Automated Spectroscopic abundances of A and F-type stars using echelle spectrographs

نویسندگان

  • D Erspamer
  • P North
چکیده

Using the method presented in Erspamer & North (2002, Paper I hereafter), detailed abundances of 140 stars are presented. The uncertainties characteristic of this method are presented and discussed. In particular, we show that for a S/N ratio higher than 200, the method is applicable to stars with a rotational velocity as high as 200 km s. There is no correlation between abundances and V sin i, except a spurious one for Sr, Sc and Na which we explain by the small number of lines of these elements combined with a locally biased continuum. Metallic giants (Hauck, 1986) show larger abundances than normal giants for at least 8 elements: Al, Ca, Ti, Cr, Mn, Fe, Ni and Ba. The anticorrelation for Na, Mg, Si, Ca, Fe and Ni with V sin i suggested by Varenne and Monier (1999) is not confirmed. The predictions of the Montréal models (e.g. Richard et al., 2001) are not fulfilled in general. However a correlation between [

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تاریخ انتشار 2002