Inter-Relations among the Upper Atmosphere Disturbance Phenomena in the Auroral Zone

概要

論文の詳細を見る
After the general introduction, characteristics of the world-wide distribution of the current origin for polar magnetic disturbances was examined systematically: positive bay, sharp negative bay, broad negative bay and giant pulsation are studied with special reference to the distribution of their equivalent current systems. Some remarks are also given for the peculiarity of the current system responsible for gaint pulsations (Chapter I). In comparison with the geomagnetic nature in polar disturbances, the world-wide patterns of foEs and h'E are shown in the next chapter. When examined in the light of world-wide pattern, the distribution of ionospheric activity (increase in foEs) is found to be quite similar to the geomagnetic activity around the auroral zone. There is also an evidence for a systematic fall of h'Es throughout the night in the auroral zone (Chapter II). The subsequent chapter is devoted to the description of the world-wide charateristics of aurora, with reference to its altitude distribution pattern, which revealed itself to have strong resemblance to that of h'Es. From the resemblance, the origin of the two phenomena is first concluded to be common, and is suggested to be due to the effect of incoming corpuscular stream which penetrate into the level of the two disturbance phenomena (Chapter III). A brief summary of the statistical results reached in the preceding chapters is given in the next chapter and the problems which are left unsolved in Part I (Chapter I-V) are also summarized. They include the problem of altitude effect on the disturbance phenomena, which is later solved in Chapter VIII (Chapter IV). Subsequent chapters belong to Part II of the present paper, in which the numerical relations among the upper atmosphere disturbance phenomena are mostly discussed. To make clear the problems which will be dealt with in Part II, the physical quantities concerned are examined and selected for establishing inter-relations among the disturbance quantities. Then, the most important of them are concluded to be the magnitude of horizontal disturbance vector in geomagnetic field, maximum electron number density and the height of the level of the maximum density in Es layer or cloud and auroral zenith luminosity of λ5577 (Chapter V). In introducing to part II, the relationship between the maximum number density of electrons in Es (n_<max>) and auroral zenith luminosity of λ5577 (J(5577)) are examinedwith some references to the luminosity of NG based on the data at Syowa Station, the Japanese Antarctic Base. From the examination, it is established here that in an equilibrium state in aurora, J(5577) is proportional to the second power of n_<max>, with a proportionality constant 5×lO^<-10> KR/(electrons/cm^3)^2, such as J(5577)= 5×10^<-10>n^2_<max>. The dependence of the proportionality constant on the altitude of disturbances is also examined. Further, from the dependence on altitude is obtained the dependence of effective thickness of auroral display on altitude, which in connection with the altitude dependence of effective recombination coefficient, is lound to result in only a little altitude effect on the proportionality constant (Chapter VI). The study is further extended to the relationship between the magnitude of horizontal disturbance vector in geomagnetic field (|ΔH|) and auroral zenith luminosity of λ5577 (J(5577)). It is found thatJ(5577) is proportional to the second power of |ΔH| in an equilibrium state, as so is in J-n_<max> relation. But there is a number of factors which modify appreciably the relationship. A consideration, in which the factors are assumed to act on the proportionality constant in terms of a factor due to integration in some cases and of a factor due to impedance effect in the ionosphere in some othes, is developed (cf. Chapters VII and VIII). It is concluded from the consideration above that simple relation holds between |ΔH| and J(5577)
国立極地研究所の論文

Inter-Relations among the Upper Atmosphere Disturbance Phenomena in the Auroral Zone

スポンサーリンク

概要

著者

関連論文

スポンサーリンク