标题： 成像和爆发定位与EXIST高能望远镜 显示英文标题

标题： Imaging and burst location with the EXIST high-energy telescope

摘要： 所提议的EXIST任务的主要仪器是一种编码掩膜高能望远镜（HET），它必须具有宽视场和极好的灵敏度。 必须最大限度地减少系统误差，以便即使在非常长的总积分时间下，成像性能也能接近统计光子极限。 还要求能够在机载计算机上近实时地重建图像，以检测和定位伽马射线暴。 这必须在航天器扫描天空的同时完成。 扫描提供全天空覆盖，并是减少系统误差的关键。 由于HET探测器像素数量非常多，使得EXIST的机载计算问题更加具有挑战性。 已经评估了HET的许多替代设计方案。 采用的基本概念依赖于一个具有两个空间尺度的独特编码掩膜。 已使用蒙特卡罗模拟和分析分析技术来证明该设计以及所提出的两步暴定位程序的能力。 显示英文摘要

摘要： The primary instrument of the proposed EXIST mission is a coded mask high energy telescope (the HET), that must have a wide field of view and extremely good sensitivity. It will be crucial to minimize systematic errors so that even for very long total integration times the imaging performance is close to the statistical photon limit. There is also a requirement to be able to reconstruct images on-board in near real time in order to detect and localize gamma-ray bursts. This must be done while the spacecraft is scanning the sky. The scanning provides all-sky coverage and is key to reducing systematic errors. The on-board computational problem is made even more challenging for EXIST by the very large number of detector pixels. Numerous alternative designs for the HET have been evaluated. The baseline concept adopted depends on a unique coded mask with two spatial scales. Monte Carlo simulations and analytic analysis techniques have been used to demonstrate the capabilities of the design and of the proposed two-step burst localization procedure.