Search Publications
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…
Energy deposition by Alfvén waves into the dayside auroral oval: Cluster and FAST observations
Balogh, A.; Dandouras, I.; Fazakerley, A. N. +16 more
We report in situ observations from the Cluster and FAST spacecraft showing the deposition of energy into the auroral ionosphere from broadband ULF waves in the cusp and low-latitude boundary layer. A comparison of the wave Poynting flux with particle energy and flux at both satellites indicates that energy transfer from the broadband waves to the…
Plasma sheet turbulence observed by Cluster II
Balogh, A.; Khurana, K. K.; Kistler, L. M. +8 more
Cluster fluxgate magnetometer (FGM) and ion spectrometer (CIS) data are employed to analyze magnetic field fluctuations within the plasma sheet during passages through the magnetotail region in the summers of 2001 and 2002 and, in particular, to look for characteristics of magnetohydrodynamic (MHD) turbulence. Power spectral indices determined fro…
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 …
Characteristic magnetic field and speed properties of interplanetary coronal mass ejections and their sheath regions
Owens, M. J.; Crooker, N. U.; Siscoe, G. L. +2 more
Prediction of the solar wind conditions in near-Earth space, arising from both quasi-steady and transient structures, is essential for space weather forecasting. To achieve forecast lead times of a day or more, such predictions must be made on the basis of remote solar observations. A number of empirical prediction schemes have been proposed to fo…
Contribution of nonadiabatic ions to the cross-tail current in an O+ dominated thin current sheet
Lundin, R.; Balogh, A.; Klecker, B. +8 more
During storm times, O+ can dominate both the pressure and the density in the plasma sheet. Because of the contribution from ion outflow, the plasma sheet is already oxygen-rich prior to substorm onset. At substorm onset the fraction of O+ contributing to the pressure and density increases. In the O+ dominated thin …
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
Solar wind control of the radial distance of the magnetic reconnection site in the magnetotail
Nakamura, R.; Fujimoto, M.; Baumjohann, W. +6 more
To understand magnetotail dynamics, it is essential to determine where magnetic reconnection takes place in the near-Earth magnetotail during substorms. The Geotail spacecraft thoroughly surveyed the near-Earth plasma sheet at radial distances of 10-31 RE during the years 1995-2003. Thirty-four clear reconnection events were identified …
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…
Acceleration and transport of heavy ions at coronal mass ejection-driven shocks
Li, Gang; Zank, G. P.; Rice, W. K. M.
It is now widely accepted that large solar energetic particle (SEP) events are associated with coronal mass ejection (CME)-driven shocks. Here, particles are often accelerated to approximately MeV energies (and perhaps up to GeV energies) at shock waves driven by CMEs. In this paper, on the basis of our earlier work, we present a detailed model wh…