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Description
All reliable observations of point sources with the ultraviolet photometer onboard the Astronomical Netherlands Satellite (ANS) operating between the October 1974 and April 1976 are presented. Extended objects, non-detected objects, and objects at the edges of the instrument's field of view have been omitted. The catalog contains 3573 objects, mostly stars (the total ANS UV database contained 4800 observed positions). The ANS satellite observed in five UV channels centered around 150, 180, 220, 250 and 330 nm (1500, 1800, 2200, 2500 and 3300 Angstroms). The characteristics of the ANS UV photometric bands are: <pre> Band designation 15N 15W 18 22 25 33 ------------------------------------------------------------------------- Central wavelength (nm) 154.5 154.9 179.9 220.0 249.3 329.4 Bandwidth (nm) 5.0 14.9 14.9 20.0 15.0 10.1 </pre> The reported magnitudes were obtained from mean count rates converted to fluxes using the ANS absolute calibration of Wesselius et al. (1980A&A....85..221W). In addition to the ultraviolet magnitudes, the catalog contains positions taken from the satellite pointing, spectral types, and UBV data from other sources as well as comments on duplicity, variability, and miscellaneous notes concerning individual objects. Within the ANS photometric system, the UV magnitudes of different objects are comparable down to a level of 0.5-1.0%. Several studies on the intercomparison of all ANS data, and on the comparison of the ANS data with stellar models, with other UV satellites, and with the expected UV fluxes on the basis of ground-based information alone suggest that the ANS photometric system is well-established, and has, in particular, a linear dynamic range of at least a factor of 20,000. In these two respects, repeatability and dynamic range, the ANS UV instrument far exceeded all other UV missions then extant, e.g., TD-S2/68, OAO-WEP, and IUE. Of course, ANS had a much poorer spectral resolution, about 15 nm (150 Angstroms), than the other instruments. This table was created by the HEASARC in September 2011 based on <a href="https://cdsarc.cds.unistra.fr/ftp/cats/II/97">CDS Catalog II/97</a> file ans.dat. This is a service provided by NASA HEASARC .
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