Search Publications
Solar wind stream interfaces in corotating interaction regions: SWICS/Ulysses results
Wimmer-Schweingruber, Robert F.; von Steiger, Rudolf; Paerli, Raoul
Motivated by the well-known differences in charge state and even elemental composition of the slow solar wind as compared to high-speed streams, we have analyzed observations made by the Solar Wind Ion Composition Spectrometer (SWICS)/Ulysses mass spectrometer of the series of corotating interaction regions (CIRs) encountered by Ulysses in 1992/19…
A two-dimensional simulation of the radial and latitudinal evolution of a solar wind disturbance driven by a fast, high-pressure coronal mass ejection
Riley, Pete; Gosling, J. T.; Pizzo, V. J.
Using a hydrodynamic simulation, we have studied the two-dimensional (symmetry in the azimuthal direction) evolution of a fast, high-pressure coronal mass ejection (CME) ejected into a solar wind with latitudinal variations similar to those observed by Ulysses. Specifically, the latitudinal structure of the ambient solar wind in the meridional pla…
Direct observational evidence for a heliospheric magnetic field with large excursions in latitude
Schwadron, N. A.; Zurbuchen, T. H.; Fisk, L. A.
Fisk has pointed out that the heliospheric magnetic field in fast solar wind, that is, at the higher heliographic latitudes, may undergo large excursions in heliographic latitudes, and thus that the field will deviate from the expected Archimedes spiral pattern. These excursions result from the interplay between the nonradial expansion of the sola…
Magnetopause structure and the role of reconnection at the outer planets
Russell, C. T.; Szabo, A.; Le, G. +1 more
In situ measurements have been obtained at the magnetopause boundary of all the giant outer planets. The Jovian magnetopause was probed by Pioneers 10 and 11, Voyagers 1 and 2, Ulysses, and most recently by Galileo. Saturn was visited by Pioneer 11 and Voyagers 1 and 2, and Uranus and Neptune were visited by Voyager 2. The observations at Jupiter …
Coronal streamer belt asymmetries and seasonal solar wind variations deduced from Wind and Ulysses data
Steinberg, J. T.; Crooker, N. U.; Smith, E. J. +4 more
Solar wind measurements from Wind during March 1995 are combined with those from Ulysses' fast latitude scan to construct a map of the streamer belt. On the timescale of coronal change, the map is nearly a snapshot view of solar wind speed contours threaded by the trace of the heliospheric current sheet (HCS) in the +/-30° heliolatitude range. The…
Experimental constraints on pulsed and steady state models of the solar wind near the Sun
Habbal, S. R.; Wang, Y. -M.; Feldman, W. C. +1 more
Ulysses observations of the high-latitude solar wind were combined with Spartan 201 observations of the corona to investigate the nature and extent of uncertainties in our knowledge of solar wind structure near the Sun. In addition to uncertainties stemming from the propagation of errors in density profiles inferred from coronagraph observations […
A comparative study of cosmic ray radial and latitudinal gradients in the inner and outer heliosphere
Kunow, H.; Wibberenz, G.; Heber, B. +6 more
The radial and latitudinal intensity gradients of 145-255 MeV/nucleon He, 34-50 MeV/nucleon He and 30-69 MeV H are studied over an extensive range of heliocentric distances and latitudes for the 1993.0-1996.0 time period using data from cosmic ray experiments on the Ulysses, IMP 8, Voyager 1 and 2, and Pioneer 10 spacecraft. The radial gradients a…
Ulysses observations of wave activity at interplanetary shocks and implications for type II radio bursts
MacDowall, R. J.; Phillips, J. L.; Stone, R. G. +2 more
We present the first quantitative investigation of interplanetary type II radio emission in which in situ waves measured at interplanetary shocks are used to compute radio wave intensities for comparison with type II observations. This study is based on in situ measurements of 42 in-ecliptic forward shocks as well as 10 intervals of type II emissi…
Excess heating of 4He2+ and O6+ relative to H+ downstream of interplanetary shocks
Mall, Urs; Gloeckler, George; Geiss, Johannes +1 more
Using observations made by the solar wind ion composition spectrometer on Ulysses during its trip in the ecliptic plane to Jupiter, we examined the temperature ratios T(4He2+)/T(H+) and T(O6+)/T(H+) across 15 shocks, including forward and reverse shock pairs as well as isolated shocks. The mea…
Detection of Bernstein wave forbidden bands in the Jovian magnetosphere: A new way to measure the electron density
Forsyth, R. J.; Moncuquet, Michel; Meyer-Vernet, Nicole +2 more
We analyze the power spectra measured by the radio receiver of the Unified Radio and Plasma Wave experiment on Ulysses during its passage through the Jovian inner magnetosphere from ~9RJ in the outskirts of the Io plasma torus to ~13RJ near the plasma sheet. Below the plasma frequency fp, these spectra are weakly b…