Multicolour observations of nearby visual double stars. New CCD measurements and orbits*
Royal Observatory of Belgium, Av. Circulaire 3, 1180 Brussels, Belgium
2 Institute of Astronomy, Bulgarian Academy of Sciences, 72 Tsarigradsko Chausse Blvd., 1784 Sofia, Bulgaria e-mail: Anton.Strigachev@oma.be
Corresponding author: P. Lampens, Patricia.Lampens@oma.be
Accepted: 15 December 2000
We present multicolour CCD observations of nine nearby visual double stars obtained in August and September 1999 with the 1.3-m telescope at Skinakas Observatory. The results consist of relative positions (epochs, angular separations and position angles) and differential photometry. We confirm the physical association in eight cases. Previously known orbits do not match the new data for three systems. Orbits have been recalculated when sufficient data were available. We principally improve the precision of the known orbits for three binaries and show the acute lack of precision in two other cases. In one case, the components are shown to move apart with a linear relative speed of 0.050´´/yr.
Key words: stars: binaries: visual / stars: fundamental parameters / stars: nearby / techniques: photometric / astrometry
© ESO, 2001