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The narrow variable components of CIV in NGC 4151 from 1981 to 1987

Ulrich, M. -H.

The nucleus of the Seyfert 1 galaxy NGC 4151 undergoes large-amplitude variations and occasionally passes through deep minimum states lasting up to a few months. Two narrow emission lines, L_1 and L_2, variable in intensity on a time-scale of a few days were discovered during International Ultra-violet Explorer (IUE) campaigns at low states in 198…

ULYSSES observations of energetic particle acceleration and the superposed CME and CIR events of November 1992

Forsyth, R. J.; Keppler, E.; Kunow, H. +4 more

During November 1992, a series of forward and reverse shocks passed the ULYSSES spacecraft. Spectral and anisotropy measurements are reported for protons and alpha particles between 0.28 and 6 MeV observed by the Energetic Particle Composition Experiment, data recorded by the Magnetometer Experiment and the high-energy (2.7-300 MeV) proton data fr…

Simultaneous Multiwavelength Observations of Dwarf Novae. I. SU Ursae Majoris: Minihumps at a Minioutburst?

Vogt, N.; Szkody, P.; Roth, M. +19 more

SU Ursae Majoris the prototype of a subgroup of dwarf novae that display superhumps in super- outbursts has been observed during an international campaign dedicated to the observation of the first day of outburst of dwarf novae during 1986 February. After the start of a brightening was reported, the star was monitored by IUE, ground-based photomet…

Winds of Luminous OB Stars

Howarth, Ian D.; Prinja, Raman K.

We review the historical development of observations of mass loss from hot, luminous stars, and sketch the physical principles underlying the theory of radiatively-driven stellar winds. The theory makes predictions which are shown to be in general accord with the data. We summarize recent results, primarily from the IUE satellite, which demonstrat…

Faint Object Camera observations of complex nuclear structure in PKS 2158-380.

Boksenberg, A.; Blades, J. C.; Disney, M. J. +3 more

We present the results of Hubble Space Telescope observations of the nucleus of the narrow-line radio galaxy PKS 2158-380. Faint Object Camera images (taken before the December 1993 servicing mission) in bands centered near 3720A and 3420A show complex nuclear structure. The nucleus consists of three well resolved components of sizes ~0.3" (~0.28k…

A library of IUE white dwarf spectra for stellar population analyses.

Bonatto, C.; Bica, E.; Giovannini, O.

We present high Signal to Noise ratio IUE spectra of different classes of white dwarfs, to be used as templates for stellar population analyses in the ultraviolet region. We present average stellar parameters associated to each group. The library contains 6 groups for DA's, 2 for DO's and 5 for DB's. We also present equivalent widths of spectral f…

Symmetry in discontinuity properties at the north and south heliographic poles: Ulysses.

Balogh, A.; Tsurutani, B. T.; Goldstein, B. E. +3 more

A study of directional discontinuities (DDs) that occurred during 4 days of the Ulysses north polar pass was conducted (461 directional discontinuities total) using magnetic field and plasma data. We find that the total number of directional discontinuities selected by the Tsurutani and Smith (1979) method are the same in the north and south polar…

Spectroscopic binary orbits from ultraviolet radial velocities Paper 23: Pi Scorpii (HD 143018)

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

UV and X-Ray Monitoring of AG Draconis During the 1994/1995 Outbursts

Greiner, J.; Altamore, A.; González-Riestra, R. +3 more

The recent 1994-1995 active phase of AG Draconis has given us for the first time the opportunity to follow the full X-ray behaviour of a symbiotic star during two successive outbursts and to compare with its quiescence X-ray emission. With ROSAT observations we have discovered a remarkable decrease of the X-ray flux during both optical maxima, fol…

The galactic warp in young stars proper motions.

Lattanzi, M. G.; Smart, R. L.

Using Monte Carlo simulations of the Galaxy parameters, we have investigated the expected effects of a galactic warp model on the proper motions of early type stars. The introduction of the warp into the Galaxy simulation appears very pronounced in galactic latitude proper motions, but unobservable in galactic longitude proper motions. The proper …