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Magnetic fields throughout the heliosphere
Smith, Edward J.
Measurements of the heliospheric magnetic field made over the last several years are surveyed with emphasis on Pioneer 11 observations near 35 AU and Ulysses observations between 1 and 5 AU. The increase in field magnitude at 1 AU near the recent sunspot maximum is also seen at Pioneer 11. Extrapolation of the magnitude and azimuthal component of …
Propagation of jovian electrons in and out of the ecliptic
Sierks, H.; Kunow, H.; Wibberenz, G. +5 more
Since its switch-on in Oct. 90, the Kiel Electron Telescope onboard Ulysses has detected many quiet time increases of the flux of 3-30 MeV electrons, known to originate from Jupiter. We report on the long term variations of this flux for the Ulysses ecliptic journey, and at the beginning of the out of ecliptic phase. They are well accounted for by…
Improved effective temperatures for hydrogen-deficient binary stars.
Jeffery, C. S.; Dudley, R. E.
Effective temperatures are obtained for all four known hydrogen-deficient binary stars, using published and archival photometry and new line-blanketed model atmospheres. These model atmospheres largely resolve the well-known mismatch between the theoretical and observed flux distribution for Upsilon Sgr, although a discrepancy persists at short wa…
Compton modelling of spectral variations observed in Z sources.
Wijers, R. A. M. J.; Schulz, N. S.
We present a simple model to fit the spectra of Z sources: a neutron star radiating at the centre of a hot scattering cloud. It is shown that the EXOSAT data of GX 17+2, GX 5-1, GX 340+0, and Sco X-2 (GX 349+2) in all branches of their Z profiles are represented well by this model. The neutron star temperature increases from the Horizontal Branch …
A Catalog of X-Ray Spectra of BL Lacertae Objects
Bassani, L.; Ciliegi, P.; Caroli, E.
This paper contains a list of X-ray spectra of BL Lac objects mostly collected from the literature. For a small sample of objects EXOSAT/ME spectra have also been analyzed and included in this list. In the catalog 42 objects are considered (26 radio selected and 16 X-ray selected) for a total of 311 X-ray spectra. For each object we report the X-r…
Ulysses observations of noncorotational flows in the outer dayside Jovian magnetosphere
Balogh, A.; Forsyth, R. J.; Cowley, S. W. H. +3 more
Using data from the Anisotropy Telescopes on the Ulysses spacecraft obtained during the February 1992 encounter with Jupiter, we have derived the bulk velocity of ions in the energy range 0.7-1.3 MeV which were detected in Jupiter's outer magnetosphere (at a jovicentric distance of between ∼80 and ∼110 RJ). The derived ion bulk velocity…
High-velocity tails on the velocity distribution of solar wind ions
Geiss, J.; Gloeckler, G.; Wilken, B. +2 more
Recent observations of the solar wind using the SWICS instrument on the Ulysses spacecraft have shown the presence of high-velocity ``tails'' on the velocity distribution of protons. Similar features have also been observed on the velocity distributions of helium and oxygen ions. Of the order of 1% of the solar wind density is involved in these ta…
Detection of [O ii] lambda 2471 from the Io Plasma Torus
Feldman, P. D.; Moos, H. W.; Strobel, D. F. +2 more
We report the first detection of the O II 2471-A forbidden line from the Io plasma torus. Observations of the east and west torus ansae at 5.7 R(J) on 1992 March 15 and May 1, respectively, using the Goddard High Resolution Spectrograph of the HST have resulted in about 5-sigma detections of the line on both occasions, with line brightnesses of 30…
Short Communication: Optical probing of dust in comet Grigg-Skjellerup from the Giotto spacecraft
Bertaux, J. L.; Levasseur-Regourd, A. C.; Renard, J. B. +3 more
The optical probe experiment (OPE) has provided the first in situ high-resolution optical probing of the very inner coma of a short period comet, during the 10 July 1992 encounter of the Giotto spacecraft with Grigg-Skjellerup. Preliminary results of the encounter are presented below. Indications of entering the dust coma occurred around 17,000 km…
The Spectrum of the Central Star of the Planetary Nebula in M22
Harrington, J. P.; Paltoglou, George
New optical observations of the central star of the planetary nebula IRAS 18333-2357 in the globular cluster M22 show lines of H I, He II, C IV, N IV, and N V. The spectrum closely resembles the sdO star KS 292, which has surface abundances enhanced by products of hydrogen shell burning and helium burning, and an effective temperature of 75,000 K.…