Automatic abundance analysis of high resolution spectra

¹ Istituto Nazionale di Astrofisica – Osservatorio Astronomico di Trieste, via G. B. Tiepolo 11, 34131 Trieste, Italy
² Liceo Scientifico Statale Italiano Leonardo da Vinci, 12 rue Sedillot, 75007 Paris, France

Corresponding author: P. Bonifacio, bonifaci@ts.astro.it

Received: 18 September 2002
Accepted: 6 December 2002

Abstract

We describe an automatic procedure for determining abundances from high resolution spectra. Such procedures are becoming increasingly important as large amounts of data are delivered from 8 m telescopes and their high-multiplexing fiber facilities, such as FLAMES on ESO-VLT. The present procedure is specifically targeted for the analysis of spectra of giants in the Sgr dSph; however, the procedure may be, in principle, tailored to analyse stars of any type. Emphasis is placed on the algorithms and on the stability of the method; the external accuracy rests, ultimately, on the reliability of the theoretical models (model-atmospheres, synthetic spectra) used to interpret the data. Comparison of the results of the procedure with the results of a traditional analysis for 12 Sgr giants shows that abundances accurate at the level of 0.2 dex, comparable with that of traditional analysis of the same spectra, may be derived in a fast and efficient way. Such automatic procedures are not meant to replace the traditional abundance analysis, but as an aid to extract rapidly a good deal of the information contained in the spectra.