K. Keika
Austrian Academy of Sciences
5 Papers
55 Citations
K. Keika is an academic researcher from Austrian Academy of Sciences. The author has contributed to research in topics: Plasma sheet & Solar wind. The author has an hindex of 5, co-authored 5 publications.
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Papers
Response of the inner magnetosphere and the plasma sheet to a sudden impulse
K. Keika,Rumi Nakamura,Wolfgang Baumjohann,Andrei Runov,Andrei Runov,Taku Takada,Taku Takada,Martin Volwerk,T. L. Zhang,B. Klecker,E. A. Lucek,Chris Carr,Henri Rème,Iannis Dandouras,Mats André,Harald U. Frey +15 more
TL;DR: In this paper, the passage of an interplanetary shock caused a sudden compression of the magnetosphere between 0900 UT and 0915 UT on 24 August 2005, and compressive related disturbances of the magnetic and electric field and plasma motion were observed by Double Star Program (DSP) Tan Ce 1 (TC1) and Tan Ce 2 (TC2) in the inner magnetosphere and by Cluster spacecraft in the dawnside plasma sheet.
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Substorm expansion triggered by a sudden impulse front propagating from the dayside magnetopause
K. Keika,Rumi Nakamura,Wolfgang Baumjohann,Vassilis Angelopoulos,Peter Chi,Karl-Heinz Glassmeier,Karl-Heinz Glassmeier,Matthew Fillingim,Werner Magnes,H. U. Auster,Karl-Heinz Fornacon,Geoffrey D. Reeves,Kiyohumi Yumoto,E. A. Lucek,Chris Carr,Iannis Dandouras +15 more
TL;DR: In this article, the authors examined a substorm expansion on 21 June 2007, which occurred <2 min after a solar wind discontinuity accompanied by a dynamic pressure (Pd) increase impinged on the magnetopause.
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A method for estimating the ring current structure and the electric potential distribution using energetic neutral atom data assimilation
Shin'ya Nakano,Genta Ueno,Yusuke Ebihara,M.-C. Fok,Shinichi Ohtani,Pontus Brandt,D. G. Mitchell,K. Keika,T. Higuchi +8 more
TL;DR: In this article, the authors estimate ring current ion distributions and electric potential in the inner magnetosphere by incorporating data from the High-Energy Neutral Atom (HENA) imager on the IMAGE satellite into a kinetic ring current model in the context of data assimilation.
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First application of a Petschek‐type reconnection model with time‐varying reconnection rate to THEMIS observations
Stefan Kiehas,Vladimir Semenov,Marina Kubyshkina,Vassilis Angelopoulos,Rumi Nakamura,K. Keika,Victoria Ivanova,Helfried K. Biernat,Helfried K. Biernat,Wolfgang Baumjohann,Stephen B. Mende,Werner Magnes,Uli Auster,Karl-Heinz Fornacon,Davin Larson,C. W. Carlson,John W. Bonnell,J. P. McFadden +17 more
TL;DR: In this article, the location of the reconnection site and the amount of reconnected magnetic flux out of an analytical time-dependent reconnection model was determined by using Bz and vz signals.
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Plasma sheet oscillations and their relation to substorm development: cluster and double star TC1 case study
Taku Takada,Taku Takada,Rumi Nakamura,Y. Asano,Wolfgang Baumjohann,Andrei Runov,Martin Volwerk,T. L. Zhang,Zoltán Vörös,K. Keika,B. Klecker,Henri Rème,E. A. Lucek,Chris Carr,Harald U. Frey +14 more
TL;DR: In this paper, the authors examined two consecutive plasma sheet oscillation and dipolarization events observed by Cluster in the magnetotail, which are associated with a pseudo-breakup and a small substorm monitored by the IMAGE spacecraft.
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