Zobrazeno 1 - 10
of 98
pro vyhledávání: '"M. Echim"'
Publikováno v:
Geophysical Research Letters, Vol 50, Iss 24, Pp n/a-n/a (2023)
Abstract Observations of a quiet electrostatic auroral arc by the ALIS network on 5 March 2008 are used to infer a two‐dimensional map of the flux of precipitating energy. Among a family of numerical solutions of a stationary magnetosphere—ionosp
Externí odkaz:
https://doaj.org/article/6f786b8ee49c4fd7b76344b49d7a2233
Publikováno v:
Annales Geophysicae, Vol 36, Pp 1521-1535 (2018)
In this paper we discuss numerical simulations that illustrate a physical mechanism leading to the formation of crescent-shaped electron velocity distribution functions at the edges of a high-speed plasma jet impacting on a thin, steep and impenet
Externí odkaz:
https://doaj.org/article/82dfaa73649b42a69cc4757bb11a5183
Publikováno v:
Annales Geophysicae, Vol 34, Pp 437-449 (2016)
In this paper we investigate quantitatively the effect of data gaps for four methods of estimating the amplitude spectrum of a time series: fast Fourier transform (FFT), discrete Fourier transform (DFT), Z transform (ZTR) and the Lomb–Scargle al
Externí odkaz:
https://doaj.org/article/f42d27ddcb9940cd9bd6662a78fbe2f9
Publikováno v:
Annales Geophysicae, Vol 31, Pp 1297-1314 (2013)
We consider cross-field plasma flow inside a field-aligned plasma slab embedded in a uniform background in a 1-dimensional geometry. This situation may arise, for instance, when long-lasting reconnection pulses inject plasma into the inner magneto
Externí odkaz:
https://doaj.org/article/28442411eaea4ed3a30e1973cdfb6f23
Autor:
J. De Keyser, M. Echim
Publikováno v:
Annales Geophysicae, Vol 31, Pp 251-261 (2013)
Strong localized high-altitude auroral electric fields, such as those observed by Cluster, are often associated with magnetospheric interfaces. The type of high-altitude electric field profile (monopolar, bipolar, or more complicated) depends on t
Externí odkaz:
https://doaj.org/article/edf7458d7ced427a8564941815c61870
Publikováno v:
Annales Geophysicae, Vol 30, Pp 283-302 (2012)
On 1 April 2004 the GUVI imager onboard the TIMED spacecraft spots an isolated and elongated polar cap arc. About 20 min later, the Cluster satellites detect an isolated upflowing ion beam above the polar cap. Cluster observations show that the io
Externí odkaz:
https://doaj.org/article/0ebcfa9990d146b7a3b02d028972adde
Publikováno v:
Annales Geophysicae, Vol 29, Pp 771-787 (2011)
Above the polar caps and during prolonged periods of northward IMF, the Cluster satellites detect upward accelerated ion beams with energies up to a few keV. They are associated with converging electric field structures indicating that the acceler
Externí odkaz:
https://doaj.org/article/5fdf965d2d2745c183c8513b4dac48b4
Publikováno v:
Annales Geophysicae, Vol 28, Pp 2027-2046 (2010)
Most of the high-altitude auroral electric fields observed by CLUSTER can be classified into monopolar and bipolar structures. The observations associate monopolar electric fields with polar cap boundary arcs, while bipolar fields tend to be linke
Externí odkaz:
https://doaj.org/article/8892c42181e64645baa9a0f6465eeb6e
Publikováno v:
Nonlinear Processes in Geophysics, Vol 17, Iss 5, Pp 545-551 (2010)
Intermittent fluctuations are the consequence of the dynamic interactions of multiple coherent or pseudo-coherent structures of varied sizes in the stochastic media (Chang, 1999). We briefly review here a recently developed technique, the Rank-Ordere
Externí odkaz:
https://doaj.org/article/c076466fcae5406fb7be8e47919c1645
Autor:
J. De Keyser, M. Echim
Publikováno v:
Annales Geophysicae, Vol 28, Pp 633-650 (2010)
Many auroral and sub-auroral phenomena are manifestations of an underlying magnetosphere-ionosphere coupling. In the electrostatic perspective the associated auroral current circuit describes how the generator (often in the magnetosphere) is connec
Externí odkaz:
https://doaj.org/article/427c181277a94c30a3d412e8adf6f957