2 Results

Table 1 lists 96 observations of 49 double stars performed at the Côte D'Azur observatory. The majority of them were made using magnifications of 750$\times$ and 938$\times$, the accuracy of the measurements is $2^\circ 0$ for position angles and 15% for angular separations.

Table 2 includes 216 measurements of 110 binaries made at Calar Alto observatory; for most, a Plössl 12 mm eyepiece with a magnification of 1016$\times$ was used. The imprecision estimated for $\theta$ is the same as in the previous case, whereas in $\rho$ it varies from 10% for close pairs to 5% for the very wide ones.

In both cases we also present, for a total of 58 double stars, the observed-calculated discrepancies of our measurements with respect to the last published orbit of the couple. Most of the orbits are included in the Fourth Catalog of Orbits of Visual Binary Stars (Worley & Heintz 1983) or in the Cinquième Catalogue d'Éphémérides d'Étoiles Doubles Visuelles (Couteau et al. 1986), in other cases the appropriate reference is given. The results are presented in the same format in both tables:

• Column 1: star's WDS catalogue number (WDS; Worley & Douglass 1997).
• Column 2: star's name (with letters denoting the components forming the binary).
• Column 3: ADS catalogue number if any (Aitken 1932).
• Column 4: epoch of observation, expressed in fractional Besselian year.
• Column 5: position angle.
• Column 6: angular separation.
• Column 7: number of nights (n) on which the star was observed.
• Column 8: identification code of the observer (LIN for Ling, PRI for Prieto).
• Columns 9 and 10: residuals in $\theta$ and $\rho$ with respect to the last known orbit of the pair.
• Column 11: the author and the year of publication orbit.

Acknowledgements

We sincerely thank Dr. P. Couteau for his generous help, and the Directorship and staff of the Fresnel Departament of the Côte D'Azur observatory, and Instituto Geográfico Nacional for the help and facilities made available at Nice and Calar Alto observatories respectively. This work was supported by the Spanish DGESIC under project PB97-0501.