Measurements of Age by the Carbon-14 Technique
Measurements of Age by the Carbon-14 Technique
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DOI：
10.1038/1741138a0
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发表时间：
1954-12
期刊：
影响因子：
64.8
通讯作者：
H. Vries;G. Barendsen
中科院分区：
文献类型：
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作者：
H. Vries;G. Barendsen
此外，日全食后不久，在F1层和F2层之间形成了一个新的层；但是，虽然它的密度增加得非常快，但它很快就上升了高度，并融入了正常的F2层，其密度在日食期间保持相当恒定。在喀土穆和伊巴丹，以及在正常的日出期间，在F2层发生的事件序列表明，在相当低的水平产生自由电子，这种电离垂直传输到更高的水平，其中低得多的复合系数导致通常与F2层有关的非常缓慢的衰变速度。Es层；小体日食在零星E层的临界频率上出现一个不寻常的非常深的极小值，时间滞后约90分钟。在喀土穆的全胜之后。虽然在控制期间并没有观察到类似的变化，但如果认为它与这次日食有关，那就是推测了。人们通常会在光学日食之前大约两个小时在电离层寻找可能的粒子日食证据，但这次没有观测到。在日食的前一晚，电离层风暴导致F2层的电子密度值低且波动，风暴效应可能掩盖了可能存在的任何粒子性日食效应。
also, soon after totality, a new layer formed between the F1-and F2-layers; but, although its density increased very rapidly, it quickly rose in height and merged into the normal F2-layer, the density of which had remained quite constant during the eclipse. The sequence of events in the F2-layer both at Khartoum and Ibadan, and also during the normal sunrise period, is suggestive of the generation of free electrons at a fairly low level and the vertical trans-port of this ionization to higher levels where the much lower recombination coefficient results in the very slow rate of decay normally associated with the F2-layer.Es-Layer; Corpuscular Eclipse An unusual and very deep minimum in the critical frequency of the sporadic E-layer occurred with a time-lag of about 90 min. after totality at Khartoum. Although no similar change had been observed during the control period, it would be speculative to suggest that it had any connexion with the eclipse. It is usual to look for possible evidence of a corpuscular eclipse in the ionosphere about two hours before the optical one, but none was observed on this occasion. During the night preceding the eclipse, an ionospheric storm resulted in low and fluctuating values for the electron density in the F2-layer, and it is possible that storm effects would have masked any corpuscular eclipse effects which might have been present.