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A Solar Polar North-South Asymmetry for Cosmic-Ray Propagation in the Heliosphere: The ULYSSES Pole-to-Pole Rapid Transit
Simpson, J. A.; Bame, S.; Zhang, Ming
The pole-to-pole fast transit of the heliosphere at ~2 AU from the Sun by the international Ulysses spacecraft has made it possible for the first time to investigate in three dimensions the solar wind, interplanetary magnetic field, and---as reported herein---the global propagation of Galactic cosmic rays and anomalous helium. We use measurements …
The Elemental Composition of the Galactic Cosmic-Ray Source: ULYSSES High-Energy Telescope Results
Duvernois, M. A.; Thayer, M. R.
The nucleosynthetic origin of the galactic cosmic-ray sources (GCRS) is a matter of some considerable interest (e.g., Leske; Connell & Simpson; DuVernois et al.). Any understanding of this origin requires an accurate determination of the source elemental abundances. These abundances are determined by comparing the Ulysses High-Energy Telescope…
A Possible X-Ray Counterpart to SGR 1900+14
Hurley, K.; Kouveliotou, C.; Bowyer, S. +9 more
The location of the soft gamma repeater SGR 1900+14 was recently reduced to two ~5 arcmin2 alternate error boxes by the network synthesis method. We have used the ROSAT High Resolution Imager to observe the error box that is closest to the supernova remnant G42.8+0.6. A quiescent, steady, point X-ray source was found at alpha (2000) = 19h07m14.s15…
Detection of Low-Latitude Plumes in the Outer Corona by ULYSSES Radio Ranging Measurements
Woo, Richard
Low-latitude plumes have been detected beyond the field of view of coronagraphs in the range of 23--42 R0 in an equatorial coronal hole by Ulysses radio ranging measurements conducted in 1991 at 13 and 3.6 cm wavelengths. Exploiting the ranging measurement features of high sensitivity, wide dynamic range, high precision, high stability, and long d…
Possible Association of a Quiescent X-Ray Source with a Gamma-Ray Burster
Cline, T.; Hurley, K.; Kouveliotou, C. +10 more
We report on the first repeatedly detected statistically significant coincidence (chance probability ≈10-2-10-3) between an X-ray source and a gamma-ray burst error box. We present three ROSAT observations of the field of the gamma-ray burst of 1992 May 1. The first, a 2000 5 target of opportunity observation, was carried out…
Modulation of Anomalous Cosmic-Ray Ions by the Interplanetary Medium
Simnett, G. M.; Tappin, S. J.
Helioradius Dependence of Interplanetary Carbon and Oxygen Abundances during 1991 Solar Activity
Krimigis, S. M.; Lanzerotti, L. J.; Maclennan, C. G. +3 more
A comparison of the heliocentric dependence of the relative abundance of low energy (~1 MeV nucleon-1) carbon and oxygen on the Ulysses (~3--4 AU) and Voyager 1 and 2 (~35 and ~47 AU) spacecraft shows that the C/O abundance ratio is significantly smaller at the larger radial distances. This finding is attributed to a more abundant seed population …