The ionised mesosphere is less understood than other parts of the ionosphere because of the challenges of making appropriate measurements in this complex region. We use rocket borne in situ measurements of absolute electron density by the Faraday rotation technique and accompanying DC-probe measurements to study the effect of particles on the D-region charge balance. Several examples of electron bite-outs, their actual depth as well as simultaneous observations of positive ions are presented. For a better understanding of the various dependencies we use the ratio β/αi (attachment rate over ion–ion recombination coefficient), derived from the electron and ion density profiles by applying a simplified ion-chemical scheme, and correlate this term with solar zenith angle and moon brightness. The probable causes are different for day and night; recent in situ measurements support existing hypotheses for daytime cases, but also reveal behaviour at night hitherto not reported in the literature. Within the large range of β/αi values obtained from the analysis of 28 high latitude night flights one finds that the intensity of scattered sunlight after sunset, and even moonlight, apparently can photodetach electrons from meteoric smoke particles (MSP) and molecular anions. The large range of values itself can best be explained by the variability of the MSPs and by occasionally occurring atomic oxygen impacting on the negative ion chemistry in the night-time mesosphere under disturbed conditions.

中文翻译：

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中间层电子的咬合和其他损耗

由于在这个复杂区域进行适当测量的挑战，电离中间层与电离层的其他部分相比较少被了解。我们通过法拉第旋转技术和伴随的 DC 探针测量使用火箭携带的绝对电子密度原位测量来研究粒子对 D 区电荷平衡的影响。介绍了几个电子咬出的例子，它们的实际深度以及对正离子的同时观察。为了更好地理解各种相关性，我们使用比率 β/αi（离子-离子复合系数上的附着率），通过应用简化的离子化学方案从电子和离子密度分布导出，并将该项与太阳天顶相关联角度和月亮亮度。白天和黑夜的可能原因不同；最近的原位测量支持了白天病例的现有假设，但也揭示了迄今为止文献中未报道的夜间行为。在对 28 次高纬度夜间飞行的分析得到的大范围 β/αi 值中，人们发现日落后散射的阳光甚至月光的强度显然可以将电子从流星烟雾粒子 (MSP) 和分子阴离子中分离出来。大范围的值本身可以最好地解释为 MSP 的可变性以及偶尔发生的原子氧在扰动条件下影响夜间中间层的负离子化学。在对 28 次高纬度夜间飞行的分析得到的大范围 β/αi 值中，人们发现日落后散射的阳光甚至月光的强度显然可以将电子从流星烟雾粒子 (MSP) 和分子阴离子中分离出来。大范围的值本身可以最好地解释为 MSP 的可变性以及偶尔发生的原子氧在扰动条件下影响夜间中间层的负离子化学。在对 28 次高纬度夜间飞行的分析得到的大范围 β/αi 值中，人们发现日落后散射的阳光甚至月光的强度显然可以将电子从流星烟雾粒子 (MSP) 和分子阴离子中分离出来。大范围的值本身可以最好地解释为 MSP 的可变性以及偶尔发生的原子氧在扰动条件下影响夜间中间层的负离子化学。