Search Publications
The strongly constrained interacting binary BY Crucis.
Mayor, M.; Waelkens, C.; Daems, K.
We discuss spectroscopic and photometric observations (UV to IR) of BY Crucis, a new bright member of the interacting binaries of the W Serpentis class. The orbital period is 106.4days, and the mass function amounts to 5.92Msun_. The primary is an early-F supergiant which fills its Roche lobe; the massive secondary is hidden inside a th…
Ultraviolet observations of comet Hale-Bopp
Feldman, Paul D.
Ultraviolet spectroscopy and imaging of comet Hale-Bopp (C/1995 O1) were obtained from a variety of space platforms from shortly after the discovery of the comet through perihelion passage. Observations with the International Ultraviolet Explorer (IUE) and the Hubble Space Telescope (HST) spanned the range of 6.8 to 2.7 AU pre-perihelion, but IUE …
Ultraviolet DIB at 1369 A Arising in Molecular Clouds
Gnacinski, P.; Sikorski, J.; Kaczmarczyk, G.
Hubble Space Telescope (HST) and IUE observations of the weak unidentified interstellar line 1369 A in nine early type stars are discussed. This absorption feature might be a diffuse interstellar band (DIB). We have found good correlation between the equivalent widths of the 1369 A line and the interstellar CO A1Pi-X1Sigma (6…
Chromospherically Active Stars. XVI. The Double-Lined Binary 42 Capricorni
Fekel, Francis C.
New spectroscopic observations of the chromospherically active binary, 42 Capricorni, have resulted in the detection of lines of the secondary, improved orbital elements, and the determination of fundamental properties of the components. 42 Cap has an orbital period of 13.174004 d, an eccentricity of 0.176, and a mass ratio A/B of 1.375. No eviden…
Optical design of the coronal diagnostic spectrometer (an instrument on the Solar and Heliospheric Observatory)
Lidiard, Kate A.; Gray, Peter F.
The coronal diagnostic spectrometer (CDS) is one of 12 instruments that form the payload of the joint European Space Agency/National Aeronautics and Space Agency Solar and Heliospheric Observatory, launched in 1995. The CDS was designed and constructed by an international consortium led by the Rutherford Appleton Laboratory, United Kingdom. It is …
Discovery Of Mg-Rich Pyroxenes In Comet C/1995 O1 (Hale-Bopp): Pristine Grains Revealed At Perihelion
Woodward, Charles E.; Koike, Chiyoe; Wooden, Diane H. +2 more
The NASA Ames HIFOGS spectrometer observed comet C/1995 O1 (Hale-Bopp) at epochs including 96 Oct 7–14 UT (2.8 AU), 97 Feb 14–15 UT (1.2 AU), 97 Apr 11 UT (0.93 AU), and 97 Jun 22, 25 UT (1.7 AU). The HIFOGS 7.5–13.5 µm spectrophotometry (R = 360 - 180) of the silicate feature at 2.8 AU is identical in shape to the ISO SWS spectra of comet H…
Evidence for Absorption in NGC 1068
Boksenberg, A.; Catchpole, R. M.
We present evidence that interstellar absorption is responsible for producing much of the complex morphology seen in the inner few arcseconds of NGC 1068.
Absolute stellar proper motions with reference to galaxies of the M81 group
Meusinger, H.; Brosche, P.; Odenkirchen, M. +2 more
We report on the measurement of absolute proper motions of stars of magnitude 7 to 14.5 in a 2 deg X 2 deg field in the region of the M81 group of galaxies. This work is part of the Bonn program for the extragalactic link of Hipparcos. The proper motions were determined from a collection of photographic plates covering the time interval from 1894 …
HST WFPC2 Line and Continuum Images of NGC 1068
Ford, H. C.; Kriss, G. A.; Tsvetanov, Z. I. +1 more
Ultraviolet Ionization Stratification in Wolf-Rayet Winds
Rochowicz, Krzysztof
Ionization stratification can be used to study the structure of WR winds. In an accelerated outflow the stratification is observable through the Doppler effect as an inverse correlation of ionization potential (IP) with line width (FWHM). However, not only the average line widths of different ions, but also the line widths of one series of HeII sh…