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Acceleration of interstellar pickup ions in the disturbed solar wind observed on Ulysses
Geiss, J.; Lanzerotti, L. J.; Roelof, E. C. +6 more
Acceleration of interstellar pickup H+ and He+ as well as of solar wind protons and alpha particles has been observed on Ulysses during the passage of a corotating interaction region (CIR) at ~4.5 AU. Injection efficiencies for both the high thermal speed interstellar pickup ions (H+ and He+) and the low…
Ulysses field and plasma observations of magnetic holes in the solar wind and their relation to mirror-mode structures
Goldstein, Bruce E.; Neugebauer, Marcia; Smith, Edward J. +3 more
The term ``magnetic hole'' has been used to denote intervals when the magnitude of the interplanetary magnetic field drops to a few tenths, or less, of its ambient value for a time that corresponds to a linear dimension of tens to a few hundreds of proton gyro-radii. Data obtained by the Ulysses magnetometer and solar wind analyzer have been combi…
The whistler heat flux instability: Threshold conditions in the solar wind
Gary, S. Peter; Scime, Earl E.; Phillips, John L. +1 more
Solar wind electrons are observed often to consist of two components: a core and a halo. The anisotropies and relative average speed of these two components correspond to a heat flux that has the potential to excite several different electromagnetic instabilities; wave-particle scattering by the resulting enhanced fluctuations can limit this heat …
Regulation of the solar wind electron heat flux from 1 to 5 AU: Ulysses observations
Gary, S. Peter; Scime, Earl E.; Bame, Samuel J. +3 more
In this study we use observations from the three-dimensional electron spectrometer and magnetometer aboard the Ulysses spacecraft to examine the solar wind electron heat flux from 1.2 to 5.4 AU in the ecliptic plane. Throughout Ulysses' transit to 5.4 AU, the electron heat flux decreases more rapidly (~R-3.0) than simple collisionless e…
Ion injection and acceleration at quasi-perpendicular shocks
Giacalone, J.; Jokipii, J. R.; Kota, J.
We present and discuss results of a new model for ion injection and acceleration at quasi-perpendicular collisionless shocks. We use the one-dimensional hybrid simulation (kinetic ions/fluid electrons) and impose an assumption on the ion motion so that diffusion across the magnetic field (normal to the shock front) is possible. These motions are o…
Effects of spacecraft potential on three-dimensional electron measurements in the solar wind
Scime, Earl E.; Bame, Samuel J.; Phillips, John L.
Using the three-dimensional, low-energy electron spectrometer aboard the Ulysses spacecraft, we have measured the gyrotropicity of electron distributions in the solar wind. In order to make these observations, we have developed a new technique for correcting spacecraft charging effects in three-dimensional, low-energy particle measurements. Compar…
Ulysses near-ecliptic observations of differential flow between protons and alphas in the solar wind
Goldstein, B. E.; Bame, S. J.; Neugebauer, M. +1 more
The evolution of differential streaming between protons and alpha particles in the solar wind was observed with the solar wind plasma experiment on the Ulysses spacecraft over the solar range of 1.15 to 5.40 AU between November 18, 1990, and May 5, 1992. The correlation of the difference in ion speeds, ΔV=||Vα||-||Vp||, with …
An analysis of whistler waves at interplanetary shocks
Forsyth, R.; Balogh, A.; Farrell, W. M. +2 more
We present an analysis of whistler wave magnetic and electric field amplitude ratios from which we compute wave propagation angles and energies of electrons in resonance with the waves. To do this analysis, we compute the theoretical dependence of ratios of wave components on the whistler wave propagation angle Theta for various combinations of or…
Asymmetries in the Io plasma torus
Kaiser, M. L.; Desch, M. D.; Farrell, W. M.
Using Ulysses radio wave data taken during the 1992 Jupiter encounter, we conclude that there are significant large and small spatial scale azimuthal asymmetries at high latitudes in the Io plasma torus. During a period of time near perijove when the spacecraft motion was predominantly in the azimuthal direction and was relatively fixed in both la…
Whistler mode waves in the Jovian magnetosheath
Tsurutani, B. T.; Lin, Naiguo; Kellogg, P. J. +3 more
During the Ulysses flyby of Jupiter in February 1992, the spacecraft transversed the Jovian magnetosheath for a few hours during the inbound pass and for a few days during the outbound pass. Burstlike electromagnetic waves at frequencies of ~0.1-0.4 of the local electron cyclotron frequency have been observed by the Unified Radio and Plasma Wave (…