相关参数（焦距、板尺度值、角分辨率、视场、探测器尺寸以及由于探测器死区和望远镜渐晕而导致的灵敏度下降）之间进行详细的权衡分析，但必须极其关注背景最小化。在这方面，关键问题是代表被动挡板系统，在大焦距的情况下，需要特别的设计评估，并通过主动/被动屏蔽的几何形状和材料。在这项工作中，硬X射线望远镜的预期背景的研究结果，其所需的灵敏度的影响，连同可能的实施设计概念的主动和被动屏蔽在未来的卫星飞行任务的框架，进行了讨论。
The 10-100 keV region of the electromagnetic spectrum contains the potential for a dramatic improvement in our understanding of a number of key problems in high energy astrophysics. A deep inspection of the universe in this band is on the other hand still lacking because of the demanding sensitivity (fraction of μCrab in the 20-40 keV for 1 Ms integration time) and imaging (≈ 15" angular resolution) requirements. The mission ideas currently being proposed are based on long focal length, grazing incidence, multi-layer optics, coupled with focal plane detectors with few hundreds μm spatial resolution capability. The required large focal lengths, ranging between 8 and 50 m, can be realized by means of extendable optical benches (as foreseen e.g. for the HEXITSAT, NEXT and NuSTAR missions) or formation flight scenarios (e.g. Simbol-X and XEUS). While the final telescope design will require a detailed trade-off analysis between all the relevant parameters (focal length, plate scale value, angular resolution, field of view, detector size, and sensitivity degradation due to detector dead area and telescope vignetting), extreme attention must be dedicated to the background minimization. In this respect, key issues are represented by the passive baffling system, which in case of large focal lengths requires particular design assessments, and by the active/passive shielding geometries and materials. In this work, the result of a study of the expected background for a hard X-ray telescope is presented, and its implication on the required sensitivity, together with the possible implementation design concepts for active and passive shielding in the framework of future satellite missions, are discussed.