Search Publications
Coronal Mass Ejections at High Heliographic Latitudes: ULYSSES
Balogh, A.; McComas, D. J.; Bame, S. J. +3 more
Nine coronal mass ejections (CMEs) have been detected in the solar wind by the Ulysses plasma experiment between 31° and 61° South. One of these events, which was also a magnetic cloud, was directly associated with an event observed by the soft X-ray telescope on Yohkoh in which large magnetic loops formed in the solar corona directly beneath Ulys…
Interplanetary discontinuities and Alfvén waves
Tsurutani, Bruce T.; Goldstein, Bruce E.; Neugebauer, Marcia +6 more
The rate of occurrence of interplanetary discontinuities (ROID) is examined using Ulysses magnetic field and plasma data from 1 to 5 AU radial distance from the Sun and at high heliospheric latitudes. It is found that there are two regions in interplanetary space where the ROID is high: in stream-stream interaction regions and in Alfvén wave train…
Radial and Meridional Trends in Solar Wind Thermal Electron Temperature and Anisotropy: ULYSSES
Forsyth, R. J.; Bame, S. J.; Scime, E. E. +3 more
Ulysses plasma measurement from 1.15 to 5.31 AU and from S6.4° to S48.3° solar latitude are used to assess the trends in the solar wind thermal electron temperature and anisotropy. Improved spacecraft potential corrections and data products have been incorporated. The radial temperature gradient is steeper than in previous determinations, but flat…
Proton phase space densities (0.5eV<Ep<5MeV) at midlatitudes from Ulysses SWICS/HI-SCALE measurements
Roelof, E. C.; Gloeckler, G.; Ogilvie, K. W. +1 more
Proton phase space densities in the solar wind frame from suprathermal velocities 10 km s-1 to 30,000 km s-1 (0.5 eV 5 MeV) were derived from combined SWICS and HISCALE measurements when Ulysses was at 5 AU and -24° heliolatitude. The period (19 23 January 1993) encompasses a forward/reverse shock pair (20 January, 0500 UT an…
The Elemental Composition in Energetic Particle Events at High Heliospheric Latitudes
Krupp, N.; Fränz, M.; Keppler, E. +2 more
The relative abundances of low energy ions (0.6 2.0 MeV/n) in solar energetic particle (SEP) and corotating interaction region (CIR) events have been measured by the EPAC experiment aboard Ulysses since launch in October 1990 until the present time. We give an overview of the abundances of heavy ions (He, C, Ne, Fe) relative to oxygen during energ…
High-Latitude Observations of Energetic Ions During the First ULYSSES Polar Pass
Balogh, A.; Forsyth, R. J.; Goldstein, B. E. +3 more
We present observations of energetic ions from the Ulysses COSPIN Low Energy Telescope in the mid and high-latitude regions of the heliosphere prior to and during the first polar pass of the Ulysses spacecraft. After the encounter with Jupiter, Ulysses started on its journey out-of-the-ecliptic. Between ∼13°S and ∼29°S the spacecraft sampled the s…
Solar Wind Charge States Measured by Ulysses/SWICS in the South Polar Hole
Galvin, A. B.; Cohen, C. M. S.; Ipavich, F. M. +2 more
The Ulysses mission now has an extensive data base covering several passes of the south polar coronal hole as the spacecraft proceeds to higher latitudes. Using composition measurements from the SWICS experiment on the Ulysses spacecraft, we have obtained charge state distributions, and hence inferred coronal ionization temperatures, for several s…
Alfvenic Fluctuations in the Solar Wind: A Case Study Using ULYSSES Measurements
Balogh, A.; Forsyth, R. J.; Scime, E. E. +3 more
We present preliminary results of a study of solar wind Alfvénic fluctuations using magnetometer and plasma measurements from the spacecraft Ulysses. We focus on a particular case study, and use ‘wave language’ to discuss the fluctuations. The observations are consistent with a mixture of convected structures and Alfvén wave trains. Furthermore, o…
Energetic Particles at High Latitudes
Wibberenz, G.; Müller-Mellin, R.
We review work on diffusion coefficients of energetic particles with an attempt to extract implications on their behaviour at high latitudes. In the ecliptic plane results from solar energetic particle propagation between the Sun and about 5 AU can be described by an effective radial mean free path λ r which is approximately constant a…
IMF Connection for Energetic Protons Observed at ULYSSES via Mid-Latitude Solar Wind Rarefaction Regions
Simnett, G. M.; Armstrong, T. P.; Roelof, E. C.
As Ulysses moved inward and southward from mid-1992 to early 1994 we noticed the occasional occurrence of “inter-events”, lasting about 10 days and falling between the recurrent events, observed at proton energies of 0.48 97 MeV, associated with Corotating Interaction Regions (CIR). These inter-events were present for several sequences of two or m…