SPADES: a stellar parameters determination software

¹ GEPI, Observatoire de Paris, CNRS, Université Paris Diderot, Place Jules Janssen, 92190 Meudon, France
e-mail: helene.posbic@obspm.fr
² Zentrum für Astronomie der Universität Heidelberg, Landessternwarte, Königstuhl 12, 69117 Heidelberg, Germany

Received: 14 April 2012
Accepted: 16 July 2012

Abstract

Context. As increasingly more spectroscopic data are being delivered by medium- and high-resolving power multi-object spectrographs, more automatic stellar parameter determination softwares are being developed. The quality of the spectra collected also allows the determination of elemental abundances.

Aims. SPADES is an automated software for determining: the radial velocity (V_r), the effective temperature (T_eff), the surface gravity (log g), the metallicity ( [Fe/H] ), and most importantly, the individual abundances. In this first version it is targeted on the analysis of mid-F-G dwarfs, but is meant to evolve to analyze any type of single stars.

Methods. SPADES relies on a line-by-line modeling to determine the stellar parameters.

Results. The internal systematic and random errors of SPADES were assessed by Monte Carlo method simulations with synthetic spectra and the external systematic errors by analysing real ground-based observed spectra. For example, by simulating the Giraffe setups HR13 and HR14B with synthetic spectra for a dwarf with  K, ,  dex and with a signal-to-noise ratio (S/N) of 100, the stellar parameters are recovered with no significant bias and with 1-σ precisions of 8 K for T_eff, 0.05 for log g, 0.009 for  [Fe/H] , 0.003 for  [Ti/Fe]  and 0.01 for  [Ni/Fe] .