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Element identifications in IUE spectra of chemically peculiar stars :the Pt-Au-Hg sequence.

Fuhrmann, K.

The presence of the elemental sequence Pt-Au-Hg in IUE spectra of chemically peculiar and normal stars is discussed. The sample comprises the HgMn (= CP3) stars HR4072, HR7775, and Chi Lup; the Ap (= CP2) stars HR465 and Alpha2 CVn; and the normal stars Vega (A0V) and Nu Cap (B9V). UV lines of Pt II, Au II and Hg II are identified on IUE spectra f…

Intermediate resolution spectra of quasars with z>2.

Ulrich, M. -H.

20 quasars (optically selected) with redshifts in the range 2-2.7 have been observed with a spectral resolution of 7 A, for a statistical study of the properties of the emission lines and also to find interesting candidates for detailed studies. The distribution of the observed equivalent width (EW) of C IV is centered at 95 A and the distribution…

Discovery of a BL Lacertae object (EXO 055625-3838.6) in the error box of H 0557-385.

Tagliaferri, G.; Beuermann, K.; Giommi, P. +3 more

We present X-ray and optical data of a new BL Lacertae type object (EXO 055625-3838.6) which has been serendipitously discovered in an EXOSAT CMA image and is located within the error box of HO557-385 (4U0557-38, 3A0557-383), a hard X-ray source previously identified with a seyfert 1 galaxy. Although the soft X-ray flux of the BL Lac is 1O times h…

The First UV Spectrum of Triton: IUE Observations from 2600 to 3200 Angstrom

Skinner, T. E.; Stern, S. Alan; Trafton, L. M. +2 more

The results of the first observations of Triton's spectrum below 3300 A are reported. Triton's 2700 A geometric albedo is found to be 0.28 + or - 0.04. The albedo increases monotonically from 2600 to 3200 A, with a slope of 0.13 + or - 0.03 per 1000 A. This positive slope is qualitatively similar to, but shallower than, Triton's visible albedo slo…

A photometric study of wide visual double stars with significant relative proper motion.

Sinachopoulos, D.

Photometric observations and uvby H-beta indices of 142 wide visual double stars are presented. Calibrations of the indices are used to derive MK class, color excess, absolute magnitude, effective temperature, and distance. The results are used to check candidates double stars for the Hipparcos mission for opticity.

Bl-Lacertae Objects as X-Ray Sources - the EXOSAT Observations

Maccagni, D.; Giommi, P.; Garilli, B. +2 more

Highly Ionized Species and Circumstellar Shells in B8--A1 Stars

Grady, C. A.; Bruhweiler, Frederick C.; Chiu, Weihsuen A.

The nature of the C IV and Si IV absorption seen in the spectra of apparently normal late-type B and early-type A stars located within 200 pc of the sun was investigated by examining a total of 93 archival IUE spectra of 41 stars. In three of these objects, variable or asymmetric C IV profiles indicate that the absorption features have a stellar o…

Properties of the components of the UZ Librae system.

Grewing, M.; Garrido, R.; Bianchi, L.

A reanalysis is conducted of the available photometric and spectroscopic data for the K-giant UZ Librae, including recent uvby photometry. The rotational period thus derived is close to, but not identical with the orbital period. Attention is given to UV spectra taken at different orbital/rotational phases. It is concluded that the overall propert…

The Ionization Structure of Planetary Nebulae. IX. NGC 1535

Barker, Timothy

The ionization structure of planetary nebula NGC 1535 was investigated using spectrophotometric observations of emission-line intensities over the spectral range 1400-7200 A, which were carried out in five positions in this nebula. The results obtained on the ionic abundances of He, O, N, Ne, C, and Ar in NGC 1535 suggest that it is a planetary ne…

The Chromosphere of Beta Cassiopeiae

Teays, Terry J.; Schmidt, Edward G.; Fracassini, Massimo +1 more

High-resolution, long-wavelength IUE observations and ground-based photometry of the Delta Scuti star Beta Cas is reported. The ground-based observations were used together with previous results of Antonello et al. (1986) to ensure that the IUE observations were correctly phased relative to the photometric variation. Fluxes for the emission core o…