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Latitudinal and radial variation of >2 GeV/n protons and alpha particles in the southern heliosphere at solar maximum: Ulysses cospinket and neutron monitor network observations
Kunow, H.; Wibberenz, G.; Heber, B. +7 more
Ulysses, launched in October 1990, began in its second out-of-ecliptic orbit in September 1997 and its second fast latitude scan in November 2000. In contrast to the first orbit with the Sun declining to low activity, we are now at solar maximum conditions. The Kiel Electron Telescope (KET) on-board Ulysses measures proton and alpha-particles in t…
The cosmic ray radial and latitudinal gradients in the heliosphere near solar minima
Zhang, M.; McDonald, F. B.
Based on existing measurements of galactic and anomalous cosmic ray gradients obtained by the heliopsheric network spacecraft in the last three solar minima, we found that there is an approximately linear relationship between the magnitudes of the radial gradient and latitudinal gradient. Cosmic rays of a particular species/energy that exhibit a l…
The Ulysses Fast Latitude Scan at Solar Maximum: COSPIN/LET energetic particle observations
Forsyth, R. J.; Sanderson, T. R.; Marsden, R. G. +3 more
Having completed the second survey of the southern polar regions of the heliosphere in late 2000, the Ulysses spacecraft is presently engaged in its second so-called Fast Latitude Scan (FSL). During this phase of the out-of-ecliptic orbit, the spacecraft makes a rapid transit from south to north, covering 160° in solar latitude in less than 320 da…
Time-dependent 3-D modelling of the heliospheric propagation of few-MeV electrons
Fichtner, H.; Ferreira, S. E. S.; Potgieter, M. S. +2 more
With a recently developed steady-state model of the propagation of Jovian and galactic electrons in the inner three-dimensional heliosphere we were able to demonstrate both the necessity and value of such modelling for (i) the determination of the diffusion tensor of energetic particles, (ii) an observational discrimination between Jovian and inte…
Intensities of galactic cosmic ray nuclei from the ecliptic to the south solar polar regions near solar maximum: observations from the ULYSSES COSPIN high energy telescope
Heber, B.; McKibben, R. B.; Zhang, M. +2 more
Ulysses reached its maximum south heliographic latitude of 80.2° S in late November 2000, near the maximum in the solar activity cycle and is now embarked on a fast latitude scan that will bring it to a perihelion at 1.34 AU near the solar equator by mid-May 2001. Throughout the period of increasing solar activity since Ulysses left the ecliptic i…
Ulysses High Energy Telescope Measurements of the Isotopic Abundances of Galactic Cosmic Rays for Elements between C and Fe with Estimates of the Source Composition
Connell, J. J.
We report new and revised high resolution measurements of the isotopic composition of Galactic cosmic rays in the Solar system using data from the High Energy Telescope (HET) on the Ulysses Spacecraft. These data have significantly improved statistics compared with our earlier measurements. Mass resolution varies from ~0.08 to ~0.31 u at observed …
Latitudinal transport of 7 MeV Jovian and galactic electrons in the inner heliosphere
Fichtner, H.; Ferreira, S. E. S.; Potgieter, M. S. +2 more
The heliospheric modulation of galactic and Jovian electrons is studied using a fully three-dimensional, steady-state model based on Parker's transport equation including the Jovian source. The model is used to study the latitudinal transport of both 7 MeV Jovian and galactic electrons by illustrating how the electron intensities are affected at d…
Coherence of Charged Particle Oscillations in the Heliosphere (f∼5 µHz): Implications for a Solar Modulation Source
Kunow, H.; Lanzerotti, L. J.; Maclennan, C. G. +3 more
Time series analysis of low energy electron and high energy proton cosmic ray fluxes, both measured on the Ulysses spacecraft, shows that they are coherent in some frequency bands in the energy range 0-6 µHz, especially near 5 µHz. Interplanetary particle fluxes with very different kinematic properties (e.g., gyrofrequencies) are modulated coheren…
Solar cycle variations of GCR anisotropies at Ulysses
Fraenz, M.; Heber, B.; Blake, J. B. +1 more
The four telescope array of the EPAC investigation aboard Ulysses provides a good measurement of the anisotropy of the > 230 MeV GCR ux during those frequent time periods when MeV solar electrons are not present. We focused on the time period since late 1994 and found that the angular distribution of the GCR, as determined by the ratio of count…
Cosmic Ray Elemental Source Composition: Observations with the Ulysses High Energy Telescope
Connell, J. J.; Burin de Roziers, E.
We will present new and revised measurements of cosmic ray source abundances from boron to nickel. The High Energy Telescope (HET) on the Ulysses spacecraft provides high resolution measurements of cosmic rays, separating elements from hydrogen to nickel for energies ranging from 40 to 400 MeV/u. We determine cosmic ray source abundances by compar…