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Mesoscale structure of a morning sector ionospheric shear flow region determined by conjugate Cluster II and MIRACLE ground-based observations
Janhunen, P.; Lester, M.; André, M. +10 more
We analyse a conjunction event of the Cluster II spacecraft with the MIRACLE ground-based instrument net-work in northern Fennoscandia on 6 February 2001, between 23:00 and 00:00 UT. Shortly after the spacecraft were located at perigee, the Cluster II satellites’ magnetic footpoints move northwards over Scandinavia and Svalbard, almost perfectly a…
The Ulysses fast latitude scans: COSPIN/KET results
Kunow, H.; Wibberenz, G.; Posner, A. +6 more
Ulysses, launched in October 1990, began its second out-of-ecliptic orbit in December 1997, and its second fast latitude scan in September 2000. In contrast to the first fast latitude scan in 1994/1995, during the second fast latitude scan solar activity was close to maximum. The solar magnetic field reversed its polarity around July 2000. While t…
Observation of energy-time dispersed ion structures in the magnetosheath by CLUSTER: possible signatures of transient acceleration processes at shock
Budnik, E.; Balogh, A.; Dandouras, I. +11 more
We analyse energy-time dispersed ion signatures that have been observed by CLUSTER in the dayside magnetosheath. These events are characterized by sudden increases in the ion flux at energies larger than 10 keV. The high energy ions (30 keV) are first detected, with the transition to the low energy ions (5 keV) lasting about 100 s. These injection…
Solar cycle variations of the energetic H/He intensity ratio at high heliolatitudes and in the ecliptic plane
Lario, D.; Roelof, E. C.; Maclennan, C. G. +3 more
We study the variability of the heliospheric energetic proton-to-helium abundance ratios during different phases of the solar cycle. We use energetic particle, solar wind, and magnetic field data from the Ulysses, ACE and IMP-8 spacecraft to compare the H/He intensity ratio at high heliographic latitudes and in the ecliptic plane. During the first…
From the Sun's south to the north pole - Ulysses COSPIN/LET composition measurements at solar maximum
Sanderson, T. R.; Marsden, R. G.; Tranquille, C. +1 more
Based on elemental abundance ratios derived from the Ulysses COSPIN/LET measurements, we classified the energetic particle populations during and after the socalled Fast Latitude Scan - the time period during which the Ulysses spacecraft traveled from the highest heliolatitude south to maximum northern latitude, i.e. 27 November 2000 to 13 October…
Latitudinal extent of large-scale structures in the solar wind
McComas, D. J.; Riley, P.; Elliott, H. A.
Comparison of solar wind observations from the ACE spacecraft, in the ecliptic plane at ~ 1 AU, and the Ulysses spacecraft as it orbits over the Sun's poles, provides valuable information about the latitudinal extent and variation of solar wind structures in the heliosphere. While qualitative comparisons can be made using average properties observ…
On the heliolatitudinal variation of the galactic cosmic-ray intensity. Comparison with Ulysses measurements
Moussas, X.; Exarhos, G.
We study the dependence of cosmic rays with heliolatitude using a simple method and compare the results with the actual data from Ulysses and IMP spacecraft. We reproduce the galactic cosmic-ray heliographic latitudinal intensity variations, applying a semi-empirical, 2-D diffusion-convection model for the cosmic-ray transport in the interplanetar…
A survey of 3He enhancements at 2-20 MeV/nucleon: Ulysses COSPIN/LET observations
Sanderson, T. R.; Marsden, R. G.; Tranquille, C. +1 more
We present the results of a survey of enhancements in the ratio of 3He/4 He as measured by the COSPIN/LET instrument on board the Ulysses spacecraft in the energy range 2-20 MeV/n. In the context of this study, all ratios of 3He/4 He above 0.05 are considered to be enhanced compared with the solar system value of ~0.0004. Previous studies have sho…