Search Publications
ULYSSES plasma parameters: latitudinal, radial, and temporal variations.
Goldstein, B. E.; Neugebauer, M.; Phillips, J. L. +6 more
Observations by the Ulysses SWOOPS plasma experiment are used to investigate spatial and temporal gradients during the mission, with emphasis on more recent high latitude observations including the recent South Pole to North Pole passage during solar minimum. Compared to lower latitudes, the high latitude solar wind had higher average speed, proto…
The heliospheric magnetic field at solar minimum: ULYSSES observations from pole to pole.
Balogh, A.; Horbury, T. S.; Forsyth, R. J. +3 more
The fast transit of the Ulysses spacecraft from the south polar regions of the heliosphere to the north polar regions has allowed us to obtain a unique perspective on the configuration and properties of the heliospheric magnetic field at a time of solar minimum activity. We compare the magnetic field in the northern and southern hemispheres and fi…
Spatial variation of >40MeV/n nuclei fluxes observed during the ULYSSES rapid latitude scan.
Kunow, H.; Wibberenz, G.; Potgieter, M. S. +7 more
In this paper we present fluxes of galactic cosmic ray nuclei with energies above 40MeV/n observed by the Kiel Electron Telescope on board the Ulysses spacecraft during the fast scan from the South Pole (September 1994) to the North Pole (July 1995). This part of the Ulysses orbit gives us the unique opportunity to investigate spatial modulation o…
Variation of electron-strahl width in the high-speed solar wind: ULYSSES observations.
McComas, D. J.; Forsyth, R. J.; Phillips, J. L. +2 more
Halo electron velocity distributions have been surveyed during the first full Ulysses southern polar pass from January 1994 through April 1995. The data examined range from approximately 50degS heliolatitude to the maximum poleward extent of the Ulysses orbit, approximately 80degS, and then back through the solar equator to 35degN heliolatitude. D…
The rate of turbulent evolution over the Sun's poles.
Balogh, A.; Horbury, T. S.; Forsyth, R. J. +1 more
Ulysses magnetic field observations in the polar heliosphere have revealed the presence of a population of turbulent fluctuations on small scales with a power spectral index near 5/3 and its extension to progressively larger scales with solar distance. Using the spectral index - calculated from the second order structure function - as a tracer of …
Constraints on high-speed solar wind structure near its coronal base: a ULYSSES perspective.
Phillips, J. L.; Wang, Y. -M.; Feldman, W. C. +1 more
Ulysses plasma data at high heliographic latitudes were studied to develop constraints on the structure of the corona at the base of the high-speed solar wind. Salient features of the flow poleward of +/-60° revealed: 1) low variances of all bulk flow parameters, 2) parameter values that agree with those measured during high-speed conditions in th…
Interstellar propagation of cosmic rays: analysis of the ULYSSES primary and secondary elemental abundances.
Duvernois, M. A.; Simpson, J. A.; Thayer, M. R.
The purpose of this investigation is to study the validity of the "leaky box" propagation model and determine some of its parameters. The pathlength distributions and their energy dependencies are derived from measurements of secondary-to-primary abundance ratios. A special charged particle telescope carried on the Ulysses spacecraft has provided …
Latitude variations of ~7MeV and >300MeV cosmic ray electron fluxes in the heliosphere: ULYSSES COSPIN/KET results and implications.
Sierks, H.; Kunow, H.; Wibberenz, G. +8 more
The 160° latitude scan performed in less than one year between summer 1994 and summer 1995 by Ulysses allowed us to obtain unique data about the latitudinal dependence of the cosmic ray fluxes. We present in this paper results on the electron component derived from the COSPIN/KET instrument onboard Ulysses, both at MeV and GeV energies. The variat…
Latitudinal dependence of the radial IMF component - interplanetary imprint.
Phillips, J.; Smith, E. J.; Goldstein, B. E. +2 more
Ulysses measurements have confirmed that there is no significant gradient with respect to heliomagnetic latitude in the radial component, B_r_, of the interplanetary magnetic field. There are two processes responsible for this observation. In the corona, the plasma β is <<1, except directly above streamers, so both longitudinal and latitudin…
Observations of galactic cosmic rays and the anomalous helium during ULYSSES passage from the south to the north solar pole.
Simpson, J. A.; McKibben, R. B.; Zhang, M. +2 more
We compare observations of the modulated intensities and spectra of galactic cosmic ray nuclei and anomalous helium above 30 MeV/n measured by the COsmic and Solar Particle INvestigations (COSPIN) High Energy Telescope (HET) on Ulysses with similar observations from the IMP-8 earth-orbiting satellite between September 1994 and August 1995. During …