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Li I 6708 in normal A and F-type stars.
Castelli, F.; Gerbaldi, M.; Faraggiana, R.
The 6708 A Li region has been observed in a sample of unevolved stars of spectral type A-early F and the Li abundances have been determined by using the synthetic spectrum method. As the intensity of the Li I 6708 doublet decreases rapidly with increasing T_eff_ in these stars, we have to pay special attention to the list of lines present in the v…
Astrometry of 19 globular clusters.
Johnston, H. M.; Picard, A.
We present accurate positions for the center of 19 globular clusters, 8 of which are known to contain X-ray sources and/or pulsars. The positions are based on a new centroiding algorithm applied to CCD images of the clusters. The fundamental astrometry is performed with plates from the ESO Schmidt telescope, using the Hipparcos Input Catalogue as …
The UV properties of normal galaxies. II. The ``non-IUE'' data.
Longo, G.; Capaccioli, M.; Rifatto, A.
In the last decade several satellite and balloon borne experiments have collected a large number of ultraviolet fluxes of normal galaxies measured through apertures of various sizes and shapes. We have homogenized this data set by deriving scale corrections with respect to IUE. In a forthcoming paper these data will be used to derive standard lumi…
The ultraviolet spectrum of η Carinae. II. 1980 IUE observations of the Homunculus.
Baratta, G. B.; Viotti, R.; Cassatella, A.
We analyze the ultraviolet observations of the circumstellar nebula of η Car (the Homunculus) obtained in December 1980 with IUE. A high resolution spectrum was obtained with the IUE large aperture from 6" to 17" NW of η Car, near the H condensation (the head). The measured flux appears two orders of magnitude larger than that expected from the in…
CCD astrometry and instrumental {DELTA}V photometry of wide visual double stars. IV. Differential measurements of northern pairs.
Sinachopoulos, D.; van Dessel, E.; Nakos, T.
We present relative positions and instrumental visual magnitude differences ({DELTA}V) of 101 northern wide double star components. The mean accuracy of the magnitude differences is 0.01 magnitudes, of the angular separation 0.04 arcseconds, and of position angle 0.13 degrees. Most of the programme pairs are targets of the HIPPARCOS mission and th…
Photographic observations of visual double stars.
Jasinta, D. M. D.; Raharto, M.; Soegiartini, E.
We present the results of photographic observations of 399 visual double stars of the Hipparcos Input Catalogue (HIC), observed in the years 1980 and 1990-1991 with the 60-cm double-refractor of the Bosscha Observatory at Lembang, Java.
VRI photometry of wide double stars with A- type primaries.
Cuypers, J.; Lampens, P.; Sinachopoulos, D. +2 more
We are presenting VRI photometry of 93 wide visual double stars having late B- or A- type primaries, taken from the Annex of Double and Multiple Stars of the HIPPARCOS Input Catalogue. Spectral types have been estimated for most of the primaries and for the majority of the secondaries. 40% of them probably have common origin components, for which …