Search Publications
Suprathermal electron spectra in the Venus ionosphere
Coates, A. J.; Zhang, T. L.; Galand, M. +2 more
In this study, a multistream kinetic model is used to derive the suprathermal electron intensity in the Venus ionosphere, to be compared with the observations made by the Analyzer of Space Plasmas and Energetic Atoms (ASPERA-4) Electron Spectrometer (ELS) instrument onboard Venus Express (VEx) on 18 May 2006. Input parameters of the model are chos…
Cluster observations of a cusp diamagnetic cavity: Structure, size, and dynamics
Adamson, E.; Otto, A.; Nykyri, K. +2 more
We have analyzed Cluster magnetic field and plasma data during high-altitude cusp crossing and compared them with high-resolution MHD simulations. Cluster encountered a diamagnetic cavity (DMC) during northward interplanetary magnetic field (IMF) conditions, and as the IMF rotated southward, the spacecraft reencountered the cavity more at the sunw…
Statistical analysis of solar EUV and X-ray flux enhancements induced by solar flares and its implication to upper atmosphere
Le, Huijun; Liu, Libo; Wan, Weixing +1 more
The 0.1-0.8 nm X-ray flux data and 26-34 nm EUV flux data are used to statistically analyze the relationship between enhancement in X-ray flux and that in EUV flux during solar flares in 1996-2006. The EUV enhancement does not linearly increase with X-ray flux from C-class to X-class flares. Its uprising amplitude decreases with X-ray flux. The co…
Relativistic electron acceleration by compressional-mode ULF waves: Evidence from correlated Cluster, Los Alamos National Laboratory spacecraft, and ground-based magnetometer measurements
Sharma, A. S.; Tan, Lun C.; Shao, X. +1 more
Simultaneous observations by Cluster and Los Alamos National Laboratory (LANL) spacecraft and Canadian Array for Real-Time Investigations of Magnetic Activity and International Monitor for Auroral Geomagnetic Effects magnetometer arrays during a sudden storm commencement on 25 September 2001 show evidence of relativistic electron acceleration by c…
Pitch angle distributions of energetic electrons at Saturn
Krupp, N.; Krimigis, S. M.; Mitchell, D. G. +5 more
Pitch angle distributions of energetic electrons (110-365 keV) at Saturn are statistically analyzed for 2005-2009. Using a nondipolar model magnetic field, pitch angle distributions are mapped to the magnetospheric equator and sorted by equatorial crossing distance. The results are quantified using a standard function for the pitch angle distribut…
Heavy-ion flux enhancement in the vicinity of the Martian ionosphere during CIR passage: Mars Express ASPERA-3 observations
Fedorov, A.; Barabash, S.; Futaana, Y. +6 more
A characteristic heavy-ion signature observed in the vicinity of the Martian ionosphere during passages of Corotating Interaction Region (CIR) structures in solar wind is reported. We analyzed data obtained by the IMA/ASPERA-3 onboard the Mars Express (MEX) from September to October 2007. We compared the solar wind velocity at Mars derived from a …
Favorable conditions for energetic electron acceleration during magnetic reconnection in the Earth's magnetotail
Hoshino, M.; Imada, S.; Mukai, T. +1 more
We have studied favorable conditions for energetic electron acceleration during magnetic reconnection in the Earth's magnetosphere using the Geotail data. We have found the strong energetic electron acceleration in some reconnection events. On the other hand, the other reconnection events show weak electron acceleration. To discuss what reconnecti…
Cluster observations of surface waves in the ion jets from magnetotail reconnection
Balogh, A.; Rème, H.; Cattell, C. +5 more
We present a Cluster spacecraft investigation of plasma sheet-confined waves and the associated Poynting flux in strong ion jets near a reconnection region in the geomagnetic tail at ∼-17 Re. Using phase lag analysis, we determine from multispacecraft measurements the phase front, wavelength, and phase velocity of the waves with spacecraft frame f…
Two-dimensional correlation functions for density and magnetic field fluctuations in magnetosheath turbulence measured by the Cluster spacecraft
Zong, Q. -G.; Tu, C. -Y.; Marsch, E. +3 more
Knowledge of multidimensional correlation functions is crucial for understanding the anisotropy of turbulence. The two-dimensional (2-D) spatial correlation functions (SCFs) obtained in previous studies of space plasma turbulence were restricted to large-length scales and covered a limited angular domain of the two-point separation vector with res…
On the origin of fluctuations in the cusp diamagnetic cavity
Adamson, E.; Otto, A.; Nykyri, K. +1 more
We have analyzed Cluster magnetic field and plasma data during high-altitude cusp crossing on 14 February 2003. Cluster encountered a diamagnetic cavity (DMC) during northward interplanetary magnetic field (IMF) conditions, and as IMF rotated southward, the spacecraft reencountered the cavity more at the sunward side. The DMC is characterized by a…