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The Ulysses Cosmic Ray Isotope Experiment II: Source Abundances of Ne, Mg and Si Derived from High Resolution Measurements
Simpson, J.; Connell, J.
A Spectral Study of Four X-Ray--selected BL Lacertae Objects with EXOSAT
Maraschi, L.; Tagliaferri, G.; Treves, A. +2 more
We present new EXOSAT spectral results for four X-ray-selected BL Lac objects (H0323+022, H0414+009, H1426+428, and H1722+ 119). The data were retrieved from the EXOSAT data base. A spectral analysis was performed on the overall low-energy plus medium-energy distributions, which were modeled with a single, absorbed power law. In one case (H1426+42…
Rotational modulation and flares on the RS Canum Venaticorum binary II Pagasi in July/September 1990 : spots and flares on II Peg.
Doyle, J. G.; Mathioudakis, M.; Avgoloupis, S. +3 more
During ultraviolet spectroscopic observations of the RS CVn star II Peg in September 1990 a long duration (greater than or = 3 hrs.) flare was observed. During the early stage of the event, a feature at 1354 A was present, however, within the spectral resolution of the data it is not possible to identify this line. A contribution from the hot coro…
A Determination of the Basic Atmospheric Parameters of phi Cassiopeiae
Rosenzweig, Patricia; Anderson, Lawrence
By constructing non-LTE spherical model atmospheres, we have calculated a theoretical distribution of the emergent radiation that best matches the observed distribution of the supergiant Phi Cas, and so derived its effective temperature, surface gravity, and radius. Since Phi Cas is very likely a member of the open cluster NGC 457, we made extinct…
Ultraviolet and Optical Studies of Binaries with Luminous Cool Primaries and Hot Companions. IV. Further IUE Detections
Parsons, Sidney B.; Ake, Thomas B.
We have obtained IUE spectra for 31 middle and late-type giant and supergiant stars whose TD-1 fluxes or ground-based spectra indicate the presence of a hot component, or whose radial velocities indicate an unseen component. Stellar components earlier than type F1 were detected in 22 cases. While 20 of the hot secondaries are seen weakly in optica…
Detection of Far-Ultraviolet High-Excitation Line Emission and Lyman- beta Absorption in the Gravitational Lens Q0957+561
Kondo, Y.; Bruhweiler, F. C.; Michalitsianos, A. G. +7 more
Test runs with a new data processing software system on archival spectra obtained by the International Ultraviolet Explorer (IUE) reveal high-excitation emission lines in the gravitationally lensed binary quasar 0957+561. The lines of O VI λλ1031,1037 and S VI λ2933,945 are readily seen in a single 390 minute, low-dispersion IUE exposure, when cal…
Solar wind composition and expectations for high solar latitudes
Geiss, J.; von Steiger, R.
Instruments on board the Ulysses spacecraft are to investigate, for the first time, the solar wind in the three principal domains of solar latitude. (1) During Ulysses' flight in the ecliptic plane the solar wind near the current sheet was continuously measured, and its composition was determined with unprecedented sensitivity and mass resolution …
Spectroscopic binary orbits from ultraviolet radial velocities. Paper 13: HD 93205
Stickland, D. J.; Lloyd, C.
On the Chromosphere of 32 Cygni
Eaton, Joel A.
Archival IUE observations and new optical spectra of atmospheric eclipses are analyzed to define the physical properties of the chromosphere of 32 Cyg. Excitation temperatures clearly rise with height in the chromosphere, starting at about 5000 K close to the star. Temperatures in the range 12,000-17,000 K are attained high in the chromosphere, al…
Energetic particle, plasma and magnetic field signatures of a poloidal pulsation in Jupiter's magnetosphere
Dougherty, Michele K.; Balogh, André; Keppler, Erhard +6 more
During its February 1992 inbound journey into Jupiter's magnetosphere, Ulysses made several near-encounters with (and actual traversals of) the Jovian magnetodisk. In at least one such event (investigated here) the anticipated variations in energetic particle fluxes, plasma density, magnetic field intensity, and magnetic field direction at the pla…