Astron. Astrophys. Suppl. Ser.
Volume 117, Number 2, June I 1996
|Page(s)||335 - 342|
|Published online||15 June 1996|
Optical positions of radio emitting stars *
Observatório Nacional/CNPq, Brazil
2 Observatório do Valongo/UFRJ, Brazil
3 Pulkovo Observatory, Russia
Corresponding author: Send offprint request to: M. Assafin, Observatório Nacional/CNPq, R. Gal. José Cristino 77, CEP20921-400, Rio de Janeiro, Brazil e-mail: email@example.com
Accepted: 20 November 1995
In order to contribute to the alignment of the radio and optical reference frames, 50 stars with confirmed radio emission and published radio positions were observed by astrographical means. Additionally, two confirmed radio-stars of fainter magnitude were observed using a CCD direct camera with a long focus, large aperture telescope. The reductions are made relative to four catalogues: the Carlsberg Meridian Catalogue #4, the International Reference Stars Catalogue, the Positions and Proper Motion Catalogue and the Astrographical Catalogue of Reference Stars. The best results were obtained with the CAMC catalogue. The plate error of a radio star position is 007 for both right ascension and declination, rising to 020 for bright stars. Ten of the program stars are not in the HIPPARCOS Input Catalogue and 12 do not belong to any of the major reference catalogues used. As soon as the HIPPARCOS results become available, its reference stars already measured in the plates will enable us to get positions for those 10 radio stars in the HIPPARCOS system.
Key words: astrometry / radio continuum: stars / reference systems
© European Southern Observatory (ESO), 1996