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The Solar Wind as a Turbulence Laboratory
Bruno, Roberto; Carbone, Vincenzo
In this review we will focus on a topic of fundamental importance for both plasma physics and astrophysics, namely the occurrence of large-amplitude low-frequency fluctuations of the fields that describe the plasma state. This subject will be treated within the context of the expanding solar wind and the most meaningful advances in this research f…
Shock Geometry, Seed Populations, and the Origin of Variable Elemental Composition at High Energies in Large Gradual Solar Particle Events
Cohen, C. M. S.; Mewaldt, R. A.; Maclennan, C. G. +5 more
Above a few tens of MeV per nucleon, large, gradual solar energetic particle (SEP) events are highly variable in their spectral characteristics and elemental composition. The origin of this variability has been a matter of intense and ongoing debate. In this paper, we propose that this variability arises from the interplay of two factors-shock geo…
Radial evolution of the electron distribution functions in the fast solar wind between 0.3 and 1.5 AU
McComas, D. J.; Maksimovic, M.; Issautier, K. +8 more
Observed electron distribution functions of the solar wind permanently exhibit three different components: a thermal core and a suprathermal halo, which are always present at all pitch angles, and a sharply magnetic field aligned "strahl" which is usually anti-sunward moving. Whereas Coulomb collisions can explain the relative isotropy of the core…
A statistical study of the properties of interplanetary coronal mass ejections from 0.3 to 5.4 AU
Liu, Y.; Richardson, J. D.; Belcher, J. W.
We make a comprehensive survey of interplanetary coronal mass ejections (ICMEs) observed by the Helios 1 and 2, Ulysses, WIND and ACE spacecraft, which together cover heliocentric distances from 0.3 to 5.4 AU. The signatures used to identify ICMEs are enhanced helium abundances and depressed proton temperatures. We use the ICME list to study the r…
Simultaneous Chandra X ray, Hubble Space Telescope ultraviolet, and Ulysses radio observations of Jupiter's aurora
MacDowall, R. J.; Waite, J. H.; Cravens, T. E. +8 more
Observations of Jupiter carried out by the Chandra Advanced CCD Imaging Spectrometer (ACIS-S) instrument over 24-26 February 2003 show that the auroral X-ray spectrum consists of line emission consistent with high-charge states of precipitating ions, and not a continuum as might be expected from bremsstrahlung. The part of the spectrum due to oxyg…
Magnetic field variations in the Jovian magnetotail induced by solar wind dynamic pressure enhancements
Yokoyama, Takaaki; Tao, Chihiro; Kataoka, Ryuho +2 more
In order to understand the response of the Jovian magnetosphere to solar wind dynamic pressure enhancements, we investigate magnetic field variations observed by the Galileo spacecraft. The lack of solar wind monitoring just upstream of the Jovian magnetosphere is overcome by simulating a one-dimensional magnetohydrodynamic (MHD) propagation of th…
On the sources of fast and slow solar wind
Schwadron, N. A.; Landi, E.; Feldman, U.
The slow speed solar wind as measured at the Earth orbit and beyond is characterized by its velocity of ≃400 km s-1, by its coronal composition and by its frozen-in temperature (from carbon charge-states) of 1.4-1.6 × 106 K. In contrast the fast speed solar wind is characterized by its velocity of ≃750 km s-1, its …
Global structure of Jupiter's magnetospheric current sheet
Khurana, Krishan K.; Schwarzl, Hannes K.
Jupiter's magnetosphere contains a gigantic sheet-like structure located near its dipole magnetic equator that contains most of the plasma and energetic particles swirling in Jupiter's magnetosphere. Called the "current sheet," it behaves like a rigid structure inside a radial distance of ∼50 RJ where the periodic reversals of the B
Characteristics of the interplanetary coronal mass ejections in the heliosphere between 0.3 and 5.4 AU
Wang, C.; Richardson, J. D.; Du, D.
We identify and characterize interplanetary coronal mass ejections (ICMEs) observed by spacecraft in the solar wind, namely Helios 1 and 2, PVO, ACE, and Ulysses, which together cover heliocentric distances from 0.3 to 5.4 AU. The primary identification signature used to look for ICMEs is abnormally low proton temperatures. About 600 probable ICME…
Magnetohydrodynamic Simulations of the Solar Corona and Solar Wind Using a Boundary Treatment to Limit Solar Wind Mass Flux
Hayashi, Keiji
Magnetohydrodynamic simulations of the solar corona and solar wind are sensitive to conditions in the sub-Alfvénic plasma at the base of the solar corona because the structure of the simulated solar corona is determined by the pressure balance of the plasma and the magnetic field. Therefore, it is important to construct an adequate boundary treatm…