Astrometry with Carte du Ciel plates, San Fernando zone*
II. CdC-SF: a precise proper motion catalogue
Instituto de Astrofísica de Canarias (IAC), 38200
La Laguna (S/C de Tenerife), Spain e-mail: email@example.com
2 Instituto de Astrofísica de Andalucía (IAA-CSIC), Apdo. 3004, 18080 Granada, Spain
3 Centro de Investigaciones de Astronomía (CIDA), Apdo. 264, Mérida, 3101-A Venezuela
4 Departamento de Astrofísica, Universidad de La Laguna, 38200 La Laguna (S/C de Tenerife), Spain
5 Department of Astronomy, Yale University, PO Box 208101, New Haven, CT 06520, USA
Accepted: 5 November 2009
Context. The historic plates of the Carte du Ciel, an international cooperative project launched in 1887, offer valuable first-epoch material for the determination of absolute proper motions.
Aims. We present the CdC-SF, an astrometric catalogue of positions and proper motions derived from the Carte du Ciel plates of the San Fernando zone, photographic material with a mean epoch of 1901.4 and a limiting magnitude of , covering the declination range of -10° ≤δ≤ -2°.
Methods. Digitization has been made using a conventional flatbed scanner. Special techniques have been developed to handle the combination of plate material and the large distortion introduced by the scanner. The equatorial coordinates are on the ICRS defined by Tycho-2, and proper motions are derived using UCAC2 as second-epoch positions.
Results. The result is a catalogue with positions and proper motions for 560 000 stars, covering 1080 degrees2. The mean positional uncertainty is 020 (012 for well-measured stars) and the proper-motion uncertainty is 2.0 mas/yr (1.2 mas/yr for well-measured stars).
Conclusions. The proper motion catalogue CdC-SF is effectively a deeper extension of Hipparcos, in terms of proper motions, to a magnitude of 15.
Key words: astrometry / catalogs / reference systems / surveys / stars: kinematics and dynamics
© ESO, 2010