Small hypervelocity particles captured in aerogel collectors: Location, extraction, handling and storage
Small hypervelocity particles captured in aerogel collectors: Location, extraction, handling and storage
复制标题
气凝胶收集器捕获的超高速小颗粒：位置、提取、处理和存储
DOI：
10.1111/j.1945-5100.2002.tb00860.x
复制
发表时间：
2002
影响因子：
2.2
通讯作者：
P. Palumbo
中科院分区：
文献类型：
--
作者：
A. Westphal;C. Snead;J. Borg;E. Quirico;P. Raynal;M. Zolensky;G. Ferrini;L. Colangeli;P. Palumbo
摘要：自从第一次证明超高速粒子可以在气凝胶收集器中部分完整地被捕获以来，已经过去了大约十年。但是，最初的承诺，部分完整的外星粒子，收集在太空中，尚未实现。调查人员遇到的困难之一是，构成捕获颗粒绝大多数的非常小（10 μm及以下）的颗粒的定位、提取、处理和分析是具有挑战性和繁重的。此外，目前的提取技术往往对收集器的大面积具有破坏性。在此，我们描述了我们为缓解其中一些困难所做的努力。我们已经学会了如何快速有效地定位气凝胶收集器中捕获的粒子，使用最初为实验核天体物理学开发的自动显微镜扫描系统。我们已经学会了如何使用自动显微操作器和玻璃微针作为工具精确地挖掘小型通道和沟渠。这些挖掘只会在很小的区域内对收集器造成破坏--这一特征对于珍贵的星尘收集器中的挖掘可能特别重要。使用可驱动的硅微镊子，我们已经学会了如何提取和存储“裸露”的颗粒-基本上没有气凝胶-小至3 μm的尺寸。我们还开发了一种提取颗粒的技术，沿着它们的终端轨迹，仍然嵌入在小立方体气凝胶块中。我们已经开发出一种新的方法，用于在蚀刻的核径迹中存储非常小的粒子。我们已经将这些技术应用于提取和储存低地球轨道气凝胶收集器（粒子撞击实验，轨道碎片收集器实验，彗星-99）中捕获的颗粒。
Abstract— It has now been about a decade since the first demonstrations that hypervelocity particles could be captured, partially intact, in aerogel collectors. But the initial promise of a bonanza of partially‐intact extraterrestrial particles, collected in space, has yet to materialize. One of the difficulties that investigators have encountered is that the location, extraction, handling and analysis of very small (10 μm and less) grains, which constitute the vast majority of the captured particles, is challenging and burdensome. Furthermore, current extraction techniques tend to be destructive over large areas of the collectors. Here we describe our efforts to alleviate some of these difficulties. We have learned how to rapidly and efficiently locate captured particles in aerogel collectors, using an automated microscopic scanning system originally developed for experimental nuclear astrophysics. We have learned how to precisely excavate small access tunnels and trenches using an automated micromanipulator and glass microneedles as tools. These excavations are only destructive to the collector in a very small area—this feature may be particularly important for excavations in the precious Stardust collectors. Using actuatable silicon microtweezers, we have learned how to extract and store “naked” particles—essentially free of aerogel—as small as 3 μm in size. We have also developed a technique for extracting particles, along with their terminal tracks, still embedded in small cubical aerogel blocks. We have developed a novel method for storing very small particles in etched nuclear tracks. We have applied these techniques to the extraction and storage of grains captured in aerogel collectors (Particle Impact Experiment, Orbital Debris Collector Experiment, Comet‐99) in low Earth orbit.