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A Radio-Optical Reference Frame.VIII.CCD Observations from KPNO and CTIO: Internal Calibration and First Results

Zacharias, N.; Winter, L.; de Vegt, C. +1 more

In this pilot investigation, precise optical positions in the FK5 system are presented for a set of 16 compact extragalactic radio sources, which will be part of the future radio-optical reference frame. The 0.9 m KPNO and CTIO telescopes equipped with 2 K CCDs have been used for this project. The astrometric properties of these instruments are in…

Field Distortions in the CPC2 Plate Data

Zacharias, N.

Residuals of a conventional plate adjustment of 5,687 plates of the Second Cape Photographic Catalogue (CPC2) using the Southern Reference Star (SRS) Catalog were analyzed to search for systematic errors depending on the location of the star images on the plate. Even after correcting for third order optical distortion, such coordinate depending sy…