Based on observations collected with FEROS at the European Southern Observatory at La Silla, Chile, ESO proposal No. 62. H-0319.

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Tables 1 and 2 are only available in electronic form at the CDS via anonymous ftp to cdsarc.u-strasbg.fr (130.79.128.5) or via http://cdsweb.u-strasbg.fr/cgi-bin/qcat?J/A+A/389/931

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Now at Royal Observatory Belgium, Ringlaan 2, Brussels.

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Research Director, Belgian Fund for Scientific Research (FWO).

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