143 research outputs found
Extreme magnetic field variations during the October 2003 superstorm
From October to November, 2003 the sun became very active. The plural numbers of active region appeared on the solar surface. The most prominent one was the number 486, which yielded extremely large flares X17/4B at 0951UT on October 28, and X10/2B at 2037UT on October 29. These big flares hurled massive coronal mass ejections (CMEs) toward the earth. In this paper the solar-terrestrial relationship during the October super magnetic storms is discussed. Two fast moving clouds of gas from the sun swept the earth and sparked extreme geomagnetic storms producing the big ground magnetic field depressions of approximately - 350nT and - 400nT of Dst. Several interesting magnetic field variations observed in interplanetary space and their relationships to the ground magnetic field variations are discussed. Topics are as follows: 1) magnetic field polarity changes of the north-south component Bz of interplanetary magnetic field conveyed with the interplanetary coronal mass ejections (ICMEs) and their response to the magnetic field variations on the ground, 2) large amplitude tail flapping motions observed in the distant tail at about - 160Re, 3) large amplitude Pc 5 oscillations globally observed on the ground during the recovery phase of the super magnetic storm, and 4) large amplitude Pc 3 ULF waves observed in space from upstream through the magnetosheath to the dusk-side outer magnetosphere
Detection of the onset time of Pi 2 pulsations by using wavelet analysis
We have developed an algorithm for automatic detection of the onset of Pi 2 pulsations by using the wavelet transform. It is found that the Cauchy wavelet with proper parameters has a time resolution higher than that of the Gabor wavelet, and is suitable for detecting Pi 2 onset. It is revealed that the time of power peak of the Cauchy wavelet transform is given within one to three minutes after the onset of Pi 2. This time lag has been automatically compensated in the present algorithm, and it is shown that the onset time of almost all Pi 2 events can be determined with an accuracy of one minute
Similarity and dissimilarity of conjugate relationships of Pi magnetic pulsations observed during excellent similar auroras
Similarity and dissimilarity of conjugate relationships of Pi magnetic pulsations observed during excellent similar auroras at the conjugate stations, Tjornes in Iceland and Syowa Station in Antarctica are examined. The study revealed that characteristic Pi pulsations, Pi 2 pulsations and impulsive Pi 1 pulsations were prominently observed with a close relationship to aurora activities. During the substorm growth phase they showed a good similarity between the conjugate stations. How ever, at the onset of substorm expansion, the appearance of Pi pulsations showed prominent dissimilarity between the conjugate stations, suggesting that there might be some asymmetry of the ionosphere and magnetosphere conditions in between the northern and the southern hemispheres
A cross-correlation analysis of Pi oscillations in auroral luminosity and magnetic field variations
第6回極域科学シンポジウム[OS] 宙空圏11月16日(月) 国立極地研究所 2階 大会議
Pc5 enhancement of auroral arc and modulation of diffuse/pulsating aurora
The Tenth Symposium on Polar Science/Ordinary sessions: [OS] Space and upper atmospheric sciences, Wed. 4 Dec. / Institute of Statistics and Mathematics (ISM) Seminar room 2 (D304) (3rd floor
Magnetometers for Geophysical Use Part 1. Fluxgate Magnetometer with a 0.5-m Length Two-Core Sensor
Integrated Collection of Stem Cell Bank Data, a Data Portal for Standardized Stem Cell Information
世界中で樹立されたiPS細胞の数や疾患の種類が明らかに. 京都大学プレスリリース. 2021-03-19.The past decade has witnessed an extremely rapid increase in the number of newly established stem cell lines. However, due to the lack of a standardized format, data exchange among stem cell line resources has been challenging, and no system can search all stem cell lines across resources worldwide. To solve this problem, we have developed the Integrated Collection of Stem Cell Bank data (ICSCB) (http://icscb.stemcellinformatics.org/), the largest database search portal for stem cell line information, based on the standardized data items and terms of the MIACARM framework. Currently, ICSCB can retrieve >16, 000 cell lines from four major data resources in Europe, Japan, and the United States. ICSCB is automatically updated to provide the latest cell line information, and its integrative search helps users collect cell line information for over 1, 000 diseases, including many rare diseases worldwide, which has been a formidable task, thereby distinguishing itself from other database search portals
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