Cosmic ray and solar particle investigations over the South polar regions of the sun.

Observations of galactic cosmic radiation and anomalous component nuclei with charged particle sensors on the Ulysses spacecraft showed that heliospheric magnetic field structure over the south solar pole does not permit substantially more direct access to the local interstellar cosmic ray spectrum than is possible in the equatorial zone. Fluxes of galactic cosmic rays and the anomalous component increased as a result of latitude gradients by less than 50% from the equator to -80 degrees . Thus, the modulated cosmic ray nucleon, electron, and anomalous component fluxes are nearly spherically symmetric in the inner solar system. The cosmic rays and the anomalous nuclear component underwent a continuous, -26 day recurrent modulation to -80.2 degrees , whereas all recurring magnetic field compressions and recurring streams in the solar wind disappeared above approximately 55 degrees S latitude.

Energetic Charged-Particle Phenomena in the Jovian Magnetosphere: First Results from the Ulysses COSPIN Collaboration.

The Ulysses spacecraft made the first exploration of the region of Jupiter's magnetosphere at high Jovigraphic latitudes ( approximately 37 degrees south) on the dusk side and reached higher magnetic latitudes ( approximately 49 degrees north) on the day side than any previous mission to Jupiter. The cosmic and solar particle investigations (COSPIN) instrumentation achieved a remarkably well integrated set of observations of energetic charged particles in the energy ranges of approximately 1 to 170 megaelectron volts for electrons and 0.3 to 20 megaelectron volts for protons and heavier nuclei. The new findings include (i) an apparent polar cap region in the northern hemisphere in which energetic charged particles following Jovian magnetic field lines may have direct access to the interplanetary medium, (ii) high-energy electron bursts (rise times approximately 17 megaelectron volts) on the dusk side that are apparently associated with field-aligned currents and radio burst emissions, (iii) persistence of the global 10-hour relativistic electron "clock" phenomenon throughout Jupiter's magnetosphere, (iv) on the basis of charged-particle measurements, apparent dragging of magnetic field lines at large radii in the dusk sector toward the tail, and (v) consistent outflow of megaelectron volt electrons and large-scale departures from corotation for nucleons.