The Pulkovo Programme of Photographic Observations of Spectroscopic Binary Stars as the Stars with Invisible Satellites

Abstract

The investigation of stars with invisible satellites on the basis of photographic observations with Pulkovo 26-inch refractor is one of the traditional problems in the Pulkovo observatory. Now 11 spectroscopic binary stars with known orbit are included in the program of photographic observations of stars with invisible satellites. Among them there is a control star ADS 15600 for which a speckle-interferometric orbit agreeing with spectroscopic orbit has been already obtained (McAlister, 1980). The aim of this program is to investigate the methods of determining a photocentric orbit for the star with a dark component comparing results with control stars. For other stars — to complete the spectral orbit, that is to determine inclination and longitude of ascending node. The observations are carried out since 1993. The first results of treatment for ADS 15600 don’t contradict to the control orbit. We obtain also that photocentre is placed closer to the less massive component.