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UV Spectra of the Eclipsing LMC X-Ray Binary CAL 87

Hutchings, J. B.; Crampton, D.; Cowley, A. P. +1 more

UV spectra of the supersoft x-ray binary CAL 87 have been obtained with the Faint Object Spectrograph of the HST. Eight spectra were obtained in 1995 January in a continuous observation covering the eclipse, from orbital phase 0.65 to 0.02. Interstellar extinction is modeled and removed to measure the system luminosity. The disk bolometric luminos…

The Ulysses south polar pass: Anomalous component of cosmic rays

Klecker, B.; Bothmer, V.; Sanderson, T. R. +4 more

We have expanded our previous study of latitudinal gradients of anomalous cosmic ray oxygen (8 to 12 MeV/n and 12 to 16 MeV/n) by using also helium (11 to 20 MeV/n) as an additional component and a larger ULYSSES/LET data set including the segment up to the maximum southern latitude and the pole-to-equator segment of the mission down to 38°S. The …

Dual-frequency radio sounding of the solar corona during the 1995 conjunction of the Ulysses spacecraft

Pätzold, M.; Bird, M. K.; Asmar, S. W. +2 more

The Ulysses Solar Corona Experiment was performed during the spacecraft's superior solar conjunction from 22 February to 14 March 1995, shortly before perihelion and the transit through the ecliptic plane. The high inclination of the Ulysses orbit resulted in an unusual occultation geometry for coronal radio sounding with the spacecraft's dual-fre…

HST observations of 3C305.

Sparks, W. B.; Macchetto, F.; Miley, G. K. +1 more

We present and discuss Hubble Space Telescope observations of the low-redshift radio galaxy 3C305 0.1" resolution images in [OII] and continuum bands are compared with VLA 2cm radio data. We quantify the radio-optical position offset in the northern lobe of the source and use this to constrain models of the interaction of radio jets with the ISM. …

Velocity Profile of the Ionized Disk and the Mass of the Black Hole in M87

Chakrabarti, Sandip K.

We present a theoretical model for the ionized disk in M87 which includes spiral shock waves. The line emission profiles computed from this model at various positions on the disk are found to be in agreement with the recent Hubble Space Telescope results. Based on this model, we find that the ionized disk comprises two-armed giant spiral shock wav…

Spectroscopic binary orbits from ultraviolet radial velocities. Paper 18: TU MUSCAE (HD 100213)

Stickland, D. J.; Lloyd, C.; Pachoulakis, I. +1 more

HST-GHRS observations of α Piscis Austrini. Evidence of no gas content in the circumstellar environment.

Deleuil, M.; Ferlet, R.; Vidal-Madjar, A. +4 more

The origin of the gaseous disk around the star β Pictoris is still unclear. A way to progress is to search for gas signatures in the environment of other stars presenting known IR excesses as initially discovered with the IRAS satellite. Recently, Cheng et al. (1994) reported the possible detection of circumstellar gas absorptions in the spectrum …

Anomalous gallium line profiles in HgMn stars: possible evidence for chemically stratified atmospheres.

Smith, Keith C.

An analysis of co-added high-resolution IUE spectra is presented for three mercury-manganese stars (µ Lep, HR 2844, and HR 7143) which exhibit anomalous Gaiii λ1495 resonance line profiles. This line appears to have unusually weak wings in these stars when compared with synthetic profiles computed under the conventional assumptions of atmosp…

A Search for r-Process Elements in the VELA Supernova Remnant

Jenkins, Edward B.; Wallerstein, George; Vanture, Andrew D. +1 more

After a description of recent developments in the physics of rapid neutron capture in Type II supernovae and a discussion of the detectability of supernovae ejecta, we present the data from a search for Ge, Kr, Yb, Os, and Hg in five stars behind or within the Vela remnant. Only Ge ii was detected, but its column density and the upper limits of th…

Cometary ion pickup processes: Halley and Grigg-Skjellerup compared

Johnstone, A. D.

After Giotto's encounters with two comets of quite different gas production rates we attempt to compare the results to see:- a) to what extent theories which fitted the results at Halley could be applied to the much smaller Grigg-Skjellerup; b) whether the different relationship between the various scale lengths involved created any observable eff…