Search Publications
Global geomagnetic responses to the IMF Bz fluctuations during the September/October 2003 high-speed stream intervals
Echer, Ezequiel; Korth, Axel; José Alves Bolzan, Mauricio +1 more
In this paper, we follow the coupling from the solar wind to the Earth's magnetotail, geosynchronous orbit, auroral zone and to the ground, during periods of Alfvénic fluctuations in high-speed solar wind streams (HSSs) and their corotating interaction regions (CIRs). We employ cross-wavelet analysis of magnetic field, particle flux and auroral el…
Statistical survey of day-side magnetospheric current flow using Cluster observations: magnetopause
Fornaçon, Karl-Heinz; Glassmeier, Karl-Heinz; Liebert, Evelyn +2 more
We present a statistical survey of current structures observed by the Cluster spacecraft at high-latitude day-side magnetopause encounters in the close vicinity of the polar cusps. Making use of the curlometer technique and the fluxgate magnetometer data, we calculate the 3-D current densities and investigate the magnetopause current direction, lo…
Mass-loading, pile-up, and mirror-mode waves at comet 67P/Churyumov-Gerasimenko
Altwegg, K.; Glassmeier, K. -H.; Nilsson, H. +23 more
The data from all Rosetta plasma consortium instruments and from the ROSINA COPS instrument are used to study the interaction of the solar wind with the outgassing cometary nucleus of 67P/Churyumov-Gerasimenko. During 6 and 7 June 2015, the interaction was first dominated by an increase in the solar wind dynamic pressure, caused by a higher solar …
Effect of data gaps: comparison of different spectral analysis methods
Mursula, Kalevi; Echim, Marius; Munteanu, Costel +1 more
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 algorithm (LST). We devise two tests: the single-large-gap test, which can probe the effect of a single da…
Two-point observations of low-frequency waves at 67P/Churyumov-Gerasimenko during the descent of PHILAE: comparison of RPCMAG and ROMAP
Goetz, Charlotte; Tsurutani, Bruce T.; Richter, Ingo +11 more
The European Space Agency's spacecraft ROSETTA has reached its final destination, comet 67P/Churyumov-Gerasimenko. Whilst orbiting in the close vicinity of the nucleus the ROSETTA magnetometers detected a new type of low-frequency wave possibly generated by a cross-field current instability due to freshly ionized cometary water group particles. Du…
A statistical study on the shape and position of the magnetotail neutral sheet
Zhang, Tielong; Nakamura, Rumi; Ge, Yasong +3 more
We study the average shape and position of the magnetotail neutral sheet based on magnetic field data obtained by Cluster, Geotail, TC-1, and THEMIS from the years 1995 to 2013. All data in the aberrated GSM (geocentric solar magnetospheric) coordinate system are normalized to the same solar wind pressure 2 nPa and downtail distance X ∼ -20RE…
Modified ion-Weibel instability as a possible source of wave activity at Comet 67P/Churyumov-Gerasimenko
Motschmann, Uwe; Glassmeier, Karl-Heinz; Meier, Patrick
We analytically discuss wave excitation in a homogeneous three component plasma consisting of solar wind protons, electrons and a beam of cometary water ions applied to the plasma environment of comet 67P/Churyumov-Gerasimenko. The resulting dispersion relations are studied in a solar wind rest frame, where a cometary current is solely generated b…
Spatial dimensions of the electron diffusion region in anti-parallel magnetic reconnection
Nakamura, Rumi; Nakamura, Takuma; Haseagwa, Hiroshi
Spatial dimensions of the detailed structures of the electron diffusion region in anti-parallel magnetic reconnection were analyzed based on two-dimensional fully kinetic particle-in-cell simulations. The electron diffusion region in this study is defined as the region where the positive reconnection electric field is sustained by the electron ine…
Ion Bernstein waves in the magnetic reconnection region
Glassmeier, K. -H.; Nakamura, R.; Baumjohann, W. +3 more
Four-dimensional energy spectra and a diagram for dispersion relations are determined for the first time in a magnetic reconnection region in the magnetotail using data from four-spacecraft measurements by the Cluster mission on a spatial scale of 200 km, about 0.1 ion inertial lengths. The energy spectra are anisotropic with an extension in the p…
Proton and heavy ion acceleration by stochastic fluctuations in the Earth's magnetotail
Zimbardo, Gaetano; Greco, Antonella; Artemyev, Anton V. +2 more
Spacecraft observations show that energetic ions are found in the Earth's magnetotail, with energies ranging from tens of keV to a few hundreds of keV. In this paper we carry out test particle simulations in which protons and other ion species are injected in the Vlasov magnetic field configurations obtained by Catapano et al. (2015). These config…