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Magnetic Field Observations of Transient Events at Ulysses, 1996 2000
Balogh, A.; Forsyth, R. J.; Smith, E. J. +1 more
During the years 1996 2000 solar activity has been gradually rising and is now close to maximum. At the same time the Ulysses spacecraft has performed a north to south traverse of the low latitude regions of the heliosphere and is now once again travelling through high southerly latitudes. We show some examples and report on the occurence rates of…
Planar Structuring of Magnetic Fields at Solar Minimum and Maximum
Balogh, André; Jones, Geraint H.
Planar magnetic structures are regions of the solar wind where the magnetic field is oriented parallel to a fixed plane for several hours or more. Discontinuities in the field direction may be encountered during these periods, their surfaces also being parallel to the plane containing the field. A survey of Ulysses magnetic field data returned dur…
The Fall 2000 and Fall 2001 SOHO-Ulysses Quadratures
Suess, S.; Poletto, G.
SOHO-Ulysses quadrature occurs when their included angle with the Sun is 90°. At these times the same plasma leaving the Sun in the direction of Ulysses can first be remotely analyzed with SOHO and then later be sampled in situ at Ulysses. Quadratures in Fall 2000/2001 are of special interest because Ulysses will be near the south and north heliog…
Dust Properties in the Local Interstellar Medium
Kimura, Hiroshi; Mann, Ingrid
Ulysses measurements yield reliable in-situdetection of large dust particles which stem from the interstellar medium (ISM) and which are not observed in interstellar extinction data. Both current models of large grains in the ISM: core-mantle grains as well as composite grains, are in agreement with dust properties implied by the Ulysses results. …
Langmuir Wave Activity: Comparing the Ulysses Solar Minimum and Solar Maximum Orbits
McComas, D. J.; Lin, Naiguo; MacDowall, R. J.
We examine the occurrence and intensity of Langmuir wave activity (electrostatic waves at the electron plasma frequency) during the solar minimum and solar maximum orbits of Ulysses. At high latitudes during the solar minimum orbit, occurrences of Langmuir waves in magnetic holes were frequent; in the second orbit, they were less common. This diff…
In situ Wave Phenomena Associated with Magnetic Clouds and Other Ejecta
MacDowall, R. J.; Thejappa, G.
We present Ulysses Unified Radio and Plasma Wave (URAP) observations of ion-acoustic waves associated with magnetic clouds and ejecta. The peak intensities of these waves, which usually occur inside CMEs when T e/ T i≫1, are not correlated with heliocentric distance or electron to ion temperature ratio inside the CMEs.
Decay of Magnetic Field Irregularities Observed by Ulysses
Balogh, André; Erdos, Géza; Kóta, József
We study the solar cycle, radial, and latitudinal dependence of the characteristics of magnetic field irregularities in the Heliosphere. The frequency of magnetic field discontinuities is determined, using high time resolution magnetic field observations by Ulysses, covering the time interval from 1992 to 2000. The quasi-linear scattering mean fre…
Modulation Near Solar Maximum at High Solar Latitudes: Observations From the Ulysses Cospin High Energy Telescope
McKibben, R. B.; Zhang, M.; Lopate, C.
The three-dimensional structure of the solar maximum modulation of cosmic rays in the heliosphere can be studied for the first time by comparing observations from Ulysses at high solar latitudes to those from in-ecliptic spacecraft, such as IMP-8. Observations through mid-2000 show that changes in modulation remain well correlated at Earth and Uly…
Cosmic Ray Isotopic Composition Studies with the Ulysses High Energy Telescope: Implications for Origin and Distribution in the Galaxy
Simpson, J. A.; Connell, J. J.
The isotopic abundances of the Galactic cosmic radiation measured in the Heliosphere provide unique information on acceleration, propagation modes and containment times in the Galactic magnetic fields. Nuclear interactions with interstellar matter lead to observable γ-radiation production and, thus, to direct information on cosmic ray distribution…
Low Energy Particles in the Global Heliosphere 2001 2004: 1 to 90 AU
Krimigis, S. M.; Lanzerotti, L. J.; Armstrong, T. P. +4 more
Charged particle instrumentation that will be flying on six spacecraft in the heliosphere between 1 and 90 AU during 2001 2004 will provide a global view of the interplanetary medium that has not heretofore been available. Comparative analyses of the data that will be obtained will provide new understanding of the global evolution of heliospheric …