A Phenomenological Theory of Radar Echoes from Meteors
A Phenomenological Theory of Radar Echoes from Meteors
复制标题
流星雷达回波的现象学理论
DOI：
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发表时间：
1949
期刊：
影响因子：
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通讯作者：
P. Millman
中科院分区：
文献类型：
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作者：
D. McKinley;P. Millman
自治领天文台和加拿大渥太华的国家研究理事会已经开展了一项综合观测、摄影和雷达观测流星的计划。对观测数据进行了总结，并得出了一般性结论。根据流星回波在雷达显示器上的距离-时间记录，将流星回波分为几种基本类型。这些类型包括指示接近或后退或两者的回声。其他观察到的特征是：回波的持续时间长达几分钟，来自较亮流星的回波结构复杂，回波出现明显延迟。本文提出了一个唯象理论，它涉及高层大气M区的物理条件的若干假设。一个动能机制，连同紫外辐射机制，建议占流星产生的电离。在M区有可见的条纹或斑块，它们形成了一个精细的结构，使得在条纹内，大气的物理性质强调了流星电离的产生和维持，而不是在中间空间产生的电离。根据上述假设，对所有观察到的回波形式进行了定性解释。其他研究人员在不同波长上的结果与这一分析一致。
The Dominion Observatory and the National Research Council, Ottawa, Canada, have undertaken a program of combined visual, photographic, and radar observations of meteors. The observational data is summarized, and general conclusions have been drawn. The radar echoes obtained from meteors have been classified into basic types according to their appearance on the range-time record of the radar display. These types include echoes indicating approach, or recession, or both. Other observed features are: durations of echoes up to several minutes, complexity of structure for echoes from brighter meteors, and appreciable delays in the appearance of the echoes. A phenomenological theory is proposed, involving a number of postulates concerning the physical conditions in an M region in the upper atmosphere. A kinetic-energy mechanism, together with an ultraviolet radiation mechanism, are suggested to account for the ionization produced by the meteor. In the M region are visualized striae, or patches, which form a fine structure such that, within the striae, the physical properties of the atmosphere emphasize the creation and maintenance of meteoric ionization as compared to the ionization produced in the intervening spaces. A qualitative explanation for all the observed echo forms is advanced on the above hypothesis. The results of other investigators on different wavelengths are consistent with this analysis.