CCD astrometry and components instrumental magnitude difference of 432 Hipparcos wide visual double stars ^*,**

¹ Institute of Astronomy and Astrophysics, National Observatory of Athens, I. Metaxa & Bas. Pavlou 15236, Greece e-mail: ds@astro.noa.gr
² National & Kapodistrian University of Athens, Dept. of Astronomy, Astrophysics and Mechanics e-mail: pgavras@astro.noa.gr
³ INAF – Osservatorio Astronomico di Roma, via de Frascati 33, Italy e-mail: dionatos@mporzio.astro.it
⁴ Observatory of the University of Bordeaux, France e-mail: ducourant@obs.u-bordeaux1.fr
⁵ University of Cape Town
⁶ South African Astronomical Observatory e-mail: thebe@saao.ac.za

Received: 23 August 2006
Accepted: 21 May 2007

Abstract

Context.We measured the angular separations, position angles, , and of wide visual double stars during the period 2003–2005. At least one component of the double stars in our sample has an entry in the Hipparcos catalogue.

Aims. Our measurements are a contribution to the study of the nature of these double stars.

Methods.The northern double stars of the project were observed with the 1.2 m telescope of the Kryonerion observatory and the southern with the 1.0 m SAAO. We performed multiple-exposure CCD imaging of our targets and used the standard procedure of data reduction and astrometric CCD calibrations.

Results.We present measurements of 213 northern and 219 southern wide binaries.