Interrelations of Upper Atmosphere Disturbance Phenomena in theAuroral Zone

Interrelations of the phenomena of upper atmosphere disturbances in high latitudes, such as magnetic disturbance, auroral displays, anomalous ionization in the ionosphere, X-ray and radio wave emissions, are discussed with special reference 1) to the numerical relations of quantities of the disturbances and 2) to the spatial distribution of disturbance area. As to the numerical relations, the effects of primary electron beams, for example, ionization, excitation and emission of X-ray and radio waves, were shown to be consistent with the observational results, though a considerable scattering of numerical values occurs owing to the fluctuation of energy spectrum of primary electrons. The examination of spatial distribution of disturbance area has led to a conclusion that 1) the electron precipitation responsible for various disturbance phenomana can be divided into three groups, i.e. flash precipitation group, quasisteady precipitation group and noon precipitation group, and 2) these groups would correspond respectively to the electron precipitation from the open-close boundary of magnetic lines of force in geomagnetic cavity, to the electron precipitation from the trapping region, and to that from neutral regions of cavity surface in the day side

ショウワキチ ニオケル チジキK シスウ

昭和基地におけるK指数の撰択は,1959年2月より7月までの半年の資料に基いて行なわれ,その結果,K=9の最小Rangeを2500ガムマと決定した.このRangeにより1959年の1年間に於けるK瓦指数を求め,更にこれを,地球全体の平均的擾乱の指数と見做されるK_p指数と比較した.K_-K_pの関係は顕著な季節変化を示し,K値の小さい方では昼半球の極光帯の擾乱の方が夜半球のそれよりも大きく,逆にK値の大きい方では昼半球の擾乱は夜半球よりも小さいこと,即ち云いかえれば,小さい擾乱は昼半球の極光帯に起り易く,大きい擾乱は夜半球の極光帯に起り易いことが結論された.Range determination for K indices at Syowa Station (69°00\u27S, 35°39\u27E) is briefly discussed first, then the obtained values of K indices for about a year (from Feb. 8, 1959 to Jan. 9,1960) are tabulated. Some discussions are also given, especially on the seasonal variation of regression coefficient of K_. to K_p, which was known from correlation between X_ and K_p for the period

Spatial Distributions of Auroral Zone X-Rays as Viewed from Rocket Altitudes

A single-stage sounding rocket S-210JA-3 was launched to an altitude of 130 km over Syowa Station, Antarctica, on 22 July 1971, for high time resolution image formings of spatial patterns of auroral X-rays. A pair of NaI (T1) scintillation counters, sensitive to X-ray energies of 4 KeV to 40 KeV, was used at mounting angles of 45° and 135° with the rocket axis. They succeeded in scanning a considerable part of the sky through the composite operation of the spinning and coning motions of the rocket, and recorded X-ray fluxes with a magnitude of the order of 10 times the background X-ray flux. As a result, a sequence of iso-photo maps, taken every 5 seconds, of X-ray fluxes with respect to the azimuthal and elevation angle coordinates was achieved covering different altitudes between 73 km and 131 km. The forty-four maps thus obtained during the entire flight of 225 seconds demonstrate the fine structures in spatial patterns, and in particular the existence of several points of origin of auroral X-rays and their temporal changes. It will be shown that the gross spatial character of X-rays is well correlated with those of visual aurora seen from the ground and of ultraviolet emissions measured from on board the same rocket. However, detailed comparisons of X-rays with ultraviolet emissions reveal that none of the fine structures of X-ray distributions were detected by means of the ultraviolet detector. The altitude dependence of the X-ray flux will be discussed taking into account temporal and spatial variations of the auroral luminosity

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

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\u27E 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\u27Es 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\u27Es. 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_) 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_, with a proportionality constant 5×lO^ KR/(electrons/cm^3)^2, such as J(5577)= 5×10^n^2_. 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_ 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

ダイ2ジ ニホン ナンキョク チイキ カンソクタイ チジキ ブモン カンソク ヨホウ

今回の観測の結果,プリンス・ハラルド河岸附近からその北方海域のかなり広い範囲にわたって,VESTINEその他の磁気図による全磁力分布との喰い違いを見出した.この領域が永年変化の大きい領域と殆んど一致していることは,興味ある事実である.尚,途中の航路上に若干の局地異常を認めたが,その主なものは,アフリカ大陸棚の東縁,マダガスカル島の南側及び伊豆大島の北方で,その異常は全磁力でそれぞれ+700γ,+460γ,+470γに達している.その他全磁力の日変化振巾が磁気赤道附近において急激に増大する事実が確認され,加えてこの領域における4月19日の日食の影響が見出されている

ダイ5ジ ナンキョク チイキ カンソクタイ チジキ ブモン ホウコク

昭和基地における地磁気永年変化は,この3年間に約⊿H=-60^γ,⊿Z=+340^γ,⊿D=-37\u27であることが知られた.なおここで注意すべきは,変化の割合が,1960年は前年よりかなり小さくなっているように見えることである.また,直視磁力計によって得られた昭和基地のK指数に,南極地域の他の7基地のK指数を加え,その平均値をK_pと比較した結果,先の論文に述べた結論,即ち1)小擾乱は昼間の極域に多く,大擾乱は夜の極域に多いこと,及び,2)昼間の小擾乱は夜の極域が極めて静穏なときにも現われていること,が再確認された.Geomagnetic secular variation at Syowa Base is briefly discussed on the data of absolute measurements during the period from 1958 to 1960. Some discussions are also given on the relationship of K_p to K_s 1959 (the mean K at 8 stations in the southern polar region), concluding that in the dark polar region may occur extremely severe magnetic disturbances as compared with the sunlit polar region, while a slight perturbation persists in the sunlit polar region even for the extremely quiet period in the dark polar region