1085 I/85 Cape Photographic Catalogue 2 W Nicholson M J Penston C A Murray C de Vegt Mon. Not. Roy. Astron. Soc. 208 911 1984 1984MNRAS.208..911N Positional data Proper motions Photographic catalog This catalog contains the provisional positions for 51018 stars in the Cape zone -40 deg. to -52 deg., on the FK4 system for the equinox 1950.0. The internal mean error of a single coordinate obtained from the mean of r=four plates is estimated to be less than +/- 0.1" at the mean epoch of observation, about 1962. The systematic deviation from the FK4 system in a small area is probably also about +/-0.1". New proper motions have been determined for 22731 stars which are also in the Smithsonian Astrophysical Observatory (SAO) catalogue; the formal mean error of an annual proper motion in each coordinate is about +/-0.004"/a.

The usable width of each plate is 4.1 deg. Stars were selected from the SRS and SAO catalogs, with the SRS providing the reference frame. All SAO stars were included except in crowded fields near the galactic plane, in which many SAO stars were omitted. Stars were then added by visual inspection to bring the number up to about 250, with as uniform a distribution as possible over the plate. The number of stars measured per plate varied from 70 to more than 700. The numbering system adopted is based on the South Polar Distance of a band of declination 1 deg. wide with the stars within each band being numbered sequentially in the order of right ascension. Approximate visual magnitudes have been determined from the image diameters calibrated by the V values from the published literature. Only three plates have fewer than 10 such standards; 75% of the plates have between 15 and 30. Generally, the available stars are brighter than V-9.5 mag.

ID CPC2P number --- SAO SAO number --- SRS SRS number --- RAs Right ascension seconds (1950) s DE- Sign of declination --- DEs Declination seconds (1950) arcsec mag Magnitude cmag ep Epoch of observation - 1900 a e_RAs Internal mean error in RAs arcsec e_DEs Internal mean error in DEs arcsec n_mag Magnitude status 0 = not available 1 = normal 2 = variable --- o_pos Number of plates used for position --- o_mag Number of plates used for magnitude --- del_SS Separation of SRS and CPC2 positions arcsec pmRA Annual proper motion in RA s-4/a pmDE Annual proper motion in declination marcsec/a e_pmRA Mean error of proper motion in RA s-4/a e_pmDE Mean error of pm in declination marcsec/a del_pm Larger pm diff. |CPC2-SAO| in RA or DE marcsec/a N. G. Roman ADC/SSDOO 1997Jul25 I_85.xml