We present speckle observations of 48 double and multiple stars observed with the 2-meter ``Telescope Bernard Lyot'' (TBL) in December 1995, January 1997 and June 1997. Angular separations, absolute position angles and relative photometry result from these observations. New orbital elements have been recalculated for 8 double stars.
We present (table 1) the measurements of 167 visual double stars, made in 2000 and 2001 with the 50 cm refractor of the Nice Observatory and attached CCD camera, using an algorithm based on the adjustment of a tridimensional mathematical surface. Position angle, angular separation and magnitude difference are given. 33 new binaries (discovered by HIPPARCOS (HDS) or newly determined from Tycho-2 database (TDS)) discovered by Hipparcos were measured.
Recent CCD observations were performed in the period 1998-2004 for a large sample of visual double and multiple stars selected from the Hipparcos Catalogue (Cat. <I/239>) and/or from the Gliese Catalogue of Nearby Stars (Cat. <V/70>). Accurate astrometric and photometric data allowing us to characterise the individual components are provided. These data are compared to Hipparcos data or to data from an older epoch to assess the nature of the observed systems. We simultaneously apply a Moffat-Lorentz profile with a similar shape to all detected components and adjust the profile parameters from which we obtain the relative astrometric position (epoch, position angle, angular separation) as well as differential multi-colour photometry (filters (B)VRI).
The US Naval Observatory has mined over 140 astrometric catalogs, including the Astrographic Catalogue and the Two Micron All Sky Survey, for measures of double stars. This resulted in 114,218 new measures of 47,007 different systems spanning 110 years; these are now included in the Washington Double Star catalog (WDS). This is the single largest data set ever added to the WDS. The measures are typically of wider pairs, most between 4" and 30" thus, their value in aiding orbit determination is limited. However, they have proven invaluable in the verification of systems and the determination of rectilinear motions of systems.
We present the measurements of 49 visual double stars made in 1997 with the 50 cm refractor of the Nice Observatory (Table 1). A CCD camera was attached to this refractor. Some new binaries discovered by Hipparcos have been measured. The algorithm used for these measurements is based on the adjustment of a tridimensional mathematical surface.
We present the measurements of 65 visual double stars made in 1998 with the 50 cm refractor of the Nice Observatory (table 1). A CCD camera was attached to this refractor. 6 new binaries discovered by Hipparcos have been measured. The algorithm used for these measurements is based on the adjustment of a tridimensional mathematical surface.
Measures and discoveries of visual double stars made at the Observatoire de la Cote d'Azur at Nice, between 1988 and 1994, with the 50 cm refractor equipped with a filar micrometer and electronic recording device. The programs proposed by J. Dommanget involve the complement of the C.C.D.M. (resolving problems of identification of double stars and of coherency in the Index) and the INput CAtalog Hipparcos (resolution of ambiguities on the binarity and on the position of certain double stars which have seldom or never been observed again from the epoch or their discovery)
We present (table 1) the measurements of 58 visual double stars made in 1999 and 2000 with the 50 cm refractor of the Nice Observatory and attached CCD camera, using an algorithm based on the adjustment of a tridimensional mathematical surface. 2 new binaries discovered by Hipparcos (HDS) were measured.