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The historic plates of the "Carte du Ciel", an international cooperativeproject launched in 1887, offer valuable first-epoch material for thedetermination of absolute proper motions. We present the CdC-SF, an astrometriccatalogue of positions and proper motions derived from the "Carte du Ciel"plates of the San Fernando zone, photographic material with a mean epoch of1901.4 and a limiting magnitude of V~16, covering the declination range of-10deg < declination < -2deg. Digitization has been made using a conventionalflatbed scanner. Special techniques have been developed to handle thecombination of plate material and the large distortion introduced by thescanner. The equatorial coordinates are on the ICRS defined by Tycho-2, andproper motions are derived using UCAC2 as second-epoch positions. The result isa catalogue with positions and proper motions for 560000 stars, covering 1080degrees squared. The mean positional uncertainty is 0.20" (0.12" forwell-measured stars) and the proper-motion uncertainty is 2.0 mas/yr (1.2mas/yr for well-measured stars). The proper motion catalogue CdC-SF iseffectively a deeper extension of Hipparcos, in terms of proper motions, to amagnitude of 15.

Astrometry with "Carte du Ciel" plates, San Fernando zone. II. CdC-SF: a precise proper motion catalogue