Search Publications
Motion of Classic and Spontaneous Hot Flow Anomalies Observed by Cluster
Zhang, Hui; Guo, Ruilong; Zhang, Shuai +12 more
The propagation characteristics of hot flow anomalies (HFAs) near the Earth's bow shock are investigated, using observations from the Cluster spacecraft. A data set comprised of 19 classic HFAs (associated with tangential discontinuities, TDs) and 23 spontaneous HFAs (SHFAs, formed in the absence of solar wind discontinuities) was analyzed. For ea…
Cassini-Plasma Interaction Simulations Revealing the Cassini Ion Wake Characteristics: Implications for In-Situ Data Analyses and Ion Temperature Estimates
Wilson, R. J.; Morooka, M. W.; Hadid, L. Z. +7 more
We have used Spacecraft Plasma Interaction Software (SPIS) simulations to study the characteristics (i.e., dimensions, ion depletion, and evolution with the changing spacecraft attitude) of the Cassini ion wake. We focus on two regions, the plasma disk at 4.5-4.7 RS, where the most prominent wake structure will be formed, and at 7.6 R
A New Concept to Measure the Ambipolar Electric Field Driving Ionospheric Outflow
Li, Kun; Wei, Yong; Haaland, Stein
Over the last few decades, the role of ionospheric outflow for the loss of atmospheric constituents, as a plasma supplier to the magnetosphere and hence for the evolution of the Earth's atmosphere has been recognized. A substantial amount of the outflow is thought to be caused by the presence of an ambipolar electric field aligned with the open ma…
Automatic Detection of the Thermal Electron Density From the WHISPER Experiment Onboard CLUSTER II Mission With Neural Networks
Henri, P.; Rauch, J. -L.; Décréau, P. +7 more
The Waves of HIgh frequency and Sounder for Probing Electron density by Relaxation (WHISPER) instrument has been monitoring the bulk properties of the plasma environment around Earth for more than 20 years. Onboard the 3 D Earth magnetospheric CLUSTER II mission, this experiment delivers active and natural electric field spectra, in a frequency in…
The Flux of Flux Ropes Embedded Within Magnetic Clouds Near 5 AU
Zhao, Yan; Feng, Hengqiang; Zhao, Guoqing +3 more
Magnetic clouds (MCs) are an important kind of interplanetary coronal mass ejections and generally treated as giant flux ropes. Previous researches indicates that the rope structure of MCs may be destructed as they move away from the solar surface. In this paper, we made a statistic study of the azimuthal flux of flux ropes embedded within MCs nea…
Earth's Magnetotail as the Reservoir of Accelerated Single and Multicharged Oxygen Ions Replenishing Radiation Belts
Malova, Helmi V.; Zelenyi, Lev M.; Panasyuk, Mikhail I. +4 more
Acceleration of single and multicharged oxygen ions in the perturbed Earth's magnetotail is investigated as the possible source of energetic heavy ions in the ring current. The numerical model is developed that allows evaluating the acceleration of oxygen ions O+ O+8 in two possible scenarios of characteristic perturbations: …
PROBA2 LYRA Occultations: Thermospheric Temperature and Composition, Sensitivity to EUV Forcing, and Comparisons With Mars
Dominique, Marie; Thiemann, Edward M. B.
A method for retrieving temperature and composition from 150 to 350 km in Earth's thermosphere using total number density measurements made via extreme ultraviolet (EUV) solar occultations by the Project for OnBoard Autonomy 2/Large Yield Radiometer (PROBA2/LYRA) instrument is presented. Systematic and random uncertainties are calculated and found…
Results of the Electron Drift Instrument on Cluster
Baumjohann, W.; Torbert, R. B.; Matsui, H. +7 more
The electron drift instrument (EDI) on Cluster pioneered a new method of measuring electric fields, using a beam of electrons to sample the drift velocity over a km-scale gyro orbit. The technique is especially well suited to measuring weak, sub-mV/m, convection fields due to its sensitivity (to both components in the plane perpendicular to B) and…
Charge Exchange Ion Losses in Saturn's Magnetosphere
Clark, G.; Kollmann, P.; Sontag, A.
While various source and loss processes have been proposed for ions in Saturn's magnetosphere, it is not yet well understood what role they play in different regions. In this study, we use a physical model of charge exchange to predict how proton and water group ion intensity profiles evolve over time and compare the results to MIMI/CHEMS measurem…
Tailward Flows in the Vicinity of Fast Earthward Flows
Gunell, H.; Hamrin, M.; Pitkänen, T. +3 more
The occurrence of tailward flows in the magnetotail plasma sheet is closely linked to the dynamics of earthward bursty bulk flows (BBFs). Tailward flows that are observed in the vicinity of these BBFs (or TWABs - Tailward flows around BBFs) may hold unique information on its origin. In this study, we conduct a statistical survey on TWABs by using …