Search Publications
Spectral line identification of the ultraviolet spectrum of the peculiar post-AGB star HD 101584 (F0Iape)
Bakker, E. J.
The high resolution (R~10^4^) near-ultraviolet IUE spectrum of the peculiar post Asymptotic Giant Branch (post-AGB) supergiant HD 101584 (F0Iape) has been analyzed. In the wavelength range between 2500 and 3000 A , 291 out of 332 absorption features are identified. The main contribution comes from FeII, CrII and MnII. Most of the absorption featur…
Measurements of the sky background using the HST Faint Object Camera.
Hook, R. N.; Fosbury, R. A. E.; Caulet, A.
The results of a novel method of measuring the three dominant components of the sky brightness from the Hubble Space Telescope orbit are reported. The shadows cast by an occulting finger in the Faint Object Camera (FOC), when the field is dispersed with an objective prism, are separated into three features: the geocoronal Lyα and neutral oxygen ai…
Optical polarization of 1000 stars within 50 PC from the Sun
Leroy, J. L.
We have prepared a catalogue of optical polarization measurements for 1000 stars closer than 50 parsecs from the Sun. The distances, which are presently those given in the Sky Catalogue 2000.0, 2nd edition (Hirshfeld et al. 1991) are provisional: they will be replaced later by the much safer parallaxes which will result from the Hipparcos mission.…
Determination of field distortion by a plate-overlap method.
Abad, C.
An automated reduction method for determining field distortion common to all plates based on a black-adjustment method proposed by Stock (1981) is demonstrated on the Paris Zone of the Astrographic Catalog. It is shown that the FK5 is suitable as the only reference source for zone catalogs.
Anomalous proper motions in the Cygnus superbubble region.
Jordi, C.; Torra, J.; Comeron, F. +1 more
In an analysis of proper motions of O and B stars contained in the Input Catalogue for Hipparcos, we have found a clear deviation from the expected pattern of systematic motions which can be readily identified with the associations Cygnus OB1 and Cygnus OB9, located near the edge of the Cygnus Superbubble. The anomalous motions are directed outwar…
ULYSSES precise localizations of gamma-ray bursts.
Cline, T.; Hurley, K.; Kouveliotou, C. +10 more
The Ulysses mission is presently about 5 AU from Earth, in the vicinity of Jupiter. It carries a gamma-ray burst detector sensitive to ≈ 15 - 150 keV X-rays, with time resolution down to 8 ms. for the purpose of high accuracy burst localization by the time-of-arrival method. This spacecraft, which is farther from Earth than any previous mission wi…
CCD astrometry and instrumental (Delta)V photometry of wide visual double stars. III. Differential measurements of often observed southern pairs.
Sinachopoulos, D.; van Dessel, E.
We present accurate relative positions and instrumental visual (Bessel V) magnitude differences of southern wide star components. The mean accuracy of the angular separation is 0.02 arcsecs, which corresponds to 1.5 micron on the CCD chip, and of magnitude difference 0.007 mag/exposure. The program pairs are targets of the HIPPARCOS mission and th…
CPC2: The Second Cape Photographic Catalogue. I - History, observations and plate measurements
Zacharias, N.; Murray, C. A.; de Vegt, C. +3 more
The Second Cape Photographic Catalog is discussed. The observations and measurements involved in the preparation of the first version of the catalog are described. The present stellar reference frame is reviewed, and the observational program, reduction process, and plate measurement for the catalog are examined.
Ultraviolet spectroscopy of nova MUSCAE 1991.
Panagia, N.; Horne, K.; Shrader, C. R. +4 more
We report on a series of ultraviolet spectroscopic observations made with the IUE satellite, which sampled critical outburst stages of the soft X-ray transient Nova Muscae 1991. Continuum light curves, and a multi-epoch line analysis are presented. In addition, a single epoch optical-UV spectra obtained with the HST/FOS is discussed. The optical-U…
Ephemerides of the 48 HIPPARCOS minor planets for the year 1993
Bec-Borsenberger, A.
To be observed by Hipparcos, the position of each object has to be known with an accuracy of 1 arcsecond and its magnitude with an accuracy of 0.5 mag. Therefore, the orbital elements of the 48 selected minor planets of the Hipparcos mission, have been improved in order to extrapolate their ephemerides with the accuracy required. Updated ephemerid…