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The ULYSSES Cosmic Ray and Solar Particle Investigation

Balogh, A.; Sierks, H.; Kunow, H. +28 more

The Ulysses experimental program termed Cosmic Ray and Solar Particle Investigation (COSPIN) is described, with special attention given to the scientific objectives of the COSPIN, the measurements performed, the initial postlaunch results, and the characteristics of the individual COSPIN instruments. The instrument package of the COSPIN experiment…

The ULYSSES Mission

Smith, E. J.; Marsden, R. G.; Page, D. E. +1 more

The Unified Radio and Plasma wave investigation

de Conchy, Y.; Goetz, K.; Desch, M. D. +7 more

The scientific objectives of the Ulysses Unified Radio and Plasma wave (URAP) experiment are twofold: (1) the determination of the direction, angular size, and polarization of radio sources for remote sensing of the heliosphere and the Jovian magnetosphere and (2) the detailed study of local wave phenomena, which determine the transport coefficien…

NGC 1705. I. Stellar Populations and Mass Loss Via A Galactic Wind

Freeman, K. C.; Meurer, Gerhardt R.; Dopita, Michael A. +1 more

We present a detailed multi-waveband study of the galaxy NGC 1705. The data include optical and ultraviolet spectroscopy, optical and infrared photoelectric aperture photometry, narrowband and broadband images, H I spectra, and data from the IRAS point source catalog. NGC 1705 is shown to be a nearby (D~5 Mpc for H_0_ = 75 km s^-1^ Mpc^-1^) nuclea…

Reconstruction of the accretion disk in six cataclysmic variable stars.

Rutten, R. G. M.; van Paradijs, J.; Tinbergen, J.

The maximum-entropy eclipse-mapping algorithm is used to reconstruct images of the accretion disks of the novalike variable stars RW Tri, UX UMa, SW Sex, LX Ser, V 1315 Aql, and V363 Aur. The 2D disk intensity maps deduced from the light curves reveal the size of the disk and its radial intensity dependence. Black-body temperature maps deduced fro…

Correlated Hard X-Ray and Ultraviolet Variability in NGC 5548

Nandra, K.; Clavel, J.; Reichert, G. A. +7 more

We present the result of a series of contemporaneous (within one day) hard X-ray (Ginga) and ultraviolet (IUE) observations of the Seyfert 1 galaxy NGC 5548. Nine of these observations were carried out over a period of 51 days in 1990 May-July, and two in 1989. An additional simultaneous IUE-EXOSAT observation obtained on 1984 May 21 is also analy…

The Abundance of Boron in Three Halo Stars

Lambert, David L.; Lemke, Michael; Duncan, Douglas K.

B abundances for three halo stars: HD 140283, HD 19445, and HD 201891 are presented. Using recent determinations of the Be abundance in HD 140283, B/Be of 10 +5/-4 is found for this star, and similar ratios are inferred for HD 19445 and HD 201891. This ratio is equal to the minimum value of 10 expected from a synthesis of B and Be by high-energy c…

Ultraviolet Observations of the Gas Phase Abundances in the Diffuse Clouds toward zeta Ophiuchi at 3.5 Kilometers per Second Resolution

Savage, Blair D.; Sofia, Ulysses J.; Cardelli, Jason A.

Goddard High Resolution Spectrograph echelle mode measurements at 3.5 km/s resolution are presented for interstellar absorption produced by C II, O I, Mg I, Mg II, Al III, P II, Cr II, Mn II, Fe II, Ni II, Cu II, Zn II, Ga II, Ge II, and Kr I. The absorption line measurements are converted into representations of apparent column density per unit v…

Heliosphere Instrument for Spectra, Composition and Anisotropy at Low Energies

Simnett, G. M.; Pick, M.; Anderson, K. A. +7 more

The Heliosphere Instrument for Spectra, Composition, and Anisotropy at Low Energies (HI-SCALE) is designed to make measurements of interplanetary ions and electrons throughout the entire Ulysses mission. The ions (E(i) greater than about 50 keV) and electrons (E(e) greater than about 30 keV) are identified uniquely and detected by five separate so…

X-Ray--heated Models of Stellar Flare Atmospheres: Theory and Comparison with Observations

Hawley, Suzanne L.; Fisher, George H.

A sequence of five model atmospheres consisting of the photosphere, chromosphere, and transition region is computed. The models represent the response of the gas in a magnetically confined loop to intense flare energy release. It is concluded that the structure of the flare transition region is consistent with the conductive heating balancing opti…