GAUFRE: A tool for an automated determination of atmospheric parameters from spectroscopy

¹ Institute d'Astrophysique et de Géophysique, Université de Liège, 4000 Liège, Belgium
² School of Physics and Astronomy, University of Birmingham, UK
³ Argelander-Institut für Astronomie der Universität Bonn, Auf dem Hügel 71, 53121 Bonn, Germany
⁴ INAF-OAPd, Osservatorio Astronomico di Padova, Padova, Italy

^a e-mail: valentini@astro.ulg.ac.be

Abstract

We present an automated tool for measuring atmospheric parameters (T_eff, log g), [Fe/H]) for F-G-K dwarf and giant stars. The tool, called GAUFRE, is composed of several routines written in C++: GAUFRE-RV measures radial velocity from spectra via cross-correlation against a synthetic template, GAUFRE-EW measures atmospheric parameters through the classic line-by-line technique and GAUFRE-CHI2 performs a χ² fitting to a library of synthetic spectra. A set of F-G-K stars extensively studied in the literature were used as a benchmark for the program: their high signal-to-noise and high resolution spectra were analyzed by using GAUFRE and results were compared with those present in literature. The tool is also implemented in order to perform the spectral analysis after fixing the surface gravity (log g) to the accurate value provided by asteroseismology. A set of CoRoT stars, belonging to LRc01 and LRa01 fields was used for first testing the performances and the behavior of the program when using the seismic log g.