Extension of the ICRF for selected areas down to the 16th magnitude – II ^*,**,***

¹ Observatoire de Bordeaux, UMR 5804, CNRS/INSU, BP 89, 33270 Floirac, France
² Instituto de Astronomia, Geofísica e Ciências Atmosféricas da Universidade de São Paulo, Caixa Postal 3386, 01060-970 São Paulo SP, Brazil

Corresponding author: J. I. B. Camargo, camargo@obs.u-bordeaux1.fr

Received: 9 April 2003
Accepted: 4 June 2003

Abstract

In this paper we provide a major upgrade of the work presented in [CITE], aiming at the extension of the ICRF at optical wavelengths in regions of special astronomical interest, using observations from the Bordeaux and Valinhos meridian circles. Along with the new fields, the main differences, when compared to the first release, are: a much larger sky coverage, the replacement of the AC2000 by its upgraded version AC2000.2 as one of the first epoch astrometrical sources, inclusion of Tycho–2 and 2MASS photometry when available, and the correction for a magnitude equation on the Valinhos right ascension system as well. The resulting catalogue contains 678 828 entries with positional external precisions, on both coordinates, ranging from 50–60 mas () to 70–140 mas (). For the proper motions, precisions range from 3 mas/year to about 15 mas/year, depending on magnitude and declination.