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Solar Energetic Particle Charge States: An Overview
Klecker, B.; Möbius, E.; Popecki, M. A.
The ionic charge distributions of solar energetic particles (SEP) as observed in interplanetary space provide fundamental information about the origin of these particles, and the acceleration and propagation processes at the Sun and in interplanetary space. In this paper we review the measurements of ionic charge states of energetic particles in i…
Wind in the Solar Corona: Dynamics and Composition
Antonucci, Ester
The dynamics of the solar corona as observed during solar minimum with the Ultraviolet Coronagraph Spectrometer, UVCS, on SOHO is discussed. The large quiescent coronal streamers existing during this phase of the solar cycle are very likely composed by sub-streamers, formed by closed loops and separated by open field lines that are channelling a s…
Mars Global MHD Predictions of Magnetic Connectivity Between the Dayside Ionosphere and the Magnetospheric Flanks
Liemohn, Michael W.; Barabash, Stas; Lundin, Rickard +7 more
Atmospheric photoelectrons have been observed well above the ionosphere of Mars by the ASPERA-3 ELS instrument on Mars Express. To systematically interpret these observations, field lines from two global MHD simulations were analyzed for connectivity to the dayside ionosphere (allowing photoelectron escape). It is found that there is a hollow cyli…
Auroral Plasma Acceleration Above Martian Magnetic Anomalies
Coates, A. J.; Kallio, E.; Fedorov, A. +25 more
Aurora is caused by the precipitation of energetic particles into a planetary atmosphere, the light intensity being roughly proportional to the precipitating particle energy flux. From auroral research in the terrestrial magnetosphere it is known that bright auroral displays, discrete aurora, result from an enhanced energy deposition caused by dow…
Location of Magnetic Reconnection in the Magnetotail
Nagai, Tsugunobu
It is a crucial issue to know where magnetic reconnection takes place in the near-Earth magnetotail for substorm onsets. It is found on the basis of Geotail observations that the factor that controls the magnetic reconnection site in the magnetotail is the solar wind energy input. Magnetic reconnection forms close to (far from) the Earth in the ma…
Microphysics of Magnetic Reconnection
Retinò, Alessandro; Vaivads, Andris; André, Mats
Magnetic reconnection is a universal phenomenon where energy is efficiently converted from the magnetic field to charged particles as a result of global magnetic topology changes during which earlier separated plasma regions become magnetically connected. While the reconnection affects large volumes in space most of the topology changes and of the…
Interaction of the Solar Wind with Weak Obstacles: Hybrid Simulations for Weakly Active Comets and for Mars
Kührt, E.; Motschmann, U.
Obstacles in the solar wind are weak when their extension is small or comparable to the characteristic ion gyroradii. In this case interactions involve kinetic features, and hybrid models are an adequate description. A hybrid code operating on a curvilinear 3D grid and its application to solar wind interaction with weak obstacles is discussed. The…
Energetic Hydrogen and Oxygen Atoms Observed on the Nightside of Mars
Fedorov, A.; Barabash, S.; Lundin, R. +5 more
We present measurements of energetic hydrogen and oxygen atoms (ENAs) on the nightside of Mars detected by the neutral particle detector (NPD) of ASPERA-3 on Mars Express. We focus on the observations for which the field-of-view of NPD was directed at the nightside of Mars or at the region around the limb, thus monitoring the flow of ENAs towards …
ICMEs at High Latitudes and in the Outer Heliosphere. Report of Working Group H
Lario, D.; Balogh, A.; Rodriguez, L. +14 more
Interplanetary coronal mass ejections (ICMEs) propagate into the outer heliosphere, where they can have a significant effect on the structure, evolution, and morphology of the solar wind, particularly during times of high solar activity. They are known to play an important role in cosmic ray modulation and the acceleration of energetic particles. …
IMF Direction Derived from Cycloid-Like Ion Distributions Observed by Mars Express
Coates, A. J.; Kallio, E.; Fedorov, A. +29 more
Although the Mars Express (MEX) does not carry a magnetometer, it is in principle possible to derive the interplanetary magnetic field (IMF) orientation from the three dimensional velocity distribution of pick-up ions measured by the Ion Mass Analyser (IMA) on board MEX because pick-up ions' orbits, in velocity phase space, are expected to gyrate …